— USGS (@USGS) July 17, 2014
From The Denver Post (Nancy Lofholm):
Trash trucks are once again picking up the garbage on West Salt Creek Road near Collbran — one of the best signs, residents say, that some sense of normalcy is returning to those living under the threat of more movement from a giant mudslide.
“We feel very comfortable now. We feel like there is so much intelligence coming in now and that they are really watching that mountain,” said Celia Eklund, who lives along lower West Salt Creek Road.
The residents there are still on alert from the Mesa County Sheriff’s Office since the mountain above them slid on May 25 and buried three local men who had gone up to check on a smaller slide that occurred earlier that day…
Dozens of experts from local, state and federal agencies have studied the slide that is now being called a “debris avalanche” or a “rapid earthflow” by geologists. They have used high-tech aerial imaging, GPS and water flow meters and have installed monitors that can detect even slight movements in the slide.
They now have a more accurate size on the slide, which is smaller than originally estimated.
The latest information from the U.S. Geological Survey shows that the slide stretches for 2.5 miles and covers 550 acres…
The slide contains a pool of water at the top behind a large block of earth that broke off from the Grand Mesa where the slide originated. Geologists now estimate that pool will hold about 245 acre feet of water before it could reach an outlet and spill over. A gauge has been installed by the USGS Colorado Water Science Center just below the toe of the landslide to measure any flow from the slide.
Heather Benjamin with the Mesa County Sheriff’s Office said the Army Corps of Engineers joined the geologists from the USGS and the Colorado Geological Survey this week. The entire group of geologists and emergency management personnel from the Colorado Department of Public Safety have been holding nightly briefings since the slide occurred.
USGS: Dissolved-Solids Sources, Loads, Yields, and Concentrations in Streams of the Conterminous United StatesJune 27, 2014
Here’s the abstract from the United States Geological Survey (David W. Anning and Marilyn E. Flynn):
Recent studies have shown that excessive dissolved-solids concentrations in water can have adverse effects on the environment and on agricultural, domestic, municipal, and industrial water users. Such effects motivated the U.S. Geological Survey’s National Water Quality Assessment Program to develop a SPAtially-Referenced Regression on Watershed Attributes (SPARROW) model that has improved the understanding of sources, loads, yields, and concentrations of dissolved solids in streams of the conterminous United States.
Using the SPARROW model, long-term mean annual dissolved-solids loads from 2,560 water-quality monitoring stations were statistically related to several spatial datasets that are surrogates for dissolved-solids sources and land-to-water delivery processes. Specifically, sources in the model included variables representing geologic materials, road deicers, urban lands, cultivated lands, and pasture lands. Transport of dissolved solids from these sources was modulated by land-to-water delivery variables that represent precipitation, streamflow, soil, vegetation, terrain, population, irrigation, and artificial drainage characteristics. Where appropriate, the load estimates, source variables, and transport variables were statistically adjusted to represent conditions for the base year 2000. The nonlinear least-squares estimated SPARROW model was used to predict long-term mean annual conditions for dissolved-solids sources, loads, yields, and concentrations in a digital hydrologic network representing nearly 66,000 stream reaches and their corresponding incremental catchments that drain the Nation.
Nationwide, the predominant source of dissolved solids yielded from incremental catchments and delivered to local streams is geologic materials in 89 percent of the catchments, road deicers in 5 percent of the catchments, pasture lands in 3 percent of the catchments, urban lands in 2 percent of the catchments, and cultivated lands in 1 percent of the catchments. Whereas incremental catchments with dissolved solids that originated predominantly from geologic sources or from urban lands are found across much of the Nation, incremental catchments with dissolved solids yields that originated predominantly from road deicers are largely found in the Northeast, and incremental catchments with dissolved solids that originated predominantly from cultivated or pasture lands are largely found in the West. The total amount of dissolved solids delivered to the Nation’s streams is 271.9 million metric tons (Mt) annually, of which 194.2 million Mt (71.4%) come from geologic sources, 37.7 million Mt (13.9%) come from road deicers, 18.2 million Mt (6.7%) come from pasture lands, 13.9 million Mt (5.1%) come from urban lands, and 7.9 million Mt (2.9%) come from cultivated lands.
Nationwide, the median incremental-catchment yield delivered to local streams is 26 metric tons per year per square kilometer [(Mt/yr)/km2]. Ten percent of the incremental catchments yield less than 4 (Mt/yr)/km2, and 10 percent yield more than 90 (Mt/yr)/km2. Incremental-catchment yields greater than 50 (Mt/yr)/km2 mostly occur along the northern part of the West Coast and in a crescent shaped band south of the Great Lakes. For example, the median incremental-catchment yield is 81 (Mt/yr)/km2 for the Great Lakes, 78 (Mt/yr)/km2 for the Ohio, and 74 (Mt/yr)/km2 for the Upper Mississippi water-resources regions. Incremental-catchment yields less than 10 (Mt/yr)/km2 mostly occur in a wide band across the arid lowland of the interior West that excludes areas along the coast and the extensive, higher mountain ranges. For example, the median incremental-catchment yield is 3 (Mt/yr)/km2 for the Lower Colorado, 5 (Mt/yr)/km2 for the Rio Grande, and 8 (Mt/yr)/km2 for the Great Basin water-resources regions.
Predicted incremental loads were cascaded down through the reach network, with loads accumulating from reach to reach. For most stream reaches, the entire incremental load of dissolved solids delivered to the reach was transported to either the ocean or to one of the large streams flowing along the U.S. international boundary without losses occurring along the way. The exceptions to this include streams in the southwestern part of the country, such as the Colorado River, Rio Grande, and streams of internally drained drainages in the Great Basin, where dissolved-solids loads decreased through streamflow diversion for off-stream use, or by infiltration through the streambed.
Long-term mean annual flow-weighted concentrations were derived from the predicted accumulated-load and stream-discharge data. Widespread low concentrations, generally less than 100 milligrams per liter (mg/L), occur in many reaches of the New England, South Atlantic-Gulf, and Pacific Northwest water-resources regions as a result of moderate dissolved-solids yields and high runoff rates. Widespread moderate concentrations, generally between 100 and 500 mg/L, occur in many reaches of the Great Lakes, Ohio, and Upper Mississippi River water-resources regions. Whereas dissolved-solids yields are generally high in these regions, runoff rates are also high, which helps moderate concentrations in these regions. Widespread higher concentrations, generally greater than 500 mg/L, occur across a belt of reaches that extends almost continuously from Canada to Mexico in the Midwest, cutting through the Souris-Red-Rainy, Missouri, Arkansas-White-Red, Texas-Gulf, and Rio Grande water-resources regions. Although dissolved-solids yields are moderate to low in these areas, low runoff rates result in the high concentrations for these areas.
In 12.6 percent of the Nation’s stream reaches, predicted concentrations of dissolved solids exceed 500 mg/L, the U.S. Environmental Protection Agency’s secondary, nonenforceable drinking water standard. While this standard provides a metric for evaluating predicted concentrations in the context of drinking-water supplies, it should be noted that it only applies to drinking water actually served to customers by water utilities, and it does not apply to all stream reaches in the Nation nor does it apply during times when water is not being withdrawn for use. Exceedance of 500 mg/L is more pronounced in certain water-resources regions than others. For example, about half of the reaches in the Souris-Red-Rainy region have concentrations predicted to exceed 500 mg/L, and between 25 and 37 percent of the reaches in the Missouri, Arkansas-White-Red, Texas-Gulf, Rio Grande, and Lower Colorado regions are predicted to exceed 500 mg/L.
Development of stream-load data for use in the SPARROW model also provided long-term temporal trend information in dissolved-solids concentrations at the monitoring stations for their period of record, which was constrained between 1980 and 2009. For the 2,560 monitoring stations used in this study, long-term trends in flow-adjusted dissolved-solids concentrations increased over time at 23 percent of the stations, decreased at 18 percent of the stations, and did not change over time at 59 percent of the stations. Long-term trends show a strong regional spatial pattern where from the western parts of the Great Plains to the West Coast, concentrations mostly either did not change or decreased over time, and from the eastern parts of the Great Plains to the East Coast, concentrations mostly either did not change or increased over time.
Results from the trend analysis and from the SPARROW model indicate that, compared to monitoring stations with no trends or decreasing trends, stations with increasing trends are associated with a smaller percentage of the predicted dissolved-solids load originating from geologic sources, and a larger percentage originating from urban lands and road deicers. Conversely, compared to stations with increasing trends or no trends, stations with decreasing trends have a larger percentage of the predicted dissolved-solids load originating from geologic sources and a smaller percentage originating from urban lands and road deicers. Stations with decreasing trends also have larger percentages of predicted dissolved-solids load originating from cultivated lands and pasture lands, compared to stations with increasing trends or no trends.
More water pollution coverage here.
Click here to go to the Water Watch website for Colorado from the United States Geological Survey.
USGS: Mercury in Fishes from 21 National Parks in the Western United States—Inter- and Intra-Park Variation in Concentrations and Ecological RiskApril 23, 2014
Mercury (Hg) is a global contaminant and human activities have increased atmospheric Hg concentrations 3- to 5-fold during the past 150 years. This increased release into the atmosphere has resulted in elevated loadings to aquatic habitats where biogeochemical processes promote the microbial conversion of inorganic Hg to methylmercury, the bioavailable form of Hg. The physicochemical properties of Hg and its complex environmental cycle have resulted in some of the most remote and protected areas of the world becoming contaminated with Hg concentrations that threaten ecosystem and human health. The national park network in the United States is comprised of some of the most pristine and sensitive wilderness in North America. There is concern that via global distribution, Hg contamination could threaten the ecological integrity of aquatic communities in the parks and the wildlife that depends on them. In this study, we examined Hg concentrations in non-migratory freshwater fish in 86 sites across 21 national parks in the Western United States. We report Hg concentrations of more than 1,400 fish collected in waters extending over a 4,000 kilometer distance, from Alaska to the arid Southwest. Across all parks, sites, and species, fish total Hg (THg) concentrations ranged from 9.9 to 1,109 nanograms per gram wet weight (ng/g ww) with a mean of 77.7 ng/g ww. We found substantial variation in fish THg concentrations among and within parks, suggesting that patterns of Hg risk are driven by processes occurring at a combination of scales. Additionally, variation (up to 20-fold) in site-specific fish THg concentrations within individual parks suggests that more intensive sampling in some parks will be required to effectively characterize Hg contamination in western national parks.
Across all fish sampled, only 5 percent had THg concentrations exceeding a benchmark (200 ng/g ww) associated with toxic responses within the fish themselves. However, Hg concentrations in 35 percent of fish sampled were above a benchmark for risk to highly sensitive avian consumers (90 ng/g ww), and THg concentrations in 68 percent of fish sampled were above exposure levels recommended by the Great Lakes Advisory Group (50 ng/g ww) for unlimited consumption by humans. Of the fish assessed for risk to human consumers (that is, species that are large enough to be consumed by recreational or subsistence anglers), only one individual fish from Yosemite National Park had a muscle Hg concentration exceeding the benchmark (950 ng/g ww) at which no human consumption is advised. Zion, Capital Reef, Wrangell-St. Elias, and Lake Clark National Parks all contained sites in which most fish exceeded benchmarks for the protection of human and wildlife health. This finding is particularly concerning in Zion and Capitol Reef National Parks because the fish from these parks were speckled dace, a small, invertebrate-feeding species, yet their Hg concentrations were as high or higher than those in the largest, long-lived predatory species, such as lake trout. Future targeted research and monitoring across park habitats would help identify patterns of Hg distribution across the landscape and facilitate management decisions aimed at reducing the ecological risk posed by Hg contamination in sensitive ecosystems protected by the National Park Service.
More water pollution coverage here.
USGS: Geologic Sources and Concentrations of Selenium in the West-Central Denver Basin, Including the Toll Gate Creek Watershed, Aurora, Colorado, 2003–2007April 21, 2014
Here’s the abstract from the USGS (Suzanne S. Paschke/Katherine Walton-Day/Jennifer A. Beck/Ank Webber/Jean A. Dupree)
Toll Gate Creek, in the west-central part of the Denver Basin, is a perennial stream in which concentrations of dissolved selenium have consistently exceeded the Colorado aquatic-life standard of 4.6 micrograms per liter. Recent studies of selenium in Toll Gate Creek identified the Denver lignite zone of the non-marine Cretaceous to Tertiary-aged (Paleocene) Denver Formation underlying the watershed as the geologic source of dissolved selenium to shallow ground-water and surface water. Previous work led to this study by the U.S. Geological Survey, in cooperation with the City of Aurora Utilities Department, which investigated geologic sources of selenium and selenium concentrations in the watershed. This report documents the occurrence of selenium-bearing rocks and groundwater within the Cretaceous- to Tertiary-aged Denver Formation in the west-central part of the Denver Basin, including the Toll Gate Creek watershed. The report presents background information on geochemical processes controlling selenium concentrations in the aquatic environment and possible geologic sources of selenium; the hydrogeologic setting of the watershed; selenium results from groundwater-sampling programs; and chemical analyses of solids samples as evidence that weathering of the Denver Formation is a geologic source of selenium to groundwater and surface water in the west-central part of the Denver Basin, including Toll Gate Creek.
