Aspen utilities official favors new dams on local streams — Aspen Journalism

March 15, 2015
Gravity dam

Gravity dam

From Aspen Journalism (Brent Gardner-Smith):

A top utility official with the city of Aspen voiced his support last week for building “small reservoirs” on a number of streams in the Roaring Fork River watershed, including on Hunter, Castle, Maroon, and Avalanche creeks.

“Small reservoirs would improve stream flow on tributaries,” said Mike McDill, deputy director of utilities for the city of Aspen, referring to the ability to store water in the spring and release it later during low-flow periods.

“A small reservoir on Castle Creek would improve the stream health on Castle Creek and also help our drinking water reserves,” McDill said. “I think there may also be benefits to Hunter Creek, Maroon Creek and maybe even Avalanche Creek. All of our tributaries could use that kind of small reservoir and stream-flow calming.”

Today, the city of Aspen owns two diversion dams, one on lower Castle Creek next to Dick Butera’s estate, and one on lower Maroon Creek near the T-Lazy Ranch. Both of the dams are river wide and completely block fish passage, but they do not form reservoirs of water behind them.

McDill also said the city fully intends to keep its options open for two large dams on both upper Castle and Maroon creeks, which he referred to as “serious water storage reservoirs.”

McDill’s remarks were made during a public meeting of the Roaring Fork Watershed Collaborative, held at the Third Street Center in Carbondale.

At the watershed meeting, consulting engineers from SGM were facilitating a group-planning exercise in an effort to determine the top three water projects in the Roaring Fork River basin for inclusion in the forthcoming statewide Colorado Water Plan.

The effort did not result in a definitive shortlist of water projects, and no one else at the meeting spoke in favor of Aspen building new dams.

The Colorado River Basin Roundtable is slated to finalize a water project list for the entire Colorado River basin March 23.

“Serious water reservoirs”

McDill represents the city of Aspen on the Colorado Roundtable, and over the past year has consistently said the city needs to develop or acquire water storage.

“The city of Aspen, most of the cities in the region, none of them have any storage,” McDill said. “Their storage is snowpack, as is ours. I can tell you that that works great in the spring, works great through the summer. But believe it or not, our times of greatest concern are January, February, March, because Castle Creek, where we take most of water, is so low that we have to send a crew out almost every morning to chip the ice off of our intake bars, because the development of an inch or so of ice is enough to block our intake.”

McDill said the city, in addition to exploring new storage options, also is developing new water-supply projects, such as a reclaimed-water system and a deep-water well originally drilled as part of a geothermal energy project.

“The reason that we are doing that and the reclaimed water system,” McDill said, “is they are all really part of this idea of continuing due diligence to try to investigate every other possible way to provide the security for our drinking water system before we go to the point of building serious water storage reservoirs.

“We have reservoir storage rights on Maroon Creek and Castle Creek,” McDill added. “We know that’s going to be a really hard sell whenever we would start to do that, so before we even try, we’re going to look at every other alternative.”

The city holds conditional water rights for dams and reservoirs on both upper Castle and Maroon creeks.

The Maroon Creek reservoir would store 4,567 acre-feet of water behind a 155-foot-tall dam just below the confluence of East Maroon and West Maroon creeks, about a mile-and-half from Maroon Lake.

The Castle Creek reservoir would hold 9,062 acre-feet of water behind a 170-foot-tall dam located about two miles below the historic town site of Ashcroft.

The city’s conditional water rights for the Castle and Maroon creek reservoirs are officially on the state’s books through 2016, when the city will need to convince the state water court it is diligently making progress toward building the dams.

(Please see related stories: “Aspen’s Ruedi water buy may bolster prospect for new dams on Castle and Maroon creeks” and “City maintains rights for dams on Castle and Maroon creeks“)

Small and large reservoirs

When McDill was asked at Thursday’s meeting what his definition of a “small dam” is, he pointed to the city’s Leonard Thomas Reservoir at the city’s water treatment plant, which he said holds 14 acre feet of water. The dam at the reservoir is 19 feet tall.

“But it’s a good question,” McDill then said. “What’s a large reservoir?”

He went on to say that the conditional water rights for the Maroon and Castle creek reservoirs were “in the neighborhood of 10,000 acre-feet,” and that the other “smaller” reservoirs under discussion were in the “4,000 to 5,000 to 6,000” acre-foot range.