Analyses of water samples collected from 61 water-table wells in 2003 and from 19 water-table wells in 2007 indicate dissolved selenium concentrations in groundwater in the west-central Denver Basin frequently exceeded the Colorado aquatic-life standard and in some locations exceeded the primary drinking-water standard of 50 micrograms per liter. The greatest selenium concentrations were associated with oxidized groundwater samples from wells completed in bedrock materials. Selenium analysis of geologic core samples indicates that total selenium concentrations were greatest in samples containing indications of reducing conditions and organic matter (dark gray to black claystones and lignite horizons).
The Toll Gate Creek watershed is situated in a unique hydrogeologic setting in the west-central part of the Denver Basin such that weathering of Cretaceous- to Tertiary-aged, non-marine, selenium-bearing rocks releases selenium to groundwater and surface water under present-day semi-arid environmental conditions. The Denver Formation contains several known and suspected geologic sources of selenium including: (1) lignite deposits; (2) tonstein partings; (3) organic-rich bentonite claystones; (4) salts formed as secondary weathering products; and possibly (5) the Cretaceous-Tertiary boundary. Organically complexed selenium and/or selenium-bearing pyrite in the enclosing claystones are likely the primary mineral sources of selenium in the Denver Formation, and correlations between concentration of dissolved selenium and dissolved organic carbon in groundwater indicate weathering and dissolution of organically complexed selenium from organic-rich claystone is a primary process mobilizing selenium. Secondary salts accumulated along fractures and bedding planes in the weathered zone are another potential geologic source of selenium, although their composition was not specifically addressed by the solids analyses. Results from this and previous work indicate that shallow groundwater and streams similarly positioned over Denver Formation claystone units at other locations in the Denver Basin also may contain concentrations of dissolved selenium greater than the Colorado aquatic-life standard or the drinking- water standard.
More South Platte River Basin coverage here.
USGS: Remediation Scenarios for Attenuating Peak Flows and Reducing Sediment Transport in Fountain Creek, Colorado, 2013April 21, 2014
Here’s the abstract from the USGS (Michael S. Kohn/John W. Fulton/Cory A. Williams/Robert W. Stogner, Sr.)
The U.S. Geological Survey (USGS) in cooperation with the Fountain Creek Watershed, Flood Control and Greenway District assessed remediation scenarios to attenuate peak flows and reduce sediment loads in the Fountain Creek watershed. To evaluate these strategies, the U.S. Army Corps of Engineers Hydrologic Engineering Center (HEC) hydrologic and hydraulic models were employed.
The U.S. Army Corps of Engineers modeling system HEC-HMS (Hydrologic Modeling System) version 3.5 was used to simulate runoff in the Fountain Creek watershed, Colorado, associated with storms of varying magnitude and duration. Rain-gage precipitation data and radar-based precipitation data from the April 28–30, 1999, and September 14–15, 2011, storm events were used in the calibration process for the HEC-HMS model. The curve number and lag time for each subwatershed and Manning’s roughness coefficients for each channel reach were adjusted within an acceptable range so that the simulated and measured streamflow hydrographs for each of the 12 USGS streamgages approximated each other.
The U.S. Army Corps of Engineers modeling system HEC-RAS (River Analysis System) versions 4.1 and 4.2 were used to simulate streamflow and sediment transport, respectively, for the Fountain Creek watershed generated by a particular storm event. Data from 15 USGS streamgages were used for model calibration and 7 of those USGS streamgages were used for model validation. The calibration process consisted of comparing the simulated water-surface elevations and the cross-section-averaged velocities from the model with those surveyed in the field at the cross section at the corresponding 15 and 7 streamgages, respectively. The final Manning’s roughness coefficients were adjusted between –30 and 30 percent at the 15 calibration streamgages from the original left, right, and channel-averaged Manning’s roughness coefficients upon completion of calibration.
The U.S. Army Corps of Engineers modeling system HEC-RAS version 4.2 was used to simulate streamflow and sediment transport for the Fountain Creek watershed generated by a design-storm event. The Laursen-Copeland sediment-transport function was used in conjunction with the Exner 5 sorting method and the Ruby fall-velocity method to predict sediment transport. Six USGS streamgages equipped with suspended-sediment samplers were used to develop sediment-flow rating curves for the sediment-transport-model calibration. The critical Shields number in the Laursen-Copeland sediment-transport function and the volume of sediment available at a given cross section were adjusted during the HEC-RAS sediment-model calibration process.
HEC-RAS model simulations used to evaluate the 14 remediation scenarios were based on unsteady-state streamflows associated with a 24-hour, 1-percent annual exceedance probability (100-year) National Oceanic and Atmospheric Administration Type II precipitation event. Scenario 0 represents the baseline or current conditions in the watershed and was used to compare the remaining 13 scenarios. Scenarios 1–8 and 12 rely on side-detention facilities to reduce peak flows and sediment transport. Scenario 9 has a diversion channel, and scenario 10 has a reservoir. Scenarios 11 and 13 incorporate channel armoring and channel widening, respectively. Scenarios 8 and 10, the scenario with the most side-detention facilities, and the scenario with the reservoir, respectively, were the most effective at reducing sediment transport and peak flow at the Pueblo, Colorado, streamgage. Scenarios 8 and 10 altered the peak flow by –58.9 and –56.4 percent, respectively. In turn, scenarios 8 and 10 altered the sediment transport by –17.7 and –62.1 percent, respectively.
More Fountain Creek coverage here.
USGS: Cross-ecosystem impacts of stream pollution reduce resource and contaminant flux to riparian food websFebruary 28, 2014
Click here to go to the Ecological Society of America website to download a copy of the report. Here’s the pitch:
The effects of aquatic contaminants are propagated across ecosystem boundaries by aquatic insects that export resources and contaminants to terrestrial food webs; however, the mechanisms driving these effects are poorly understood. We examined how emergence, contaminant concentration, and total contaminant flux by adult aquatic insects changed over a gradient of bioavailable metals in streams and how these changes affected riparian web-building spiders. Insect emergence decreased 97% over the metal gradient, whereas metal concentrations in adult insects changed relatively little. As a result, total metal exported by insects (flux) was lowest at the most contaminated streams, declining 96% among sites. Spiders were affected by the decrease in prey biomass, but not by metal exposure or metal flux to land in aquatic prey. Aquatic insects are increasingly thought to increase exposure of terrestrial consumers to aquatic contaminants, but stream metals reduce contaminant flux to riparian consumers by strongly impacting the resource linkage. Our results demonstrate the importance of understanding the contaminant-specific effects of aquatic pollutants on adult insect emergence and contaminant accumulation in adults to predict impacts on terrestrial food webs.
Credit: Johanna M. Kraus, Travis S. Schmidt, David M. Walters, Richard B. Wanty, Robert E. Zuellig, and Ruth E. Wolf
More USGS coverage here.
USGS: Characterization of Hydrodynamic and Sediment Conditions in the Lower Yampa River at Deerlodge Park, East Entrance to Dinosaur National Monument, Northwest Colorado, 2011February 23, 2014
Here’s the abstract from the USGS (Cory A. Williams):
The Yampa River in northwestern Colorado is the largest, relatively unregulated river system in the upper Colorado River Basin. Water from the Yampa River Basin continues to be sought for a number of municipal, industrial, and energy uses. It is anticipated that future water development within the Yampa River Basin above the amount of water development identified under the Upper Colorado River Endangered Fish Recovery Implementation Program and the Programmatic Biological Opinion may require additional analysis in order to understand the effects on habitat and river function. Water development in the Yampa River Basin could alter the streamflow regime and, consequently, could lead to changes in the transport and storage of sediment in the Yampa River at Deerlodge Park. These changes could affect the physical form of the reach and may impact aquatic and riparian habitat in and downstream from Deerlodge Park.
The U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board, began a study in 2011 to characterize the current hydrodynamic and sediment-transport conditions for a 2-kilometer reach of the Yampa River in Deerlodge Park. Characterization of channel conditions in the Deerlodge Park reach was completed through topographic surveying, grain-size analysis of streambed sediment, and characterization of streamflow properties. This characterization provides (1) a basis for comparisons of current stream functions (channel geometry, sediment transport, and stream hydraulics) to future conditions and (2) a dataset that can be used to assess channel response to streamflow alteration scenarios indicated from computer modeling of streamflow and sediment-transport conditions.
More USGS coverage here.
Fourteen monitoring wells were sampled by the U.S. Geological Survey, in cooperation with the Bureau of Land Management, to better understand the chemistry and age of groundwater in the Piceance structural basin in Rio Blanco County, Colorado, and how they may relate to the development of underlying natural-gas reservoirs. Natural gas extraction in the area has been ongoing since at least the 1950s, and the area contains about 960 producing, shut-in, and abandoned natural-gas wells.
Here’s the release from the USGS (Jon Campbell/Leonard Konikow):
A new U.S. Geological Survey study documents that the Nation’s aquifers are being drawn down at an accelerating rate.
Groundwater Depletion in the United States (1900-2008) comprehensively evaluates long-term cumulative depletion volumes in 40 separate aquifers (distinct underground water storage areas) in the United States, bringing together reliable information from previous references and from new analyses.
“Groundwater is one of the Nation’s most important natural resources. It provides drinking water in both rural and urban communities. It supports irrigation and industry, sustains the flow of streams and rivers, and maintains ecosystems,” said Suzette Kimball, acting USGS Director. “Because groundwater systems typically respond slowly to human actions, a long-term perspective is vital to manage this valuable resource in sustainable ways.”
To outline the scale of groundwater depletion across the country, here are two startling facts drawn from the study’s wealth of statistics. First, from 1900 to 2008, the Nation’s aquifers, the natural stocks of water found under the land, decreased (were depleted) by more than twice the volume of water found in Lake Erie. Second, groundwater depletion in the U.S. in the years 2000-2008 can explain more than 2 percent of the observed global sea-level rise during that period.
Since 1950, the use of groundwater resources for agricultural, industrial, and municipal purposes has greatly expanded in the United States. When groundwater is withdrawn from subsurface storage faster than it is recharged by precipitation or other water sources, the result is groundwater depletion. The depletion of groundwater has many negative consequences, including land subsidence, reduced well yields, and diminished spring and stream flows.
While the rate of groundwater depletion across the country has increased markedly since about 1950, the maximum rates have occurred during the most recent period of the study (2000–2008), when the depletion rate averaged almost 25 cubic kilometers per year. For comparison, 9.2 cubic kilometers per year is the historical average calculated over the 1900–2008 timespan of the study.
One of the best known and most investigated aquifers in the U.S. is the High Plains (or Ogallala) aquifer. It underlies more than 170,000 square miles of the Nation’s midsection and represents the principal source of water for irrigation and drinking in this major agricultural area. Substantial pumping of the High Plains aquifer for irrigation since the 1940s has resulted in large water-table declines that exceed 160 feet in places.
The study shows that, since 2000, depletion of the High Plains aquifer appears to be continuing at a high rate. The depletion during the last 8 years of record (2001–2008, inclusive) is about 32 percent of the cumulative depletion in this aquifer during the entire 20th century. The annual rate of depletion during this recent period averaged about 10.2 cubic kilometers, roughly 2 percent of the volume of water in Lake Erie.
More USGS coverage here.
From The Pueblo Chieftain (Chris Woodka):
Wells in the Arkansas Valley protected the agriculture economy in 2012, but reduced pumping levels this year are likely to hurt farming if weather conditions don’t improve. “Wells provided a one-year hedge against drought,” Water Division 2 Engineer Steve Witte told the Lower Arkansas Valley Water Conservancy District board Wednesday. “To quote Dale Mauch (a Lamar-area farmer quoted in The Pueblo Chieftain last summer): ‘If you’ve got a well, you’ve got a crop.’ ” This year, the situation is worse for farmers who rely on wells. Because of in-state shortfalls, pumping levels have been curtailed for most farmers. Unless farmers use their own surface rights to augment wells, pumping levels will be at only 10 to 30 percent of normal, with many farmers forced to shut off the pumps completely.
Last year, farmers pumped about 110,000 acrefeet of water (36 billion gallons), which was roughly three-fourths of the historical average prior to restrictions. The farm economy suffered much more, however, because of other factors.
During the drought of 2011-12, soil moisture plummeted, a trend that has continued since 2000. There also was less water available to surface ditches in both years.
Another problem for farmers will be increased transit loss as water from storage is released to headgates downstream. Normal loss from Pueblo Dam to the Rocky Ford area would be about 12 percent, but with river levels lower, it increases to 50 percent, Witte said.
One ray of hope offered at the meeting is a steadily increasing snowpack that is approaching nearly normal levels at a few sites in the mountains. Statewide, snowpack was about 82 percent of normal Wednesday, 73 percent in the Arkansas River basin, but 94 percent in the Upper Colorado basin, which provides supplemental water to Arkansas River users.
However, snowpack in the Purgatoire River basin, which helps farmers below John Martin Dam, is far below average.
Reservoir levels are well below 2012, and at 2003 levels for Turquoise and Twin Lakes. Lake Pueblo is at 88 percent of normal, better than it was in 2003, after drought had tapped out water supplies.
From The Pueblo Chieftain (Chris Woodka):
A water quality study spawned 10 years ago is focusing on finding causes for sedimentation and loading of harmful elements like selenium and uranium into the Arkansas River. “The real desire is to assist resource managers to find the source of a problem and attack it there, rather than put an ineffective plan in place,” said David Mau, head of the U.S. Geological Survey Pueblo office. He spoke at Wednesday’s meeting of the Lower Arkansas Valley Water Conservancy District.
The study began through a 2003 agreement among Aurora, the Southeastern Colorado Water Conservancy District and the Upper Arkansas Water Conservancy District.
The water resources group also includes Colorado Springs Utilities, the Pueblo Board of Water Works and the Lower Ark district. Aurora provided the initial funding.
The purpose of the study was to establish a water quality baseline before large projects like the Preferred Storage Options Plan, Southern Delivery System and Arkansas Valley Conduit went online. The USGS cataloged existing data on the river.
A 2009-11 study looked at two threatened reaches of the Arkansas River: from Canon City to Lake Pueblo, and from Lake Pueblo to La Junta. Loading of solids and uranium were found in both reaches, while heavy loading of selenium from Fountain Creek was prevalent downstream.
Mau said studies will continue to pinpoint sources of the pollution to help minimize the impact on water quality as projects continue.
Here’s Circular 1384 from the United States Geological Service. Here’s the introduction to the report (Alley, W.M./Evenson, E.J./Barber, N.L./Bruce, B.W./Dennehy, K.F./Freeman, M.C./Freeman, W.O./Fischer, J.M./Hughes, W.B./Kennen, J.G./Kiang, J.E./Maloney, K.O./Musgrove, MaryLynn/Ralston, Barbara/Tessler, Steven/Verdin, J.P):
The Omnibus Public Land Management Act of 2009 (Public Law 111-11) was passed into law on March 30, 2009. Subtitle F, also known as the SECURE Water Act, calls for the establishment of a “national water availability and use assessment program” within the U.S. Geological Survey (USGS). A major driver for this recommendation was that national water availability and use have not been comprehensively assessed since 1978.
This report fulfills a requirement to report to Congress on progress in implementing the national water availability and use assessment program, also referred to as the National Water Census. The SECURE Water Act authorized $20 million for each of fiscal years (FY) 2009 through 2023 for assessment of national water availability and use. The first appropriation for this effort was $4 million in FY 2011, followed by an appropriation of $6 million in FY 2012.
The National Water Census synthesizes and reports information at the regional and national scales, with an emphasis on compiling and reporting the information in a way that is useful to states and others responsible for water management and natural-resource issues. The USGS works with Federal and non-Federal agencies, universities, and other organizations to ensure that the information can be aggregated with other types of water-availability and socioeconomic information, such as data on food and energy production. To maximize the utility of the information, the USGS coordinates the design and development of the effort through the Federal Advisory Committee on Water Information.
A National Water Census is a complex undertaking, particularly because there are major gaps in the information needed to conduct such an assessment. To maximize progress, the USGS engaged stakeholders in a discussion of priorities and leveraged existing studies and program activities to enhance efforts toward the development of a National Water Census.
From The Pueblo Chieftain (Chris Woodka):
The census is being developed by the U.S. Geological Survey and will provide additional tools for water planners to use in making projections. The survey will look at competing demands for water resources and supply scenarios.
Water planning of this type already is occurring in water-short areas.
The Bureau of Reclamation last year completed an assessment on the Colorado River. The Colorado Water Conservation Board has developed decision-support systems for the Colorado River and Rio Grande basins and is working on similar models for the South Platte and Arkansas river basins.
Here’s a report about the recent USGS assessment of water quality at Lake Mead, from Bob Berwyn writing for the Summit County Citizens Voice. Here’s an excerpt:
Overall, the U.S. Bureau of Reclamation said that Lake Mead’s water quality is good and that fish populations are holding their own. Lake Mead is even providing habitat for an increasing number of birds. But the report also acknowledges that invasive quagga mussels have become the dominant lake-bottom organism, posing significant threat to the Lake Mojave and Lake Mead ecosystems. The report also acknowledges the long-term threat of climate change, which will bring reduced water supplies to the entire Colorado River Basin.
“While the Lake Mead ecosystem is generally healthy and robust, the minor problems documented in the report are all being addressed by the appropriate agencies, and are showing substantial improvement since the mid 1990′s,” said U.S. Geological Survey hydrologist Michael Rosen.
Major findings detailed in the report include the following:
Basic water-quality parameters are within good ranges of Nevada and Arizona standards and EPA lake criteria. Potential problems with nutrient balance, algae, and dissolved oxygen can occur at times and in some areas of Lake Mead. The Lake Mead-wide scope of monitoring provides a solid baseline to characterize water quality now and in the future. Legacy contaminants are declining due to regulations and mitigation efforts in Las Vegas Wash. Emerging contaminants, including endocrine disrupting compounds, are present in low concentrations. While emerging contaminants, such as pharmaceuticals, personal care products, or plasticizers have been documented to cause a number of health effects to individual fish, they are not seen at concentrations currently known to pose a threat to human health. In comparison to other reservoirs studied by the U.S. Environmental Protection Agency, Lake Mead is well within the highest or ‘good’ category for recreation and aquatic health. Lake Mead and Lake Mohave continue to provide habitat conditions that support a rich diversity of species within the water, along shorelines, and in adjacent drainage areas, including organisms that are both native and non-native to the Colorado River drainage. Sport fish populations appear stable and have reached a balance with reservoir operations over the past 20 years and are sufficient to support important recreational fishing opportunities. Native fish populations within Lake Mohave are declining, but the small native fish populations in Lake Mead are, stable without any artificial replenishment. Lake Mead and Lake Mohave provide important migration and wintering habitat for birds. Trends include increasing numbers of wintering bald eagles and nesting peregrine falcons. Lake Mead water-level fluctuations have produced a variety of shorebird habitats, but songbird habitats are limited. Although some contaminants have been documented in birds and eggs in Las Vegas Wash, mitigation efforts are making a positive change. Invasive quagga mussels have become the dominant lake-bottom organism and are a significant threat to the ecosystems of Lake Mead and Lake Mohave because they have potential to alter water quality and food-web dynamics. Although they increase water clarity, they can degrade recreational settings. Climate models developed for the Colorado River watershed indicate a high probability for longer periods of reduced snowpack and therefore water availability for the Lake Mead in the future. Federal, state and local agencies, and individuals and organizations interested the future of the water supply and demand imbalance are working together to examine strategies to mitigate future conditions.
‘Climate change is forcing plants and animals to shift where they live and grow more quickly’ — Bobby MagillDecember 18, 2012
One measure of Climate Change — constantly shifting vegetation — is the subject of a new report from the United States Geological Service, the National Wildlife Service and Arizona State University. Here’s the release.
Plant and animal species are shifting their geographic ranges and the timing of their life events – such as flowering, laying eggs or migrating – at faster rates than researchers documented just a few years ago, according to a technical report on biodiversity and ecosystems used as scientific input for the 2013 Third National Climate Assessment.
The report, Impacts of Climate Change on Biodiversity, Ecosystems, and Ecosystem Services, synthesizes the
scientific understanding of the way climate change is affecting ecosystems, ecosystem services and the diversity of species, as well as what strategies might be used by natural resource practitioners to decrease current and future risks. More than 60 federal, academic and other scientists, including the lead authors from the U.S. Geological Survey, the National Wildlife Federation and Arizona State University in Tempe, authored the assessment.
“These geographic range and timing changes are causing cascading effects that extend through ecosystems, bringing together species that haven’t previously interacted and creating mismatches between animals and their food sources,” said Nancy Grimm, a scientist at ASU and a lead author of the report.
Grimm explained that such mismatches in the availability and timing of natural resources can influence species’ survival; for example, if insects emerge well before the arrival of migrating birds that rely on them for food, it can adversely affect bird populations. Earlier thaw and shorter winters can extend growing seasons for insect pests such as bark beetles, having devastating consequences for the way ecosystems are structured and function. This can substantially alter the benefits people derive from ecosystems, such as clean water, wood products and food.
“The impact of climate change on ecosystems has important implications for people and communities,” said Amanda Staudt, a NWF climate scientist and a lead author on the report. “Shifting climate conditions are affecting valuable ecosystem services, such as the role that coastal habitats play in dampening storm surge or the ability of our forests to provide timber and help filter our drinking water.”
Another key finding is the mounting evidence that population declines and increased extinction risks for some plant and animal species can be directly attributed to climate change. The most vulnerable species are those already degraded by other human-caused stressors such as pollution or exploitation, unable to shift their geographic range or timing of key life events, or that have narrow environmental or ecological tolerance. For example, species that must live at high altitudes or live in cold water with a narrow temperature range, such as salmon, face an even greater risk due to climate change.
“The report clearly indicates that as climate change continues to impact ecological systems, a net loss of global species’ diversity, as well as major shifts in the provision of ecosystem services, are quite likely,” said Michelle Staudinger, a lead author of the report and a USGS and University of Missouri scientist.
For example, she added, climate change is already causing shifts in the abundance and geographic range of economically important marine fish. “These changes will almost certainly continue, resulting in some local fisheries declining or disappearing while others may grow and become more valuable if fishing communities can find socially and economically viable ways to adapt to these changes.”
Natural resource managers are already contending with what climate change means for the way they approach conservation. For example, the report stated, land managers are now more focused on the connectivity of protected habitats, which can improve a species’ ability to shift its geographic range to follow optimal conditions for survival.
“The conservation community is grappling with how we manage our natural resources in the face of climate change, so that we can help our ecosystems to continue meeting the needs of both people and wildlife,” said Bruce Stein, a lead author of the report and director of climate adaptation at the National Wildlife Federation.
Other key findings of the report include:
Changes in precipitation and extreme weather events can overwhelm the ability of natural systems to reduce or prevent harm to people from these events. For example, more frequent heavy rainfall events increase the movement of nutrients and pollutants to downstream ecosystems, likely resulting not only in ecosystem change, but also in adverse changes in the quality of drinking water and a greater risk of waterborne-disease outbreaks.
Changes in winter have big and surprising effects on ecosystems and their services. Changes in soil freezing, snow cover and air temperature affect the ability of ecosystems to store carbon, which, in turn, influences agricultural and forest production. Seasonally snow-covered regions are especially susceptible to climate change because small precipitation or temperature shifts can cause large ecosystem changes. Longer growing seasons and warmer winters are already increasing the likelihood of pest outbreaks, leading to tree mortality and more intense, extensive fires. Decreased or unreliable snowfall for winter sports and recreation will likely cause high future economic losses.
The ecosystem services provided by coastal habitats are especially vulnerable to sea-level rise and more severe storms. The Atlantic and Gulf of Mexico coasts are most vulnerable to the loss of coastal protection services provided by wetlands and coral reefs. Along the Pacific coast, long-term dune erosion caused by increasing wave heights is projected to cause problems for communities and for recreational beach activities. However, other kinds of recreation will probably improve due to better weather, with the net effect being that visitors and tourism dollars will shift away from some communities in favor of others.
Climate change adaptation strategies are vital for the conservation of diverse species and effective natural resource policy and management. As more adaptive management approaches are developed, resource managers can enhance the country’s ability to respond to the impacts of climate change through forward-looking and climate science-informed goals and actions.
Ecological monitoring needs to be improved and better coordinated among federal and state agencies to ensure the impacts of climate change are adequately monitored and to support ecological research, management, assessment and policy. Existing tracking networks in the United States will need to improve coverage through time and in geographic area to detect and track climate-induced shifts in ecosystems and species.
Federal law requires that the U.S. Global Change Research Program submit an assessment of climate change and its impacts to the President and the Congress once every four years. Technical reports, articles and books – such as this report — underpin the corresponding chapters of the Third U.S. National Climate Assessment, due out in 2013. This technical report is available at the USGCRP website, as are other completed technical reports. Additional lead authors of this report include Shawn Carter, USGS: F. Stuart Chapin III, University of Alaska, Fairbanks; Peter Kareiva, The Nature Conservancy; and Mary Ruckelshaus, Natural Capital Project.
From the Fort Collins Coloradoan (Bobby Magill):
A changing climate is stressing out plants, animals and the ecosystems they inhabit to a greater degree than at any other period in human history, according to a U.S. Geological Survey, National Wildlife Federation and University of Arizona report released Tuesday. The report will be part of the federal government’s 2013 National Climate Assessment.
Climate change is forcing plants and animals to shift where they live and grow more quickly than expected, the report concludes. Mountain species are moving upward in elevation at rates up to three times greater than scientists estimated because of a warming climate.
Biological diversity across the planet is expected to decline while extreme weather could mean heavy rains in places that aren’t accustomed to them.
More USGS coverage here.
What does 42,300 CFS look like? River-level view from this week’s high-flow experiment at Glen Canyon DamNovember 21, 2012
Recreation Industry Praises High Flow Release at Glen Canyon: Target maximum release is 42,300 cfs #CORiverNovember 20, 2012
Protect The Flows (@ProtectFlows) November 19, 2012
Reclamation (@usbr) November 20, 2012
Here’s the release from Protect the Flows (Molly Mugglestone):
Today, the U.S. Department of the Interior triggered the first “high-flow experimental release” at Glen Canyon Dam since 2008.
According to Interior, the release, which will last nearly five days, is part of a new long-term protocol to meet water and power needs, allow better conservation of sediment downstream, and better control the non-native fish population from preying on other species. The high release flows are geared to mimic historical pre-dam spring floods and runoffs.
Protect the Flows member George Wendt, President and CEO of OARS Outdoor Adventure River Specialists, which has been providing Grand Canyon rafting experiences since 1969, made the following statement in response:
“The water released this week is the first in a long term plan that will help to build new camping beaches in the Grand Canyon, and ultimately, will improve the canyon experience for boaters supporting a $26 billion recreation economy that depends on the Colorado River. We applaud the Department of Interior for taking these important steps that take into consideration the long term use of the canyon by boaters. This release shows an attempt at good stewardship of the area and is an example of how the conservation community and those who love to recreate on the river worked together with the Department of Interior on a solution that both fish and rafters will benefit from for years to come.”