Editor’s note: Aspen Journalism is collaborating with The Aspen Times on coverage of rivers and waters. The Times published this story on Friday, March 13, 2015.

More Roaring Fork River watershed coverage here.


On Monday the City of Aspen officially ended its pursuit of a hydroelectric generation plant on Castle Creek — Aspen Journalism

February 25, 2015


The City of Aspen councilors decide to let FERC hydropower application expire in March

January 28, 2015


From The Aspen Times (Karl Herchenroeder):

The Federal Energy Regulatory Commission granted Aspen its first three-year preliminary permit for a 1,175-kilowatt hydropower plant on lower Castle Creek in November 2008 and a second three-year permit in March 2012.

City Attorney Jim True recommended allowing the permit to expire on March 1, which would officially put the controversial Castle Creek Energy Center on ice, for now. City officials did, however, agree to continue exploring micro-hydro projects on Castle and Maroon creeks, which True said would involve protection of city water rights.

“We will update you on those issues,” True told the council, adding that there will be more detailed analysis later. “We do believe there are additional protections.”

Will Dolan, the city’s utilities project coordinator, said that if the city were able to install low-head hydro on Maroon Creek, it would allow it to run more water through the existing Maroon Creek hydroplant and “optimize production.” Councilwoman Ann Mullins asked if it will affect streamflows.

“It wouldn’t affect the flow regimes necessarily,” Dolan said. “It would allow us to more fully utilize our water rights, but it wouldn’t create any additional diversion from the stream.”

“These are issues we want to bring back in greater detail,” True said, adding that consultation with federal and city water attorneys is needed.

Councilman Adam Frisch said he believes there is broad community support to explore micro-hydro and called the plan that True laid out “a great step forward.” None of the council members offered objections to True’s recommendation.

“I agree to let it expire, continue the investigation of micro-hydro and have a universal statement on protecting water rights,” Councilman Dwayne Romero said.

In March, the city filed a progress report saying it was still working on the Castle Creek project, despite a November 2012 advisory vote where 51 percent of city voters said the city should stop doing so.

However, in June, the city settled a lawsuit over its water rights for the proposed hydroplant. Both the settlement and a subsequent city council resolution said the city “will not be pursuing or seeking to complete the Castle Creek Energy Center hydroelectric project at this time.”

More hydroelectric/hydropower coverage here and here.


Aspen faces deadlines on federal hydro permit — Aspen Journalism

January 8, 2015
Aspen

Aspen

From Aspen Journalism (Brent Gardner-Smith) via The Aspen Times:

The Aspen City Council is expected Jan. 12 to face decisions about its federal permit for a hydropower plant on Castle Creek, as the permit expires Feb. 28 and there are deadlines Jan. 29 and March 1 if the city wants to keep the permit alive.

The Federal Energy Regulatory Commission granted Aspen its first three-year preliminary permit for a 1,175-kilowatt hydropower plant on lower Castle Creek in November 2008, and its second three-year permit in March 2012.

In the past nine months, the city’s communication with the commission has signaled varying degrees of commitment for the project.

In March, the city filed a progress report saying it was still working on the project, despite a November 2012 advisory vote where 51 percent of city voters said the city should stop doing so.

“The Aspen City Council has not abandoned the project … ” the city told the agency in March. “The project remains a viable project at this juncture, one which the city continues to study and to defend the water rights upon which its plans are based.”

In June, however, the city settled a lawsuit over its water rights for the proposed hydropower plant. Both the settlement and a subsequent City Council resolution said the city “will not be pursuing or seeking to complete the Castle Creek Energy Center hydroelectric project at this time.”

Instead, the city declared it was going to “pursue other renewable energy projects, including microhydroelectic installations at existing city-owned or controlled facilities.”

Those facilities are two diversion dams located several miles up Castle and Maroon creeks, which are currently used to divert water to the city’s water treatment plant.

The city in June sent FERC a copy of the resolution and the settlement agreement, and feels it gave adequate notice to the commission that its position on the project had evolved to embrace microhydro, Aspen City Attorney Jim True said.

But in September, the city sent FERC a progress report that seemed to suggest the city was leaving the door open for the plant on lower Castle Creek.

“In the event the City Council decides to proceed with the Castle Creek Energy Center project as a chosen alternative, the city will move forward as appropriate in accordance with applicable statues and regulations,” the city stated.

On Dec. 23, True said that sentence should not be taken to mean the city is still pursuing the original project.

Micro-hydroelectric plant

Micro-hydroelectric plant

“The city intends to pursue microhydro and we’ve made that clear to FERC,” True said. “We’re not looking at the Castle Creek Energy Center any more, at all.”

But if the city is not pursuing the lower Castle Creek project and instead plans to study microhydro projects, should it ask FERC to extend or renew its existing preliminary permit?

That’s one question the City Council is facing Jan. 12.

The city does have the right to apply for a third “successive” preliminary permit, but Shana Murray, who manages hydro projects at FERC, said it would be difficult.

“We will take a very hard look at what they have done to develop a license application over the last six years.”

Karl Kumli, an attorney working for the city on its federal permit, was more upbeat about the chances of extending the city’s current permit, even though the city’s focus has shifted.

“A preliminary permit, by its very nature, has some flexibility associated with it because you are studying options,” Kumli said.

Murray said if Aspen did want to file for a third permit, it would be expected to do so on March 1, the day after its current permit expires Feb. 28.

That is because one purpose of a preliminary permit is to secure the location of a proposed hydropower plant, so most applicants don’t leave a gap of even one day.

The city also has the option, with the passage of the federal Hydropower Regulatory Efficiency Act of 2013, to apply for a two-year extension to its current permit.

Murray said so far two-year extensions on second permits are getting about the same level of scrutiny at FERC as applications for a third permit.

However, if the city wants to go that route, it would need to notify FERC officials 30 days before the existing permit expires Feb. 28, which in this case is Jan. 29.

Murray wouldn’t speculate on how the agency would respond if the city applies to extend or renew its permit.

The city also has the option of simply letting its current permit expire and then applying for a new permit, or permits, for its proposed microhydro projects.

And in June, the city signaled to FERC it might go that route, although it did not discuss letting its current permit expire.

“In the near future, the city anticipates filing a separate preliminary permit or permits for such microhydro sites, which will be separate and different projects from the Castle Creek Energy Center,” the city said in its update.

Aspen Journalism and The Aspen Times are collaborating on coverage of rivers and water. More at http://www.aspenjournalism.org.

More hydroelectric/hydropower coverage here.


Aspen puts the skids under proposed hydroelectric plant — council pulls funding for penstock

November 27, 2014
Micro-hydroelectric plant

Micro-hydroelectric plant

From the Aspen Times (Karl Herchenroeder):

The Aspen City Council reversed its decision to spend $750,000 on an emergency drainline associated with the controversial Castle Creek Energy Center on [November 9] after city staff admitted mistakes in communicating the issue to officials and the public.

To date, the city has invested about $7 million in the estimated $10.5 million hydro project, which was halted in 2012 when 51 percent of Aspen voters shot it down during an advisory election. The 3,900-foot drainline, which was originally intended to source the hydroelectric plant with water from Thomas Reservoir, is about 91 percent complete but is currently capped and inoperable.

On May 27, the Colorado Department of Natural Resources conducted a scheduled inspection, which found the reservoir to be a “significant hazard,” meaning damage is expected with a dam failure while the reservoir is at the high-water line. Aspen’s Utilities Manager Dave Hornbacher admitted Monday that he misrepresented the issue to the council in October, when he gave officials the impression that it was a safety issue and state recommendations called for the drainline.

“Clearly, I could have done a better job, and I sincerely apologize for any misunderstanding or confusion or lack of diligence,” Hornbacher said.

Hornbacher explained that staff presented its recommendation as if it were based solely on the dam inspection, when in fact, officials also considered opportunities to address the potential for property damage near the drainline.

Assistant City Manager Randy Ready, who also admitted mistakes in his delivery to the council, made the case that staff was blinded by the opportunity to address two issues at once. He said that a question from the council that staff failed to respond to was, “How do we minimally meet the dam inspector’s requirements?”

More background from Brent Gardner-Smith writing for Aspen Journalism:

David Hornbacher, the city of Aspen’s director of utilities, acknowledged Friday he may have oversold the impact of a May 27 state dam safety report to the city council on Oct. 21, when he successfully convinced elected officials at a budget work session to approve $750,000 to complete the tail end of a big pipeline running from the bottom of Leonard Thomas Reservoir toward Castle Creek.