Here’s the release from the U.S. Department of Interior (Blake Androff/Lisa Iams):
Secretary of the Interior Ken Salazar today triggered the first “high-flow experimental release” at Glen Canyon Dam, under a new experimental long-term protocol to better distribute sediment to conserve downstream resources, while meeting water and power needs and allowing continued scientific experimentation, data collection, and monitoring on the Colorado River.
The new protocol calls for experimental releases from the dam through 2020 to send sediment downstream to rebuild sandbars, beaches, and backwaters. The rebuilt areas will provide key wildlife habitat, enhance the aquatic food base, protect archeological sites, and create additional camping opportunities in the canyon.
“This is truly an historic milestone for the Colorado River, Grand Canyon National Park, and the United States Bureau of Reclamation,” said Salazar. “It was an honor to open the door to a new era for Glen Canyon Dam operations and the ecology of Glen Canyon National Recreation Area and Grand Canyon National Park – a new era in which we realize that the goals of water storage, delivery and hydropower production are compatible with improving and protecting the resources of the Colorado River.”
The new protocol is built on more than 16 years of scientific research and experimentation conducted under the Glen Canyon Dam Adaptive Management Program. The Department translated the research into a flexible framework that enables scientists to determine, based on the best available science, when the conditions are right to conduct these releases to maximize the ecosystem benefits along the Colorado River corridor in Glen Canyon National Recreation Area and Grand Canyon National Park.
With the Glen Canyon Powerplant running at full capacity, Secretary Salazar opened the river outlet tubes at noon, releasing additional flows that will increase throughout the day until a maximum release of approximately 42,300 cubic-feet-per-second is reached. These releases will continue for nearly five days based on the parameters specified in the protocol and the volume of sediment deposited by the Paria River since late July, which scientists estimate is approximately 500,000 metric tons, enough to fill a football field 230 feet deep.
Through the foundation laid by the protocol, annual experiments can be conducted through 2020 to evaluate the effectiveness of multiple high flow experimental (HFE) releases in rebuilding and conserving sandbars, beaches, and associated backwater habitats that have been lost or depleted since the dam’s construction and operation. The protocol identifies the conditions under which a high flow release will likely yield the greatest conservation and beneficial use of sediment deposited by inflows from Colorado River tributaries as a result of rainstorms, monsoons, and snowmelt.
“Favorable sediment conditions in the system only occur periodically, so the ability to respond quickly and make the best use of those deposits when the time is right is essential,” said Anne Castle, Assistant Secretary of the Interior for Water and Science. “Today’s experimental release under the new protocol represents a significant milestone in our collective ability to be nimble and responsive to on-the-ground conditions for the benefit of downstream resources.”
HFE releases simulate natural flood conditions that suspend and redeposit sand stored in the river channel to provide key wildlife habitat—including habitat for the endangered humpback chub, protect archaeological sites, enhance riparian vegetation, maintain or increase recreation opportunities, and improve the wilderness experience along the Colorado River in Glen and Grand canyons. Single experimental releases were conducted in 1996, 2004, and 2008, and included extensive scientific research, monitoring, and data collection by the U.S. Geological Survey’s Grand Canyon Monitoring and Research Center, the Bureau of Reclamation, the National Park Service, and the U.S Fish and Wildlife Service.
“These high-flow releases, a new paradigm in water management, recognize that there are hugely beneficial impacts to river ecology from releasing the requisite water needed downstream in large pulses, rather than uniformly throughout the year,” said USGS Director Marcia McNutt. “In the arid West, non-uniform flow better mimics the natural environment in which the plants and animals flourished.”
This scientific process will continue and the knowledge gained from today’s experimental high flow will be used to make further refinements in determining the optimal timing, duration, frequency, and conditions for future releases as well as to inform other management actions on the river.
“As the 1992 Grand Canyon Protection Act emphasizes, the resources of the Grand Canyon are fragile, and conservation of those resources can only be achieved through wise management by today’s leaders,” said National Park Service Director Jonathan B. Jarvis. “Today’s event marks the beginning of the next generation of wisdom for managing this special place. We have only one Grand Canyon. We want to thank the Secretary for his leadership and conservation of this special place now and into the future.”
The protocol represents one of two important milestones in the history of the Colorado River. The second, a program to control non-native fish species, provides a framework for actions and research to protect native endangered fish in the river downstream of the dam. The finalization of both efforts involved extensive government-to-government consultation with Native American tribes to ensure implementation of the programs in a manner that respects tribal perspectives.
“The Bureau of Indian Affairs supports the cooperating tribes’ active involvement in the Glen Canyon Dam Adaptive Management Program,” said Assistant Secretary for Indian Affairs Kevin Washburn. “Many of their insights were incorporated into the process leading to the HFE event. Their strong connections to the Grand Canyon, including their cultural, historic and religious ties, give them a unique perspective on this national treasure. I want to thank the tribes for their long stewardship and their full participation in this important effort to conserve and protect the Colorado River ecosystem.”
The additional water released as part of the HFE is part of the annual water delivery to the Lake Mead. “The volume of water we are releasing during this high flow experiment does not change the overall volume of water delivery in the 2013 water year,” said Reclamation Commissioner Michael L. Connor. “The current operations plan based on forecast data calls for releasing 8.23 million acre-feet of water from the dam to meet delivery obligations to the Lower Colorado River Basin and Mexico. The experimental flows are included in that total annual volume and will be offset by adjustments to the monthly release volumes throughout the rest of the water year.”
“This new protocol developed by Reclamation will protect both the Grand Canyon and the delivery of water for communities, agriculture and industry,” Salazar noted. “We are taking a practical approach. If, for any reason, the new high-flow experiments do not yield the positive results we anticipate, we have the ability to change and adjust future flows.”
In addition to the opportunities for HFE releases made possible under the protocol, Secretary Salazar has initiated the first comprehensive analysis of Glen Canyon Dam operations since 1996. The Glen Canyon Dam Long-Term Experimental and Management Plan Environmental Impact Statement will build on information obtained through the Adaptive Management Program and activities conducted under the protocol to analyze a broad scope of dam operations and other related activities. The goal is to determine specific alternatives that could be implemented to improve and protect downstream resources while adhering to applicable laws. Reclamation and the National Park Service are jointly developing the LTEMP EIS, which will ultimately integrate and further refine actions conducted under the protocol.
Here’s a technical description of what the USGS hopes to accomplish (Jack Schmidt/Barbara Wilcox). Here’s an excerpt:
“Throughout summer and fall 2012, the USGS research team developed, and continually revised, estimates of the total amount of sand and of mud delivered by the Paria River, as well as estimating the fate of that fine sediment as it was transported further downstream through the Grand Canyon,” said Jack Schmidt, chief of the USGS Grand Canyon Monitoring and Research Center. “These data are the scientific foundation on which the planned high-flow experiment is based. Without the estimates of the amount of sand and mud delivered from tributaries, it would not have been possible to implement the Protocol for these high flow experiments. The entire program of utilizing small controlled floods to rehabilitate the Grand Canyon ecosystem depends on state-of-the-science monitoring efforts by the USGS to measure sediment transport rates in real time and to provide those data to the Bureau of Reclamation and to other agencies.
“The USGS program of measuring and reporting sand and mud transport in real time and in such a challenging environment is unprecedented in the scientific management of rivers,” Schmidt said.
USGS data show that the Paria River delivered at least 593,000 tons of sand to the Colorado River between late July and the end of October 2012 – enough to fill a building the size of a 100-yard NFL football field about 24 stories high. Long-term measurements show that this amount is about 26 percent less than delivered by the Paria in an average year, but is still sufficient to trigger a small controlled flood intended to rehabilitate the downstream ecosystem.
From the Associated Press via Las Vegas Review-Journal:
Interior Secretary Ken Salazar opened the river outlet tubes at noon and called it “an historic milestone” and “a new era in which we realize that the goals of water storage, delivery and hydropower production are compatible with improving and protecting the resources of the Colorado River.” The peak flow will last 24 hours from Monday night into Tuesday, and the river will run high for five days…
The experiment could hurt next year’s fishing – and complicate hydropower production and water storage – in the name of a more environmentally correct river…
Previous experiments in 1996, 2004 and 2008 were one-time fact-finding missions instead of fundamental shifts in river management.
“This (Obama) administration can be patted on the back and thanked for doing what we’ve been trying to do, seriously, for 15 years,” Lash added.
The previous experiments yielded mixed results, partly because a return to up-and-down flows timed partly to regional summer hydropower needs wiped out many of the new beaches and sandbars.
Advocates hope the effects will be longer lasting if these floods come more regularly and if a longer-term Interior Department planning effort leads to steadier flows through the summers.
But critics say that there’s little environmental benefit and that it comes at a cost.
In comments submitted to the Interior Department before the decision to go forward with regular flushes, the Colorado River Energy Distributors Association, a group of nonprofit energy utilities, noted that previous springtime flood experiments helped boost the population of non-native trout that feed on the endangered humpback chub.
It’s no surprise that people settle near surface water. Here’s the release from the United States Geological Service (James Coles/Kara Capelli):
The loss of sensitive species in streams begins to occur at the initial stages of urban development, according to a new study by the USGS. The study found that streams are more sensitive to development than previously understood.
“We tend not to think of waterways as fragile organisms, and yet that is exactly what the results of this scientific investigation appear to be telling us,” said USGS Director Marcia McNutt. “Streams are more than water, but rather communities of interdependent aquatic life, the most sensitive of which are easily disrupted by urbanization.”
Contaminants, habitat destruction, and increasing streamflow flashiness resulting from urban development can degrade stream ecosystems and cause degradation downstream with adverse effects on biological communities and on economically valuable resources, such as fisheries and tourism.
For example, by the time urban development had approached 20 percent in watersheds in the New England area, the aquatic invertebrate community had undergone a change in species composition of about 25 percent.
The study also found that the health of highly-degraded streams can be improved by implementing management actions that are designed to reduce specific stressors.
“Biological communities were not resistant to even low levels of urban development. In the study sensitive invertebrate species were being lost over the initial stages of development in relatively undisturbed watersheds,” said Dr. Gerard McMahon, lead scientist on the study. “Understanding how stream ecosystems are impacted by urban development can assist in the development of management actions to protect and rehabilitate urban stream ecosystems.”
Multiple streams in nine metropolitan areas across the continental U.S. were sampled to assess the effects of urban development on stream ecosystems. Study areas include Atlanta, Ga., Birmingham, Ala., Boston, Mass., Dallas, Texas, Denver, Colo., Milwaukee, Wis., Portland, Ore., Raleigh, N.C., and Salt Lake City, Utah.
The study also found that the effects of urbanization on the biological community vary geographically depending on the predominant land cover and the health of the community prior to urban development. In the study, the greatest loss of sensitive species occurred in Boston, Portland, Salt Lake City, Birmingham, Atlanta, and Raleigh metropolitan areas, where the predominant land cover was forested prior to urban development. The smallest loss of sensitive species occurred in Denver, Dallas, and Milwaukee metropolitan areas where land cover was primarily agriculture before urban development.
“The reason for this difference was not because biological communities in the Denver, Dallas, and Milwaukee areas are more resilient to stressors from urban development, but because the biological communities had already lost sensitive species to stressors from pre-urban agricultural land use activities,” said McMahon.
Although urban development creates multiple stressors, such as an increase in concentrations of insecticides, chlorides, and nutrients, that can degrade stream health—no single factor was universally important in explaining the effects of urban development on stream ecosystems. The USGS developed an innovative modeling tool to predict how different combinations of urban-related stressors affect stream health. This tool, initially developed for the New England area, can provide insights on how watershed management actions to improve one or more of these stressors may increase the likelihood of obtaining a desired biological condition.
The effects of urbanization on streams, including information about this and past studies, as well as graphics and maps, and videos can be online.
Results of this nationwide study and details about the effects of urbanization on the nine metropolitan areas can be found in a new USGS publication titled, “Effects of urban development on stream ecosystems in nine metropolitan study areas across the United States.”
Management strategies used throughout the U.S. to reduce the impacts of urban development on stream ecosystems are described in a new USGS report written in partnership with the Center for Watershed Protection in Maryland titled, “Strategies for Managing the Effects of Urban Development on Streams.”
This study was done by the USGS National Water-Quality Assessment Program, which conducts regional and national assessments of the nation’s water quality to provide an understanding of water-quality conditions, whether conditions are getting better or worse over time, and how natural features and human activities affect those conditions.
More USGS coverage here.
Snake River: USGS — Warmer Temperatures Likely Driving Increase of Metal Concentrations in Rocky Mountain WatershedSeptember 13, 2012
Here’s the release the United States Geological Survey (Heidi Koontz/Jim Scott):
Warmer air temperatures since the 1980s may explain significant increases in zinc and other metal concentrations of ecological concern in a Rocky Mountain watershed, according to a new study published in the journal Environmental Science and Technology, led by the U.S. Geological Survey and the University of Colorado, Boulder.
Rising concentrations of zinc and other metals in the upper Snake River just west of the Continental Divide near Keystone, Colo., may be the result of falling water tables, melting permafrost, and accelerating mineral weathering rates, all driven by warmer air temperatures in the watershed. Researchers observed a fourfold increase in dissolved zinc over the last 30 years during the month of September.