Hornbacher left the council with the distinct impression that the state was now requiring the city to complete the pipeline, originally envisioned as a penstock to a proposed hydropower plant, and now primarily seen as an “emergency drain line” for the city reservoir.

But, as it turns out, the state is not specifically requiring the city to finish its big pipeline, nor has it ever told the city the pipeline is required to safely operate the reservoir.

Erin Gleason is the state dam safety engineer with the Colorado Division of Water Resources who inspected the dam and reservoir in May. She wants documentation that the city can slowly draw down the reservoir through its existing low level outlet, which today directly feeds the city’s adjoining water treatment plant, or whether a bypass of the plant will be required.

“It might just be that I need information,” Gleason said.

After talking with Gleason on Friday, Hornbacher said he now intends to research whether the city can meet Gleason’s concerns by either using the reservoir’s current low-level outlet system, or if it can do so after some level of modification. He said he would prepare a range of options that compare cost and risk and bring them to council to discuss.

Hornbacher also said he would clarify things by describing two types of potential emergencies at the reservoir. The first is some type of structural threat to the dam, which would require the use of a low-level outlet to slowly draw down the reservoir. The proposed emergency drain line, if finished, would serve as a low-level outlet.

The second type is a a hydrologic event, such as losing control of the two feeder pipes that can bring up to 52 cfs of water to the reservoir, which requires the use of a spillway or an emergency drain line to deal with more water coming into the reservoir than it has the capacity to contain.

“We look forward to having a greater depth of discussion to solutions to a low-level outlet and a hydrologic event, and we look forward to a follow-up to have a detailed discussion about the options,” Hornbacher said.

Hornbacher said on Friday that he did not try to mislead the city council about the reservoir.

“My intent is to try and be factual and accurate and convey the information in an open and honest way,” Hornbacher said, pointing out that his answers were to questions at a budget work session, and he did not make a formal proposal.

And it’s fair to note that it is Hornbacher’s standing professional opinion that the city should complete the last 360 feet of the 4,000-foot-long pipeline installed before the proposed hydropower project ran into political turmoil and was mostly shelved by the city council.

He has consistently pointed out that the pipeline is a better way to move a lot of water out the reservoir than running it down the hillside just to the east of the reservoir. However, the city does routinely run 3 to 4 cubic feet per second (cfs) of water down the hillside toward the creek, but Hornbacher is concerned that a flow of 52 cfs could damage Castle Creek Road.

A water tight case?

At an Oct. 21 budget work session, Hornbacher was asked by council to answer questions about the $750,000 line item in the 2015 budget. (On meeting video, start at 26:52).

There was no staff memo on the topic and the May 27 dam inspector’s report was not in the public packet, nor was the last inspector’s report from April 2012.

However, the discussion turned toward the May report from Gleason.

“The report requires that we complete, or provide some level of a low-level drain line, or outlet, to this reservoir,” Hornbacher told the council. “Completing the drain line does provide that low-level outlet to the reservoir. So we do have an action item required by the dam safety division. If we do not comply with that in a method that is acceptable to them, then they are forced to take action. “

At another point, Hornbacher told the council, “We need a have plan in place, something that we can demonstrate within the next several years, 2017, that you know, we’ve got something already done or that we’re taking this tangible action,” Hornbacher said. “And certainly completing the drain line is that action. If we were to try to look at other mechanisms, that would either require us to make modifications at the reservoir or provide other types of facilities that could drain that reservoir.”

With that, and other statements, Hornbacher consistently backed-up to his professional recommendation that the city complete the pipeline. And he only mentioned in passing the existing low level outlet.

During public comment at city council on Oct. 27, Maurice Emmer, a former Aspen mayoral candidate and staunch opponent of the city’s hydro project, told the council that they should conduct their own research and not trust staff to give them all the information they might need to make a decision on projects such as Thomas Reservoir.

“Staff makes a proposal, then it gives city council information to support the proposal,” Emmer said. “It doesn’t give council information that might undercut the proposal.” (Meeting video starts at 19:01).

For example, Emmer pointed out that Hornbacher did not tell council that the dam had been inspected in 2012, or elaborate on how the existing low-level outlet might satisfy the state.