“This study provides another fascinating, and troubling, example of a cascading impact from climate warming as the rate of temperature-dependent chemical reactions accelerate in the environment, leaching metals into streams,” said USGS Director Marcia McNutt. “The same concentration of metals in the mountains that drew prospectors to the Rockies more than a century ago are now the source of toxic trace elements that are harming the environment as the planet warms.”
Increases in metals were seen in other months as well, with lesser increases seen during the high-flow snowmelt period. During the study period, local mean annual and mean summer air temperatures increased at a rate of 0.2-1.2 degrees Celsius per decade.
Generally, high concentrations of dissolved metals in the upper Snake River watershed are the result of acid rock drainage, or ARD, formed by natural weathering of pyrite and other metal-rich sulfide minerals in the bedrock. Weathering of pyrite forms sulfuric acid through a series of chemical reactions, and mobilizes metals like zinc from minerals in the rock and carries these metals into streams.
Increased sulfate and calcium concentrations observed over the study period lend weight to the hypothesis that the increased zinc concentrations are due to acceleration of pyrite weathering. The potential for comparable increases in metals in similar Western watersheds is a concern because of impacts on water resources, fisheries and stream ecosystems. Trout populations in the lower Snake River, for example, appear to be limited by the metal concentrations in the water, said USGS scientist Andrew Todd, lead researcher on the project.
“Acid rock drainage is a significant water quality problem facing much of the Western United States,” Todd said. “It is now clear that we need to better understand the relationship between climate and ARD as we consider the management of these watersheds moving forward.”
In cases where ARD is linked directly with past and present mining activities it is called acid mine drainage, or AMD. Another Snake River tributary, Peru Creek, is largely devoid of life due to AMD generated from the abandoned Pennsylvania Mine and smaller mines upstream, and has become a target for potential remediation efforts.
The Colorado Division of Reclamation Mining and Safety, in conjunction with other local, state and federal partners, is conducting underground exploration work at the mine to investigate the sources of heavy metals-laden water draining from the adit. The study conducted by Todd and colleagues has implications in such efforts because it suggests that establishing attainable clean-up objectives could be difficult if natural background metal concentrations are a “moving target.”
Collaborators include USGS, CU Boulder and the Institute of Arctic and Alpine Research (INSTAAR). The data analyzed for the study came from INSTAAR, the USGS and the U.S. Environmental Protection Agency.
From the Summit Daily News (Paige Blankenbuehler):
Rising concentrations of zinc and other metals in the upper Snake River west of the Continental Divide near Keystone may be the result of falling water tables, melting permafrost and accelerating mineral- weathering rates — all driven by warmer air temperatures in the watershed…
High concentrations of dissolved metals in the upper Snake River watershed are the result of acid rock drainage, according to the research. The drainage is a result from past and present mining activities.
More water pollution coverage here.
Here’s the release from the United States Geological Survey (Keelin R. Schaffrath):
Elevated levels of dissolved solids in water (salinity) can result in numerous and costly issues for agricultural, industrial, and municipal water users. The Colorado River Basin Salinity Control Act of 1974 (Public Law 93–320) authorized planning and construction of salinity-control projects in the Colorado River Basin. One of the first projects was the Lower Gunnison Unit, a project to mitigate salinity in the Lower Gunnison and Uncompahgre River Basins.
In cooperation with the Bureau of Reclamation (USBR), the U.S. Geological Survey conducted a study to quantify changes in salinity in the Gunnison River Basin. Trends in salinity concentration and load during the period water years (WY) 1989 through 2004 (1989–2004) were determined for 15 selected streamflow-gaging stations in the Gunnison River Basin. Additionally, trends in salinity concentration and load during the period WY1989 through 2007 (1989–2007) were determined for 5 of the 15 sites for which sufficient data were available. Trend results also were used to identify regions in the Lower Gunnison River Basin (downstream from the Gunnison Tunnel) where the largest changes in salinity loads occur. Additional sources of salinity, including residential development (urbanization), changes in land cover, and natural sources, were estimated within the context of the trend results. The trend results and salinity loads estimated from trends testing also were compared to USBR and Natural Resources Conservation Service (NRCS) estimates of off-farm and on-farm salinity reduction from salinity-control projects in the basin. Finally, salinity from six additional sites in basins that are not affected by irrigated agriculture or urbanization was monitored from WY 2008 to 2010 to quantify what portion of salinity may be from nonagricultural or natural sources.
In the Upper Gunnison area, which refers to Gunnison River Basin above the site located on the Gunnison River below the Gunnison Tunnel, estimated mean annual salinity load was 110,000 tons during WY 1989–2004. Analysis of both study periods (WY 1989–2004 and WY 1989–2007) showed an initial decrease in salinity load with a minimum in 1997. The net change over either study period was only significant during WY 1989–2007. Salinity load significantly decreased at the Gunnison River near Delta by 179,000 tons during WY 1989–2004. Just downstream, the Uncompahgre River enters the Gunnison River where there also was a highly significant decrease in salinity load of 55,500 tons. The site that is located at the mouth of the study area is the Gunnison River near Grand Junction where the decrease was the largest. Salinity loads decreased by 247,000 tons during WY 1989–2004 at this site though the decrease attenuated by 2007 and the net change was a decrease of 207,000 tons.
The trend results presented in this study indicate that the effect of urbanization on salinity loads is difficult to discern from the effects of irrigated agriculture and that natural sources contribute a fraction of the total salinity load for the entire basin. Based on the calculated yields and geology, 23–63 percent of the estimated annual salinity load was from natural sources at the Gunnison River near Grand Junction during WY 1989–2007. The largest changes in salinity load occurred at the Gunnison River near Grand Junction as well as the two sites located in Delta: the Gunnison River at Delta and the Uncompahgre River at Delta. Those three sites, especially the two sites at Delta, were the most affected by irrigated agriculture, which was observed in the estimated mean annual loads. Irrigated acreage, especially acreage underlain by Mancos Shale, is the target of salinity-control projects intended to decrease salinity loads.
The NRCS and the USBR have done the majority of salinity control work in the Lower Gunnison area of the Gunnison River Basin, and the focus has been in the Uncompahgre River Basin and in portions of the Lower Gunnison River Basin (downstream from the Gunnison Tunnel). According to the estimates from the USBR and NRCS, salinity-control projects may be responsible for a reduction of 117,300 tons of salinity as of 2004 and 142,000 tons as of 2007 at the Gunnison River near Grand Junction, Colo. (streamflow-gaging station 09152500). USBR and NRCS estimates account for all but 130,000 tons in 2004 and 65,000 tons in 2007 of salinity load reduction. The additional reduction could be a reduction in natural salt loading to the streams because of land-cover changes during the study period. It is possible also that the USBR and NRCS have underestimated changes in salinity loads as a result of the implementation of salinity-control projects.
Click here to download the report.
Remember all the way back to water year 2011 when Colorado’s reservoirs mostly filled to the brim? Here’s the Streamflow of 2011 — Water Year Summary from the United States Geological Survey (Xiaodong Jian/David M. Wolock/Harry F. Lins/Steve Brady).
For you numbers junkies the document should be a great read to take along next time you’re sitting under the cottonwoods by your favorite stream.
Here’s the introduction:
The maps and graph in this summary describe streamflow conditions for water year 2011 (October 1, 2010, to September 30, 2011) in the context of the 82-year period from 1930 through 2011, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey’s (USGS) National Streamflow Information Program (http://water.usgs.gov/nsip/). The period 1930–2010 was used because, prior to 1930, the number of streamgages was too small to provide representative data for computing statistics for most regions of the country.
In the summary, reference is made to the term “runoff,” which is the depth to which a river basin, State, or other geographic area would be covered with water if all the streamflow within the area during a single year was uniformly distributed upon it. Runoff quantifies the magnitude of water flowing through the Nation’s rivers and streams in measurement units that can be compared from one area to another. Each of the maps and graphs can be expanded to a larger view by clicking on the image. In all of the graphics, a rank of 1 indicates the highest flow of all years analyzed.
More USGS coverage here.
Update: It was early this morning when I first posted this and I neglected to point out that they have mapped selected stream gages as well.
Sometimes it’s nice to look at the calls on the river graphically. Thanks to the United Water and Sanitation District you don’t have to haul out your straight line diagram for the South Platte Basin. They’ve built an online map with current river calls.
Click on the thumbnail graphic for a screen shot of this morning’s map.
Here’s the release from United Water and Sanitation:
United Water and Sanitation District has unveiled a first-of-its-kind South Platte River Basin map that allows water users and providers throughout the Front Range to get real-time, visual information about the status of the South Platte River and its tributaries.
The map (http://map.unitedwaterdistrict.com/”>) aggregates hourly data from a variety of sources, including the United States Geological Survey (USGS) and the Colorado Division of Water Resources, providing comprehensive streamflow information from the South Platte River Basin. Map users can scroll over dozens of river locations to get valuable and timely information, including:
- River height (ft)
- Streamflow rates in cubic feet per second(cfs)
- Active calls on the river
- Apparent dry-up points
“This map allows users to see the supply side along with the demand side of the river basin as conditions change,” said Josh Shipman, asset manager for United Water and Sanitation District. “We have taken a tremendous amount of data and put it in a visual, interactive format, making it easier for water users and providers to quickly and easily get information. It now only takes a few seconds to get information on the river that previously took hours to compile and compare.”
With numerous water rights and supply interests along the South Platte River basin, United Water anticipates a variety of interest in the map – from ditch companies and water districts to farmers and municipalities – particularly in a dry year like one we are currently experiencing.
“Ultimately this map allows any interested party to monitor real time, stream conditions to ensure they are receiving the full allocation of their call on the river,” said Ron von Lembke, chief of staff at United Water and Sanitation District. “But it can also be useful for water recreationalists such as kayakers and fishermen who are interested in water conditions related to their activities.”
The map encompasses all of the South Platte River basin – including each of the 16 Districts included in Water Division 1 of the Colorado Division of Water Resources(http://water.state.co.us/DWRIPub/DWR Maps/ColoradoRiverBasins.pdf) While there is potential to expand the map to other divisions throughout the state, United Water’s immediate focus will be on adding streamflow monitoring stations and select weather stations in these districts to further enhance its current functionality.
Here’s the release from the United States Geological Survey (J.V. Loperfido/D.M. Hogan):
Urbanization results in elevated stormwater runoff, greater and more intense streamflow, and increased delivery of pollutants to local streams and downstream aquatic systems such as the Chesapeake Bay. Stormwater Best Management Practices (BMPs) are used to mitigate these effects of urban land use by retaining large volumes of stormwater runoff (water quantity) and removing pollutants in the runoff (water quality). Current USGS research aims to understand how the spatial pattern and connectivity of stormwater BMPs affect water quantity and water quality in urban areas.
More stormwater coverage here.
The United States Geological Service is modeling the effects of climate change on various basins around the U.S. Here’s a release from the agency (Kara Capelli):
“We are unlikely to see a ‘water-as-usual’ future.” – Marcia McNutt, USGS Director
Arguably, the most important impacts of climate change – including those to ecosystems, agriculture, energy, and industry – will be tied to changes in water availability, especially as the world becomes increasingly water-stressed. It’s crucial that water managers understand the likely impacts of climate change, so that they can plan for new conditions and challenges.
How will your water be affected?
Understanding the impacts that climate change will have on water availability in specific regions and communities is a mammoth task. Water availability in every region, basin, and watershed will be affected differently, depending on the specific precipitation and hydrologic conditions in that area.
Also, for all of the models and technology we have available at our 21st century finger tips, weather patterns are still notoriously unpredictable. Forecasting future precipitation conditions is even more difficult, especially under new climate scenarios, and changes to weather patterns will vary across the country.
Complicating water availability predictions further, each basin has its own unique set of hydrologic and geologic features that affect how much water is available, where that water comes from, and how it flows through a system.
Little by little, though, scientists are beginning to build the information and tools to understand the nuanced effects of climate change to the Nation’s water resources.
USGS predicting changes to water availability in 14 basins across the Nation
In a first-of-its-kind study, scientists from the USGS have predicted changes to water resources for 14 different basins across the country.
First, the scientists downscaled vast climate models, in order to understand changes in temperature and precipitation specific to the 14 study basins. They then used USGS hydrologic models and streamgage information to project how water resources will be impacted by the changing weather patterns, taking into account specific hydrologic and geologic features in each basin, such as snowpack, drought, and groundwater conditions.
For example, the USGS models project that changes to snowpack in the Sprague River Basin in Oregon could cause annual peak streamflows to occur earlier in the spring as overall basin storage decreases. This means that managers may be forced to modify storage operation and reprioritize water delivery for environmental and human needs.
In many areas the biggest impacts to water resources will be a factor of reduced snowpack. For example snowpack in the headwaters of the Colorado River could affect the amount and timing of streamflow to the Colorado River and also impact important recreation areas.
Portions of Maine may see higher streamflows, which could affect populations of endangered Atlantic salmon. On the other hand, areas of the already drought-stressed Flint River Basin, one of Atlanta’s primary drinking water supplies, are projected to become even drier.
More USGS coverage here.
Routt County, et.al., are teaming with the USGS to monitor water quality in the upper Yampa River basinMarch 29, 2012
From Steamboat Today (Tom Ross):
Joining the county and Steamboat Springs in the local funding are the Upper Yampa Water Conservancy District, Mount Werner Water District and Morrison Creek Water and Sanitation District. Like the county, the city and the Conservancy District will contribute $9,071. Mount Werner Water and Morrison Creek Water each will contribute $2,268.
The new water-quality monitoring sites are in addition to the water-quality measuring site maintained by the Colorado Department of Health and Environment at the Fifth Street Bridge in downtown Steamboat since 2007. Now, samples at five sites will be tested for chemical content, nutrients, E. coli and alkalinity, among other properties…
[Routt County Environmental Health Director Mike Zopf] added that he expects to receive recommendations in the near future from the U.S. Geological Survey about a program to monitor water quality in aquifers in the valley, which could lead to monitoring groundwater quality, as well as surface-water quality.
Click here for the publication from the United States Geological Survey. Here’s an excerpt:
The most common method used by the USGS for mea- suring velocity is with a current meter. However, a variety of advanced equipment can also be used to sense stage and measure streamflow. In the simplest method, a current meter turns with the flow of the river or stream. The current meter is used to measure water velocity at predetermined points (sub- sections) along a marked line, suspended cableway, or bridge across a river or stream. The depth of the water is also measured at each point. These velocity and depth measurements are used to compute the total volume of water flowing past the line dur- ing a specific interval of time. Usually a river or stream will be measured at 25 to 30 regularly spaced locations across the river or stream.
Here’s the link to the USGS Water Watch website.
More USGS coverage here.
The United States Geological Survey was established on March 3, 1879, just a few hours before the mandatory close of the final session of the 45th Congress, when President Rutherford B. Hayes signed the bill appropriating money for sundry civil expenses of the Federal Government for the fiscal year beginning July 1, 1879. The sundry civil expenses bill included a brief section establishing a new agency, the United States Geological Survey, placing it in the Department of the Interior, and charging it with a unique combination of responsibilities: “classification of the public lands, and examination of the geological structure, mineral resources, and products of the national domain.” The legislation stemmed from a report of the National Academy of Sciences, which in June 1878 had been asked by Congress to provide a plan for surveying the Territories of the United States that would secure the best possible results at the least possible cost. Its roots, however, went far back into the Nation’s history.
The first duty enjoined upon the Geological Survey by the Congress, the classification of the public lands, originated in the Land Ordinance of 1785. The original public lands were the lands west of the Allegheny Mountains claimed by some of the colonies, which became a source of contention in writing the Articles of Confederation until 1781 when the States agreed to cede their western lands to Congress. The extent of the public lands was enormously increased by the Louisiana Purchase in 1803 and later territorial acquisitions.
At the beginning of Confederation, the decision was made not to hold the public lands as a capital asset, but to dispose of them for revenue and to encourage settlement. The Land Ordinance of 1785 provided the method of surveying and a plan for disposal of the lands, but also reserved “one-third part of all gold, silver, lead, and copper mines to be sold or otherwise disposed of, as Congress shall thereafter direct,” thus implicitly requiring classification of the lands into mineral and nonmineral. Mapping of the public lands was begun under the direction of the Surveyor-General, but no special provision was made for classification of the public lands, and it thus became the responsibility of the surveyor. There was,of course, no thought in 1785 or for many years thereafter of employing geologists to make the classification of the mineral lands, for geology was then only in its infancy.
More USGS coverage here.
Here’s the latest installment in their Water 2012 series from the Valley Courier. Click through and read the whole thing. Here’s an excerpt:
For the Rio Grande Compact, seven streamflow gaging stations are operated in the San Luis Valley to account for the water originating in the Conejos and Rio Grande systems and the water delivered from these systems to New Mexico. The Hydrographic Branch of the Colorado Division of Water Resources operates these seven gaging stations along with 73 other gaging stations across the San Luis Valley.
In addition to the Compact gages, stations are operated on natural streams and creeks to help water commissioners allocate the available water to water users, maintain a historic record of water in the stream, account for trans-mountain water brought into the basin, record water diverted at critical diversion structures, and provide valuable information to recreational enthusiasts such as kayakers and fishermen.
The data from these sites may be later used for water supply planning, flood warning, environmental studies, and basin modeling, such as the Rio Grande Decision Support System (RGDSS).
Meanwhile, USGS streamflow gages are facing funding cuts. Here’s a report from Bob Berwyn writing for the Summit County Citizens Voice. From the article:
…for years, ranchers, town planners and even angler and kayakers have relied on a huge network of streamflow gages maintained by the U.S. Geological Survey to help monitor water quality, measure and predict peak spring runoff and flooding potential, or even just the best time run some whitewater or to go fishing. In some places, the streamflow information is critical to helping protect endangered species.
But that network is shrinking, due mainly to budget constraints that already forced the USGS to shut down stations around the country. Just in the past few years, the agency stopped operating 133 water quality stations, many in New Mexico and Florida.
More Colorado Water 2012 coverage here.
Here’s the release from the United States Geological Service (Heidi Koontz):
A newly released U.S. Geological Survey study of decreasing groundwater resources in the Denver Basin aquifer provides information on water movement within the system and how it responds to changes in climatic and human activities.
The 3-D computer model of groundwater flow in the Denver Basin aquifer system was constructed to quantify and offer a “big picture” view of the hydrologic system. It will serve as a useful tool for analyzing past and present groundwater conditions, predicting future aquifer response to continued development, and guiding hydrologic monitoring and assessment in the Front Range urban corridor of Colorado.
The Denver Basin aquifer system is an essential water resource for growing municipal, industrial, and domestic uses. Continued population growth along the Front Range and the resulting increase in pumping for additional water supplies has resulted in water-level declines and storage depletion in the aquifer system.
“The Denver Basin aquifers are a critical, but declining, drinking water resource for tens of thousands of residents along the Front Range in Colorado,” said Anne Castle, Assistant Secretary for Water and Science at the U.S. Department of the Interior. “This model and the associated data sets are essential tools for local governments and water suppliers to achieve sustainable water supplies in the future.”
Developed by scientists at the USGS, the groundwater flow model will provide a better understanding about the effects of continued pumping and climate variability on groundwater availability and storage depletion in the Denver Basin. A professional paper detailing the Denver Basin groundwater flow model and study results, “Groundwater Availability of the Denver basin aquifer system, Colorado,” is available online.
“Many communities rely on groundwater resources for municipal, industrial, and agricultural water supplies, and yet unlike the situation with streams and reservoirs, citizens cannot readily assess for themselves whether they are unsustainably depleting this valuable resource,” said USGS Director Marcia McNutt. “Studies such as this by the USGS provide important information on the current status of the groundwater aquifer and its future potential so that communities can plan for their long-term water needs.”
To develop the model, scientists compiled information on aquifer geometry, aquifer properties, land use, pumping history, and climate from 1880 through 2003. Among their findings:
For predevelopment (pre-1880) conditions, recharge, or water entering the aquifer, from precipitation and agricultural irrigation return flows was the primary source of water (94 percent of inflow) to the Denver Basin bedrock aquifers, and evapotranspiration was the primary component of groundwater discharge from the bedrock aquifers (72 percent of outflow). Flow between the bedrock aquifers, the alluvial aquifer, and streams accounted for the remaining components of the predevelopment water budget.
Changes in land and water use have altered the groundwater flow system compared to predevelopment conditions. The expansion of urban/suburban land use and/or irrigated agriculture since the 1950s has increased water use on the landscape, which has increased recharge, evapotranspiration, and streamflow in connection with shallow parts of the aquifer system.
Groundwater pumping was estimated for the period 1880-2003 on the basis of permitted wells using previously published methods. About 55,000 permitted pumping wells were included in the analysis, of which about 44,000 wells were completed in the bedrock aquifers and about 8,000 wells were completed in the alluvial aquifer.
Groundwater pumping from the bedrock aquifers has increased steadily since the 1950’s, primarily in response to increased municipal water-supply needs, which has reduced natural discharge from the aquifer, lowered water levels in the bedrock aquifers, and removed water from aquifer storage.
The model developed by this study is a necessary tool for evaluation of groundwater resources in the Denver Basin. The results provide quantitative estimates of system changes through time consistent with a conceptual model of limited groundwater resources. However, ongoing monitoring and updates to the model are considered necessary for continued assessment of groundwater availability
The report was funded by the USGS Groundwater Resources Program, and information derived from this and future studies of more than 30 regional aquifers will provide a collective assessment of U.S. groundwater availability.
Here’s the abstract from the report:
The Denver Basin aquifer system is a critical water resource for growing municipal, industrial, and domestic uses along the semiarid Front Range urban corridor of Colorado. The confined bedrock aquifer system is located along the eastern edge of the Rocky Mountain Front Range where the mountains meet the Great Plains physiographic province. Continued population growth and the resulting need for additional water supplies in the Denver Basin and throughout the western United States emphasize the need to continually monitor and reassess the availability of groundwater resources.
In 2004, the U.S. Geological Survey initiated large-scale regional studies to provide updated groundwater-availability assessments of important principal aquifers across the United States, including the Denver Basin. This study of the Denver Basin aquifer system evaluates the hydrologic effects of continued pumping and documents an updated groundwater flow model useful for appraisal of hydrologic conditions.
The Fountain Creek Master Plan was the topic of discussion at Friday’s meeting of the Fountain Creek Watershed Flood Control and Greenway DistrictNovember 5, 2011
Here’s a in-depth report from Chris Woodka writing for The Pueblo Chieftain. Click through and read the whole article. Here’s an excerpt:
A corridor master plan Friday was combed over by the citizens advisory group to the Fountain Creek Watershed Flood Control and Greenway District board. The panel could not agree on whether a dam or series of dams is needed to protect projects that beautify the creek with trails and parks on Fountain Creek, a normally gentle stream prone to occasional violent floods. There also was no consensus on whether water quality should be improved before or after people are encouraged to enjoy the water…
The corridor plan addresses just the area in the flood plain between Pueblo and Colorado Springs, and is aimed at projects that will fit within the $50 million the district expects to receive five years from now. The district also needs to have projects that could convince voters to approve a mill levy when the time comes, said Larry Small, general manager of the district…
A dam on Fountain Creek could require moving railroad tracks and Interstate 25 or acquiring private land. A series of dams could be built on any of 21 tributaries along Fountain Creek and would be easier to clear as they periodically filled with sediment, Ready said. “You need a greenway so the creek can meander to slow down the water,” [Tom Ready, a Pueblo member of the committee] said. “You need to keep construction away from the creek. But no big dam will ever work.”[...]
[Larry Howe-Kerr of Better Pueblo] questioned the wisdom of drawing people to the creek if the water quality remains impaired. Small, Ready and others on the committee said the corridor plan does recommend actions that would improve water quality. They said recreation on the creek would get people to care about it, and does not necessarily mean coming in contact with the water…
The district is awaiting information from a U.S. Geological Survey study of the impact dams would have on Fountain Creek. In addition, Colorado Springs is developing a stormwater criteria manual which the district wants other communities to consider as well. It won’t be finalized until 2013. A white paper that looks at a comprehensive stormwater plan for El Paso County communities also is being drafted and should be presented to the district in the near future.
Meanwhile, two technical advisory committee meetings are on the horizon to discuss dam proposals and water rights issues on the creek, according to Chris Woodka writing for The Pueblo Chieftain. From the article:
The technical advisory committee of the Fountain Creek Watershed Flood Control and Greenway District will discuss the U.S. Geological Survey study of Fountain Creek dams at 10 a.m. Nov. 30 at the Pikes Peak Area Council of Governments office, 15 S. Seventh St., Colorado Springs.
The committee will have a panel discussion of water rights by experts from various organizations at 1 p.m. Dec. 7 at Fountain City Hall.
The USGS study is looking at the impacts of putting dams at various points along Fountain Creek to control floods. The study would not design or recommend dams, but is designed to measure the effectiveness of single projects or combinations of projects. The study is expected to be ready for review late next year and completed in 2013. The study is funded, in part, by $300,000 from Colorado Springs Utilities as a condition of the Pueblo County 1041 permit for the Southern Delivery System.
The water rights discussion is needed as the district and its partners develop demonstration projects for Fountain Creek, said Dennis Maroney, chairman of the technical committee.
USGS: Hydrogeologic Setting and Simulation of Groundwater Flow near the Canterbury and Leadville Mine Drainage Tunnels, Leadville, ColoradoOctober 16, 2011
Here’s the release from the U.S. Geological Survey (Wellman, T.P./Paschke, S.S./Minsley, Burke/Dupree, J.A.):
The Leadville mining district is historically one of the most heavily mined regions in the world producing large quantities of gold, silver, lead, zinc, copper, and manganese since the 1860s. A multidisciplinary investigation was conducted by the U.S. Geological Survey, in cooperation with the Colorado Department of Public Health and Environment, to characterize large-scale groundwater flow in a 13 square-kilometer region encompassing the Canterbury Tunnel and the Leadville Mine Drainage Tunnel near Leadville, Colorado. The primary objective of the investigation was to evaluate whether a substantial hydraulic connection is present between the Canterbury Tunnel and Leadville Mine Drainage Tunnel for current (2008) hydrologic conditions.