And Hornbacher did not know, when asked by Councilman Dwayne Romero, how often the state inspects dams.

“I was going to look that up and I didn’t,” Hornbacher said. “I would say it is somewhere between two to five years, I’m thinking it’s around three, which is why you know, we’ve got this report in 2017.”

The state historically has inspected dams classified as “high hazard” dams, which pose a threat to human life, every year. It inspects significant hazard dams, which only pose a threat to property, every other year, as in 2012 and 2014 in the case of Thomas Reservoir, which has been classified as a significant hazard dam since at least 2012.

It’s not clear why Hornbacher is citing a need to act by 2017, as Gleason, the dam inspector, said she would need proof of a low-level outlet by the next inspection, which is slated for 2016.

Hornbacher, when asked, also did not cite the date of the last dam inspection, which was April 4, 2012.

Thomas Leonard Reservoir was completed in 1966, although water had historically been stored on the site in wooden structures to feed an old hydro plant in the same location as the proposed plant.

In 1989, the state concluded the city’s dam was under 10 feet tall, and didn’t meet its definition of a “jurisdictional” dam. So they stopped inspecting it. At the time it was classified as low hazard dam.

Inspection reports in the early 1980s mention that the reservoir’s low-level outlet drains to the water treatment plant — and was considered acceptable.

In 2010, when the city went to install its new penstock/emergency drain line, it had to rebuild the north side of the reservoir to a height of 19 feet, which put the dam back under the state’s jurisdiction.

At that time, regulators saw that the dam, if breached, would damage some property below the reservoir, but not threaten any lives, and gave it a significant hazard classification. That did not change at the May inspection, as Hornbacher implied on Oct. 21.

As to the overall damage that would be caused if the dam failed, a 2011 report by the city’s consulting engineers, McLaughlin Water Engineers, stated that “it is unlikely that buildings or roads would receive extensive damage as a result of a dam breach at Leonard Thomas Reservoir.”

No other options?

By the time Hornbacher was through discussing the completion of the emergency drain line with council on Oct. 21, it was clear he had persuaded them that his proposal was the only safe and correct course of action for the city to take to meet the requirements of the May inspection report.

“So, summing it up for my purposes, this is a state-mandated action to put in this drain line?” Councilman Art Daily asked Hornbacher at the end of the discussion on Oct. 21.

In response to Daily, who is an attorney with Holland and Hart, Hornbacher seemed to choose his words carefully.

“The state mandates that we must have a low-level outlet,” Hornbacher said. “What we have available is a nearly completed low-level outlet, and that would meet the state requirements. So they are telling you, you have to do it. They don’t necessarily go and say this, this and this, is how.”

“But some sort of drain line has got to go in?” Daily asked.

“Yep, a low-level outlet has got to be established in there for emergency, you know, release of water or draining the reservoir,” Hornbacher said.

“I guess, then the last question that comes to my mind is, are there any more equally efficient but more cost effective means of resolving the state requirement versus … this is the best solution?” Daily asked.

“This is a really enduring and complete solution, and by that I mean that you’ve got this hardened route that takes it to the stream and empties into the stream without further erosion or damage there at the stream, you’ve sort of dissipated the energy,” Hornbacher said. “Any other option that you might pursue to get water out of that reservoir does not have such a direct route, so you’d be either placing that water in an unimproved, sort of drainage-like way, and movement of such water would then … start to erode, and cause other types of damage, and then … basically recovery costs or other impacts we can’t even foresee today.”

However, it is also possible that there may be simpler and less expensive ways to meet the state’s requirements for a low-level outlet, without completing the emergency drain line — which the state has never required the city to install. And that’s what Hornbacher said on Friday he is now looking into.

In fact, as Hornbacher briefly alluded to early in his remarks on Oct. 21, and confirmed on Friday, there is a low level outlet already in place at the reservoir, and it sends water to the water treatment plant, where it can then be released down to Castle Creek.

All the state is requiring of a low-level outlet at Thomas Reservoir is that it be able to move 1 cubic feet per second (cfs) of water out of the reservoir over a five-day period, which would lower the water level by five feet — a state standard that technically doesn’t even apply to reservoirs as small as Thomas Reservoir.