Altitude in the Leadville area ranges from about 3,018 m (9,900 ft) along the Arkansas River valley to about 4,270 m (14,000 ft) along the Continental Divide east of Leadville, and the high altitude of the area results in a moderate subpolar climate. Winter precipitation as snow was about three times greater than summer precipitation as rain, and in general, both winter and summer precipitation were greatest at higher altitudes. Winter and summer precipitation have increased since 2002 coinciding with the observed water-level rise near the Leadville Mine Drainage Tunnel that began in 2003. The weather patterns and hydrology exhibit strong seasonality with an annual cycle of cold winters with large snowfall, followed by spring snowmelt, runoff, and recharge (high-flow) conditions, and then base-flow (low-flow) conditions in the fall prior to the next winter. Groundwater occurs in the Paleozoic and Precambrian fractured-rock aquifers and in a Quaternary alluvial aquifer along the East Fork Arkansas River, and groundwater levels also exhibit seasonal, although delayed, patterns in response to the annual hydrologic cycle.
A three-dimensional digital representation of the extensively faulted bedrock was developed and a geophysical direct-current resistivity field survey was performed to evaluate the geologic structure of the study area. The results show that the Canterbury Tunnel is located in a downthrown structural block that is not in direct physical connection with the Leadville Mine Drainage Tunnel. The presence of this structural discontinuity implies there is no direct groundwater pathway between the tunnels along a laterally continuous bedrock unit.
Water-quality results for pH and major-ion concentrations near the Canterbury Tunnel showed that acid mine drainage has not affected groundwater quality. Stable-isotope ratios of hydrogen and oxygen in water indicate that snowmelt is the primary source of groundwater recharge. On the basis of chlorofluorocarbon and tritium concentrations and mixing ratios for groundwater samples, young groundwater (groundwater recharged after 1953) was indicated at well locations upgradient from and in a fault block separate from the Canterbury Tunnel. Samples from sites downgradient from the Canterbury Tunnel were mixtures of young and old (pre-1953) groundwater and likely represent snowmelt recharge mixed with older regional groundwater that discharges from the bedrock units to the Arkansas River valley. Discharge from the Canterbury Tunnel contained the greatest percentage of old (pre-1953) groundwater with a mixture of about 25 percent young water and about 75 percent old water.
A calibrated three-dimensional groundwater model representing high-flow conditions was used to evaluate large-scale flow characteristics of the groundwater and to assess whether a substantial hydraulic connection was present between the Canterbury Tunnel and Leadville Mine Drainage Tunnel. As simulated, the faults restrict local flow in many areas, but the fracture-damage zones adjacent to the faults allow groundwater to move along faults. Water-budget results indicate that groundwater flow across the lateral edges of the model controlled the majority of flow in and out of the aquifer (79 percent and 63 percent of the total water budget, respectively). The largest contributions to the water budget were groundwater entering from the upper reaches of the watershed and the hydrologic interaction of the groundwater with the East Fork Arkansas River. Potentiometric surface maps of the simulated model results were generated for depths of 50, 100, and 250 m. The surfaces revealed a positive trend in hydraulic head with land-surface altitude and evidence of increased control on fluid movement by the fault network structure at progressively greater depths in the aquifer.
Results of advective particle-tracking simulations indicate that the sets of simulated flow paths for the Canterbury Tunnel and the Leadville Mine Drainage Tunnel were mutually exclusive of one another, which also suggested that no major hydraulic connection was present between the tunnels. Particle-tracking simulations also revealed that although the fault network generally restricted groundwater movement locally, hydrologic conditions were such that groundwater did cross the fault network at many locations. This cross-fault movement indicates that the fault network controls regional groundwater flow to some degree but is not a complete barrier to flow. The cumulative distributions of adjusted age results for the watershed indicate that approximately 30 percent of the flow pathways transmit groundwater that was younger than 68 years old (post-1941) and that about 70 percent of the flow pathways transmit old groundwater. The particle-tracking results are consistent with the apparent ages and mixing ratios developed from the chlorofluorocarbon and tritium results. The model simulations also indicate that approximately 50 percent of the groundwater flowing through the study area was less than 200 years old and about 50 percent of the groundwater flowing through the study area is old water stored in low-permeability geologic units and fault blocks. As a final examination of model response, the conductance parameters of the Canterbury Tunnel and Leadville Mine Drainage Tunnel were manually adjusted from the calibrated values to determine if altering the flow discharge in one tunnel affects the hydraulic behavior in the other tunnel. The examination showed no substantial hydraulic connection.
The multidisciplinary investigation yielded an improved understanding of groundwater characteristics near the Canterbury Tunnel and the Leadville Mine Drainage Tunnel. Movement of groundwater between the Canterbury Tunnel and Leadville Mine Drainage Tunnel that was central to this investigation could not be evaluated with strong certainty owing to the structural complexity of the region, study simplifications, and the absence of observation data within the upper sections of the Canterbury Tunnel and between the Canterbury Tunnel and the Leadville Mine Drainage Tunnel. There was, however, collaborative agreement between all of the analyses performed during this investigation that a substantial hydraulic connection did not exist between the Canterbury Tunnel and the Leadville Mine Drainage Tunnel under natural flow conditions near the time of this investigation.
Here’s the link to the full report.
More Arkansas River basin coverage here.
Animas River watershed: Part two of series about the river, ‘Want water, take a number’ from The Durango HeraldAugust 29, 2011
Here’s Part Two of the four part series about the Animas River from Dale Rodebaugh and The Durango Herald. Mr. Rodebaugh outlines how uses of the river have changed over time, from prehistoric times to the filling of Lake Nighthorse (full on June 29 this year), part of the Animas-La Plata Project. Here’s an excerpt:
Durango’s early exploitation of the Animas was as a conduit to get logs to sawmills, where they were turned into lumber and railroad ties.
Today, most of the water pulledfrom the river is for irrigation and consumption, but the city of Durango in 2007 obtained a decree that guarantees a certain amount of flow for a whitewater park at Smelter Rapid. Several entities have won such rights for recreation since legislation establishing recreation rights was enacted in2001.
Also, a certain amount of water is reserved to protect two fish species in the San Juan River – the Colorado pikeminnow and humped-back chub,which are federally listed as endangered.
Click through for the whole article and the slide show.
Here’s a look at how the USGS measures streamflow, from Dale Rodebaugh writing for The Durango Herald. From the article:
The USGS maintains more than 7,000 gauging stations on rivers and lakes across the country. The Durango office manages 41 stations in La Plata, Archuleta, Montezuma, San Juan, Dolores, San Miguel, Ouray and Montrose counties.
The station near U.S. Highway 550 and 14th Street went into service in 1895, only six years after the first one ever was installed in New Mexico on the Rio Grande River to help determine whether there was sufficient water for irrigation.
The USGS computerized its gauging nationally in 1983 and first made real-time data available online in 1995.
Click through for the whole article and the video of hydrologic technician Jennifer Dansie at work on calibration chores.
Meanwhile, the Environmental Protection Agency is considering superfund status for parts of the upper Animas River watershed, according to Mark Esper writing for The Telluride Daily Planet. From the article:
And EPA officials said that while the collaborative approach to water quality in the upper Animas spearheaded by the Animas River Stakeholders Group has been successful, the worsening situation on Cement Creek has compelled the agency to study a possible Superfund listing.
“The problem is worsening water quality,” said Sabrina Forrest, site assessment manager for the EPA in Denver. Forrest explained that while the EPA considers the problem to be worthy of the National Priorities List (NPL) under the Superfund law, local support would be required as well as a sign-off from the governor.
“It’s eligible for listing, but community support is needed for that,” Forrest said. And if the Gladstone sites were to be eventually put on the NPL “the community would still have a huge voice on how this would be done.”[...]
Meanwhile, the EPA is planning a Sept. 16 site tour at Gladstone for those interested in getting a better idea of the situation on the ground up there. Forrest says the EPA hopes it can determine by Dec. 20 if there is enough local support for NPL listing to proceed. Under that timetable, the listing could be made official by March 2012.
The preliminary assessment work focused on a cluster of mine sites at and above Gladstone, including the American Tunnel, Gold King Number 7 level, the Mogul and Grand Mogul and the Red and Bonita mines. Peter Butler of Durango, a steering committee member for the Animas River Stakeholders Group, which was formed as a collaborative approach to water quality issues in 1994, said Cement Creek has seen a steady increase in metals loading since a treatment plant at Gladstone was shut down in 2004. Up to 845 gallons per minute of acid mine drainage is pouring into Cement Creek from just four abandoned mines above Gladstone…
At this point, Butler said possible solutions include various scenarios for a water treatment plant on Cement Creek, bulkheads for the four mines discharging the most, or some combination of that. Then comes the question of who pays. Butler said options include seeking damages from Sunnyside Gold’s parent company, Kinross; luring a large mining company to reopen the Gold King and take on the cleanup liability; taking an incremental approach with a pilot treatment project that could be expanded; invoking Superfund; or a combination thereof.
Todd Hennis of Golden, who described himself as the “unfortunate owner of the Gold King and Mogul mines,” said the EPA has been spinning “fairy tales.” “The problem started in 2000 when water started coming out of the Mogul,” Hennis said. He said that was a result of the American Tunnel bulkheads causing water to back up. The water table has since risen an estimated 1,000 feet, causing acid mine drainage to seep from ever higher points on the mountain. Hennis accused state officials of engaging in “pollution trading” with Sunnyside Gold, with a consent decree letting the mining firm off the hook for water quality problems in the Gladstone area. “The state of Colorado has a huge responsibility for this situation,” Hennis said. “Sunnyside walked out of this district and their $5 million bond was returned.” Hennis said the best solution would be for a mining firm to reopen the Gold King and assume responsibility for the water quality issues. Hennis said he thinks there is $700 million in gold still retrievable from the Gold King mine.
Here’s an article that details the course of the Animas River, including the geology, from its headwaters to the San Juan River, from Dale Rodebaugh writing for The Durango Herald. Here’s an excerpt:
At one time, [David Gonzales, a professor and chairman of the geosciences department at Fort Lewis College] said, gravel impelled by a glacier created a dam to form a lake in the Animas Valley. Later erosion of the debris drained the lake but caused the relatively flat and wide channel. The farthest reaching glacier, which receded about 12,000 years ago, carried gravel as far as 32nd Street, Gonzales said.
More Animas River watershed coverage here.
USGS Study Finds Recent Snowpack Declines in the Rocky Mountains Unusual Compared to Past Few CenturiesJune 13, 2011
From the Loveland Connection (Bobby Magill):
Using tree ring samples to reconstruct the size of mountain snowpack over the past millennium, USGS researchers were able to show that reductions in the size of the mountain snowpack across the West during the past 30 years is unusual when considering the size of the mountain snowpack each year during the past three centuries…
There was an “inflection point” in the 1980s when the size of a given year’s snowpack was more influenced by temperature than by amount of precipitation, said USGS research scientist Gregory Pederson, lead author of the study, “The Unusual Nature of Recent Snowpack Declines in the North American Cordillera.”[...]
“The region you are sitting in is a particularly dynamic one,” he said. “These basins haven’t shown the substantial temperature-driven declines since the 1980s. (Colorado’s northern mountains) seem fairly resistant to fairly extensive snowpack decline like you see across the Northern Rockies.”
USGS Study Finds Recent Snowpack Declines in the Rocky Mountains Unusual Compared to Past Few CenturiesJune 11, 2011
From The Colorado Springs Gazette (R. Scott Rappold):
Researchers examined tree rings to look at moisture trends going back 500 to 1,000 years, in the first study to examine historic snowpack in this manner. While the northern Rockies have seen the most dramatic loss – less snow, earlier melt-offs – the southern Rockies, including Colorado, have experienced similar trends since the 1980s. That bucks the historical trend, that when the northern Rockies have more snow, the south has less, and vice versa. The recent drops are across the board, 30 to 60 percent of the snowpack.
The study comes at a time of heavy lingering snowpack in Colorado, 248 percent of the average for mid-June. But, said lead author Gregory Pederson, the average is based on recent years; the long view shows this winter may not be as out-of-whack as it seems. “There’s nothing unusual per se about this year, just that it comes in the midst of a lot of low-snowpack years,” he said.
He said the study, along with other research that has shown Western snowpack declines, should be a warning for water suppliers. The only similar periods occurred in the 1350s and 1400s, he said, and these were followed by colder, snowier eras. But, because of the impact of greenhouse gasses, Pederson does not believe that will occur again. “With increased warming, we may now be seeing this temperature impact on the snowpack, more of the precipitation falling as rain rather than snow,” he said…
[Colorado Springs Utilities Water supply planning supervisor Abby Ortega] said the fact the city’s water comes from three different basins insulates it from some of the problems of erratic snowpack. This year, for example, the Arkansas basin has less than half the snowpack of the other side of the Continental Divide, and Pikes Peak has been exceptionally dry.
More coverage from Dan Vergano Sci-Tech Today. From the article:
The historical snowpack reconstruction results, dating to the year 1200 and released by the journal Science, suggest that global warming has broken the normal seesaw pattern of snowpack in the region, in which a down year in the northern Rockies will be offset by a higher snow year in the southern Rockies. Overall, the average yearly snowpack across the northern Rockies directly known from snow records to have dropped 30% to 60% in the past 50 years has fallen more sharply in that time than for any period in the past 800 years, the study shows. “Temperature is the driver here,” says study lead author Greg Pederson of the U.S. Geological Survey’s Northern Rocky Mountain Science Center in Bozeman, Mont. “It doesn’t take a rocket scientist to know that if temperatures get warmer, snow and ice melt sooner.”[...]
The Northern Rockies stretch from Washington state to Montana. The study records show two-decade-long drops in snowpack across the northern Rockies in the 1300s and 1500s that resemble the decline seen in the 20th century, but those declines lasted for shorter periods of time and came when far fewer people were dependent on the snowpack. “Water demand, as much as supply, is the problem,” Pederson says. “We have a lot of fisheries and hydropower relying on this water as well.”