Under the “Outlet” section of her May 27 dam inspection report, Gleason wrote “it is our understanding that the only active outlet(s) discharge into the water treatment plant. According to Rule 5.9.6.2.1, a low-level outlet is required to draw down the reservoir under emergency conditions. Please either provide documentation of an existing bypass for treatment plant flows, or provide a low level outlet for the reservoir.”

May was the first time Gleason had inspected Thomas Reservoir. She inspected another 60 dams this summer and said she will review issues identified in those inspections throughout the winter.

As a state dam safety engineer, Gleason said she has wide latitude to work with dam owners, such as the city, to come up with reasonable solutions to concerns raised during inspections.

According to a safety manual published by the state in 2002, “follow-up of the inspection often includes reviewing questionable conditions on site with the dam owner, explaining the problems and suggesting the best and/or most economical way to proceed in assuring the dam’s safety. Frequently, further studies by a consulting engineer are recommended.”

“We work with the owner to make sure we are not requiring something that they can’t afford,” Gleason said. “The city could propose having a stand-by generator, a pump and a hose on site. Our office would typically accept such a solution.”

Hornbacher, in his response to Daily or other council members, did not bring up the pump-and-hose option.

Editor’s note: The Aspen Daily News collaborated with Aspen Journalism on this story and published in Monday, Nov. 3, 2014. Aspen Journalism was responsible for an error in the printed version of the Daily News story, as well as the initial digital version, as we said David Hornbacher is a licensed engineer, and he is not.

More hydroelectric/hydropower coverage here.


Aspen drinking water tour recap

September 23, 2014

Aspen

Aspen


From the Aspen Daily News (Collin Szewczyk):

Through a program by the Roaring Fork Conservancy, a group of over 20 people seeking to quench their intellectual curiosities concerning the city’s water, how it’s treated and where it comes from, toured the city of Aspen’s drinking water treatment facility this week led by water treatment supervisor Charlie Bailey and Laura Taylor, an operator at the facility.

Christina Medved, watershed education director of the Roaring Fork Conservancy, pointed out the parameters of the Roaring Fork watershed, noting that local rivers and streams are fed from an area the size of a small Eastern state.

“Our watershed is about the size of Rhode Island,” she said. “And over 30 percent of it is in designated wilderness areas.”

She praised the relationship that the conservancy has with local government entities such as the city water department, that allows visitors to check out local facilities, which are normally closed to the general public.

“What’s really exciting is we get access to places like this,” Medved said. “We have really wonderful partners that will say, ‘yeah, we’ll open up the gate for you,’ when you normally can’t get in here and have an audience with Charlie and Laura because they’re busy bringing water to Aspen.”

Aspenitus
The plant was completed in December 1966 after Aspen endured a major waterborne epidemic of giardia in the mid-1960s. Giardia is a microscopic parasite that is found in soil, food or water that is contaminated with feces. Another parasite, cryptosporidium, has yet to appear in the Aspen area.

“That was 1964-65; it was the first documented public health problem in the United States,” said Bailey. “There was a documented waterborne problem and that was giardia. There were two redwood tanks up on the hill here that were used for the hydro plant that was down the street, but the Aspen Water Company provided water to the pipes and there was no treatment at all … It was a big hit, they called it ‘Aspenitus.’”

After the outbreak, the city got money together, bought bonds and broke ground on the treatment plant in 1965. There’s been no cases of giardia in the city’s water since the building of the facility, Bailey said.

“There’s lots of giardia in the water and none of it comes out of the pipeline here,” he said. “We’re required to do testing once a year on the performance of our filters and our clear well (a reservoir used for storing filtered water, which flows through a series of baffles, allowing contact time with chlorine for disinfection).”

Beavers were the main culprit for the giardia epidemic, and the area up Maroon and Castle creeks was teeming with them at the time.

“There was a huge beaver population up there,” Bailey said, but added that it’s good to have them in the area. “They’re animals that let us know that the environment is healthy.”

The water plant also checks the water for mining tailings and other non-natural pollutants.

“We’ve requested extra testing of our water sources,” Bailey said. “We’ve done heavy metal testing and we actually do [pharmaceutical] testing, too.”

He added that no traces of either have been found in Aspen’s drinking water.