More Colorado River basin coverage here.
USGS Study Finds Recent Snowpack Declines in the Rocky Mountains Unusual Compared to Past Few CenturiesJune 10, 2011
Here’s the release from the United States Geological Survey:
A USGS study released today suggests that snowpack declines in the Rocky Mountains over the last 30 years are unusual compared to the past few centuries. Prior studies by the USGS and other institutions attribute the decline to unusual springtime warming, more precipitation falling now as rain rather than snow and earlier snowmelt.
The warming and snowpack decline are projected to worsen through the 21st century, foreshadowing a strain on water supplies. Runoff from winter snowpack – layers of snow that accumulate at high altitude – accounts for 60 to 80 percent of the annual water supply for more than 70 million people living in the western United States.
“This scientific work is critical to understanding how climate change is affecting western water supplies,” Secretary of the Interior Ken Salazar said. “It helps land managers adapt to changing conditions on the ground, assists water managers with planning for the future, and gives all of us a better understanding of the real impacts that carbon pollution is having on our resources and our way of life.”
USGS scientists, with partners at the Universities of Arizona, Washington, Wyoming, and Western Ontario, led the study that evaluated the recent declines using snowpack reconstructions from 66 tree-ring chronologies, looking back 500 to more than 1,000 years. The network of sites was chosen strategically to characterize the range of natural snowpack variability over the long term, and from north to south in the Rocky Mountains.
With a few exceptions (the mid-14th and early 15th centuries), the snowpack reconstructions show that the northern Rocky Mountains experience large snowpacks when the southern Rockies experience meager ones, and vice versa. Since the 1980s, however, there were simultaneous declines along the entire length of the Rocky Mountains, and unusually severe declines in the north.
“Over most of the 20th century, and especially since the 1980s, the northern Rockies have borne the brunt of the snowpack losses,” said USGS scientist Gregory Pederson, the lead author of the study. “Most of the land and snow in the northern Rockies sits at lower and warmer elevations than the southern Rockies, making the snowpack more sensitive to seemingly small increases in temperature. Also, winter storm tracks were displaced to the south in the early 20th century and post-1980s. Forest fires were larger, more frequent and harder to fight, while Glacier National Park lost 125 of its 150 glaciers.”
USGS scientist and co-author Julio Betancourt explains that “The difference in snowpack along the north and south changed in the 1980s, as the unprecedented warming in the springtime began to overwhelm the precipitation effect, causing snowpack to decline simultaneously in the north and south. Throughout the West, springtime tends to be warmer during El Niño than La Niña years, but the warming prior to the 1980s was usually not enough to offset the strong influence of precipitation on snowpack.”
The La Niña episode this year is an example with lots of snow in the north while severe drought afflicts the south. But, in the north, this year’s gains are only a small blip on a century-long snowpack decline.
In the West, the average position of the winter storm tracks tend to fluctuate north and south around a latitudinal line connecting Denver, Salt Lake City and Sacramento. In El Niño years, winter storms track south of that line, while in La Niña years, they track to the north.
This study supports research by others estimating that between 30-60 percent of the declines in the late 20th century are likely due to greenhouse gas emissions. The remaining part of the trend can be attributed to natural decadal variability in the ocean and atmosphere, which is making springtime temperatures that much warmer.
“What we have seen in the last few decades may signal a fundamental shift from precipitation to temperature as the dominant influence on western snowpack.” Pederson said.
The study, The unusual nature of recent snowpack declines in the North American Cordillera, is online at Science magazine http://www.sciencemag.org/lookup/doi/10.1126/science.1201570.
More coverage from Chris Woodka writing for The Pueblo Chieftain. From the article:
USGS scientists, with partners at the universities of Arizona, Washington, Wyoming, and Western Ontario, led the study that evaluated the recent declines using snowpack reconstructions from 66 tree-ring chronologies, looking back 500-1,000 years. With a few exceptions (the mid-14th and early 15th centuries), snowpack reconstructions show that the northern Rocky Mountains experience large snowpacks when the southern Rockies experience meager ones, and vice versa. Since the 1980s, however, there were simultaneous declines along the entire length of the Rocky Mountains, and unusually severe declines in the north.
More coverage from Felicity Barringer writing for The New York Times weblog Green. From the post:
On the one hand, the underlying narrative was depressingly familiar, synchronizing with other studies or predictions involving California’s Sierra, the Himalayas and other spots around the world. What drew my attention is the reminder that snowmelt in the Rockies feeds three huge river systems — the Colorado, the Columbia and the Missouri — on which 70 million Americans depend for water.
Not that everyone living along — or flooded out of the communities along — the Missouri River or its swollen tributaries would consider these findings intuitive. But the U.S.G.S. scientists who led the study point out that climate in the Rocky Mountains has for centuries been an either-or proposition.
It works like this. Draw a hypothetical line in your mind from Denver to Salt Lake City to Sacramento. If there is heavy snow to the north of this line, chances are there will be a drought to the south of it. And vice versa. Or, as an Interior Department press release said, “With a few exceptions (the mid-14th and early 15th centuries), the snowpack reconstructions show that the northern Rocky Mountains experience large snowpacks when the southern Rockies experience meager ones, and vice versa.”
More coverage from United Press International. From the article:
The study backs research that the USGS said estimates that as much as 60 percent of the snowpack declines in the late 20th century are because of greenhouse gas emissions, which are linked to higher global temperature averages…Runoff from winter snowpack makes up nearly 60 percent of the annual water supply for people in the western United States.
More coverage from Craig Welch writing for The Seattle Times via the Bend Bulletin. From the article:
Pederson and his colleagues say the findings are important because they suggest the mountain snows that produce the runoff that powers the Columbia, the Missouri and the Colorado river systems will continue to decline as global temperatures rise, even if precipitation increases.
More coverage from Margaret Munro writing for The Vancouver Sun. From the article:
The study, published Thursday in the journal Science, says the changes are affecting the Colorado, Columbia and Missouri Rivers, which together supply water to 70 million Americans. And they are also altering river flows in the Canadian prairies and central British Columbia, said co-author Brian Luckman, at the University of Western Ontario.
“Snowpack is essential for water supply to many of these areas,” Luckman said, noting that the Rockies feed rivers flowing through central B.C. and the Bow, Athabasca and Oldman rivers in Alberta. “Between 60 to 80 per cent of the water in those rivers is snowmelt from the mountains.”
Mountain snow records don’t go back far beyond 1950, so the team, led by Gregory Pederson at the U.S. Geological Survey, looked at tree rings at 66 sites from B.C. to Colorado to get a read on snowpack levels over the past 800 years.
They found that the snowpack shrank more during the late 20th century than during any other period since 1200 AD, with more severe declines at the northern end of the range studied.
Luckman says the tree rings track the depth of the snowpack because some species such as the alpine larch tend not to grow well in heavy snowpack years because it takes so long for water to start flowing on mountaintops. Trees like Ponderosa Pines at lower elevations thrive in years of heavy snowpack, resulting in thicker tree rings.
More coverage from Joey Bunch writing for The Denver Post. From the article:
The dire long-term forecast cites warmer springs, earlier snowmelts and shifting winter storm patterns, all possible byproducts of global warming caused by greenhouse-gas emissions, according to the USGS. While that could prove disastrous for Colorado’s ski and rafting industries, it’s too early to say if it means less water overall, said Marc Waage, the manager of water-resources planning for Denver Water, which supplies 1.3 million people in the metro region. “I don’t think from this study you can conclude that the overall amount of water is going to decline,” he said, “because we could be compensating snowpack with rain.”
More USGS coverage here.
I’ve been watching Clear Creek at Golden and the Cache la Poudre at Fort Collins via the text message service, USGS Water Alert. You choose a threshold for either gage height or flow in cubic feet per second along with a frequency for notification. Notification is via text message or email.
The USGS also runs an online application Water Watch. If you select by state, say Colorado, you can mouse over your favorite gage and read the current stats. The application shows a graphical representation of all reporting gages across the state as well.
Click on the thumbnail graphic above and to the right for a screen shot from this morning. The dots represent current streamflow as compared to average at the location. The legend is at the bottom.
Update: The state website is now back up.
The state’s website is not responding this morning so I’ll point you to it when the link will work.
Wow, Flood DSS is also down. That can’t be good if you’re depending on it for information to use for flood response or emergency response this weekend.
The outage is widespread. The governor’s and state legislature’s websites are not reachable .
USGS: Well Installation, Single-Well Testing, and Particle-Size Analysis for Selected Sites in and near the Lost Creek Designated Ground Water Basin, North-Central Colorado, 2003–2004April 5, 2011
Here’s the release from the USGS:
This report describes results from a groundwater data-collection program completed in 2003–2004 by the U.S. Geological Survey in support of the South Platte Decision Support System and in cooperation with the Colorado Water Conservation Board. Two monitoring wells were installed adjacent to existing water-table monitoring wells. These wells were installed as well pairs with existing wells to characterize the hydraulic properties of the alluvial aquifer and shallow Denver Formation sandstone aquifer in and near the Lost Creek Designated Ground Water Basin. Single-well tests were performed in the 2 newly installed wells and 12 selected existing monitoring wells. Sediment particle size was analyzed for samples collected from the screened interval depths of each of the 14 wells.
Hydraulic-conductivity and transmissivity values were calculated after the completion of single-well tests on each of the selected wells. Recovering water-level data from the single-well tests were analyzed using the Bouwer and Rice method because test data most closely resembled those obtained from traditional slug tests. Results from the single-well test analyses for the alluvial aquifer indicate a median hydraulic-conductivity value of 3.8 x 10-5 feet per second and geometric mean hydraulic-conductivity value of 3.4 x 10-5 feet per second. Median and geometric mean transmissivity values in the alluvial aquifer were 8.6 x 10-4 feet squared per second and 4.9 x 10-4 feet squared per second, respectively. Single-well test results for the shallow Denver Formation sandstone aquifer indicate a median hydraulic-conductivity value of 5.4 x 10-6 feet per second and geometric mean value of 4.9 x 10-6 feet per second. Median and geometric mean transmissivity values for the shallow Denver Formation sandstone aquifer were 4.0 x 10-5 feet squared per second and 5.9 x 10-5 feet squared per second, respectively. Hydraulic-conductivity values for the alluvial aquifer in and near the Lost Creek Designated Ground Water Basin generally were greater than hydraulic-conductivity values for the Denver Formation sandstone aquifer and less than hydraulic-conductivity values for the alluvial aquifer along the main stem of the South Platte River Basin reported by previous studies.
Particle sizes were analyzed for a total of 14 samples of material representative of the screened interval in each of the 14 wells tested in this study. Of the 14 samples collected, 8 samples represent the alluvial aquifer and 6 samples represent the Denver Formation sandstone aquifer in and near the Lost Creek Designated Ground Water Basin. The sampled alluvial aquifer material generally contained a greater percentage of large particles (larger than 0.5 mm) than the sampled sandstone aquifer material. Alternatively, the sampled sandstone aquifer material generally contained a greater percentage of fine particles (smaller than 0.5 mm) than the sampled alluvial aquifer material consistent with the finding that the alluvial aquifer is more conductive than the sandstone aquifer in the vicinity of the Lost Creek Designated Ground Water Basin…
Beck, J.A., Paschke, S.S., and Arnold, L.R., 2011, Well installation, single-well testing, and particle-size analysis for selected sites in and near the Lost Creek Designated Ground Water Basin, north-central Colorado, 2003–2004: U.S. Geological Survey Open-File Report 2011–1024, 23 p.
USGS: Simulation of Hydraulic Conditions and Observed and Potential Geomorphic Changes in a Reconfigured Reach of Muddy Creek, North-Central Colorado, 2001–2008March 5, 2011
Muddy Creek near Kremmling, Colorado, is a regulated, meandering, gravel-bed stream that has been monitored for geomorphic change since 2001. One reach of the creek was reconfigured using natural-channel design methods in 2003, providing an opportunity to compare hydraulics in this reach with those in a nearby, unaltered control reach. Streamflow in Muddy Creek has been regulated by Wolford Mountain Reservoir since 1995, but reservoir releases in 2006 and 2008 resulted in out-of-bank floods. The Muddy Creek monitoring program was conducted by the U.S. Geological Survey from 2001 to 2008 in cooperation with the Colorado River Water Conservation District, and the streamflow modeling and analysis were conducted in 2008 in cooperation with the Colorado River Water Conservation District and the Colorado Water Conservation Board.
Minor changes in channel geometry were measured at monitored cross sections in the control reach between 2001 and 2008 and in the reconfigured reach between 2003 and 2008. Geomorphic changes were limited to lateral erosion in a meander bend and lateral erosion of an alluvial fan that formed a vertical scarp in the control reach. Some excavated streambed locations in the reconfigured reach have aggraded to their former elevations, and gravel on alluvial bars might have become better sorted and winnowed of sand-size sediment. Hydraulic conditions in the reconfigured and control reaches were simulated using the U.S. Geological Survey MD_SWMS framework and FaSTMECH computational models.
Elliott, J.G., Schaffrath, K.R., McDonald, R.R., Williams, C.A., and Davis, K.C., 2011, Simulation of hydraulic conditions and observed and potential geomorphic changes in a reconfigured reach of Muddy Creek, north-central Colorado, 2001–2008: U.S. Geological Survey Scientific Investigations Report 2010–5183, 43 p.
More Colorado River basin coverage here.