“Ever since I’ve been here, and even before, there’s been no problem with city water,” he said. “No public outbreaks, no boil orders, because I will not let it happen on my watch.

“We make the water, and the best thing about making the water here is that it’s clean,” Bailey continued. “The water comes from wilderness areas and there is nobody up above us that has dumped back [into the creeks] after industrial processes or anything like that. We get water coming through the geology, through the snowmelt, we are stewards of the water so we really keep track of everything above us and below us.”[…]

The water here is pumped in from Maroon and Castle creeks and begins its journey through the treatment facility and into Aspen taps. He noted that the city has water rights of 142 cubic feet per second (cfs) in Maroon Creek and about 90 cfs in Castle Creek, even though the streams only hit that level during spring runoff…

The purification process
The reservoir, which holds about 4 million gallons in the summer, is the first stop in the purifying process as sediment in the water begins to settle here.

“This is one of our processes,” Bailey said. “We basically bring the water in here and we slow it down. This helps so much during [peak] runoff … the dirt is tumbling, it’s coming in and all the sudden it settles out here and we’re able to draw off the surface and it’s much, much cleaner.”

He added that the water is usually at about one turbidity unit (TU) — the measurement of cloudiness caused by particulates — when it enters the reservoir. When it leaves it’s at .5 TU; during peak runoff it can be as dirty as 60 TU.

“We get reduction in here,” Bailey said. “That’s just a natural tumbling process, we slow it down and that stuff just falls out.”

The nutrient-rich sediment has to be periodically dug out, but it gets spread around the site making the soil perfect for plant growth.

To the north side of the reservoir lies the remnants of the old Maroon Creek flume that was used to divert water to the “tent city” in the late 1800s. As the group was looking down on the wooden channel one observer noticed a bear hanging out in a nearby tree, adding to the natural feel of the site.

The water next goes into large flocculation tanks — which look like UFOs — that, with the aid of chemicals, coagulate the particulates, churn them about and make the sediment again settle to the bottom.

After settling twice, the water makes its journey to a filtration section of the facility. Here, it’s pushed by gravity through a filter that consists of 18 inches of anthracite (coal) and a foot of sand. It next heads to the clear well for 14 to 15 hours to ensure all giardia is killed.

The state’s regulation allows for drinking water to reach one TU and still be acceptable to drink, but on this day Aspen’s drinking water was a pristine 0.037 TU.

More water treatment coverage here.


Conservation: Big water savings in Aspen — Mountain Town News #ColoradoRiver

June 30, 2014

Smuggler Mine back in the day via GregRulon.com

Smuggler Mine back in the day via GregRulon.com


From the Mountain Town News (Allen Best):

In 1974, Aspen’s future seemed clear enough. The town was growing briskly, the ski industry booming, and by the 1990s the town would need to make major investments to provide water for the future.

With that in mind, town officials filed for storage rights on two upstream creeks, Castle and Maroon, where the municipality already had significant senior water rights. Had the town gone ahead with construction of those reservoirs, the cost today would be roughly $50 million.

Instead, in about 1994, Mayor John Bennett and council members chose a different approach. They would emphasize water savings.

Phil Overeynder, who was the city’s utility manager then, says he has calculated that today water rates would need to be quadrupled to pay for the reservoirs and other infrastructure.

But there was another reason for Aspen to pursue conservation beginning in the 1990s. Overeynder said improved efficiency bolstered the argument that Eastern Slope water providers needed to make do with what they had before expanding diversions. In his eyes, Eastern Slope water providers still have not done everything they can. “Not to the extent it was promised 40 years ago,” he says.

For Aspen, improving water efficiency has several components. The city couldn’t account for 55 percent of the water being sent to customers. There were leaks, lots of them. It was, says Overeynder, a third-world water system. But a lot of water was used to bleed pipes. Water mains were buried deep, but the service lines to individual houses were within the frost line. During winter, homeowners left their faucets running, to avoid freezing. It was city policy to overlook that use.

Over time, these inefficient uses have been eliminated. The rate structure was revised to strongly recommend efficiency.

From 450 gallons per capita daily in 1974, use peaked in 1993 at 516 gallons.

Last year, it was 164 gallons per capita daily.

Use still spikes in summer, but not as much. The water treatment plant expanded in the 1980s has surplus capacity.

More Roaring Fork River watershed coverage here.


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