Water restrictions still in effect in Sterling — The South Platte Sentinel


From The South Platte Sentinel (Delinda Korrey):

As a reminder to residents, mandatory outdoor water restrictions are as follows:

“If your street address is an odd number, you may water on Tuesday, Thursday and Saturday.

“If your street address is an even number, you may water on Wednesday, Friday and Sunday.

“On whatever watering day your neighborhood is designated, there are no restrictions on the time you may water.

“No one, however, is allowed to water on Mondays.

“Personal vehicles may be washed only on one’s watering day.

“Restaurants may serve water only upon request.

“Vehicle fleets and vehicles in auto dealerships may not be washed more than once a week.

“Golf courses utilizing City water shall not water roughs.

“Trees, shrubs, perennials, annuals and vegetable gardens may be watered by hand, soaker hose or trickler system any day. Hand watering means holding a hose in the hand or with a watering can. It does not allow sprinkling.

“A warning will be given for the first violation. The second violation will carry a penalty of $50, third violation $150 and all subsequent violations $250, and the possibility of having a flow restrictor installed on the water line.”

It’s not fair for you to break the law when your neighbor isn’t. It’s been said the best time to plant a tree is 20 years ago and the best time to conserve our water is before the well runs dry.

Sterling: Precipitation events cause headaches for wastewater infrastructure

Wastewater Treatment Process
Wastewater Treatment Process

From the Sterling Journal-Advocate (Sara Waite):

Rob Demis of Hatch Mott MacDonald didn’t have good news when he gave an update on his company’s review of Sterling’s wastewater treatment plant during Tuesday’s Sterling City Council meeting.

The engineering firm, which was contracted by the city to look at what improvements will be needed at the plant, has been working on the review for three months, but they are still looking at the data and developing preliminary alternatives.

The company has identified two primary issues facing the city’s system: flooding and improvements necessitated by upcoming changes to regulations.

Demis noted that the system has experienced multiple flooding events at the headworks facility in the last five years, from flooding of the river and heavy rainfall events. The flooding damages to equipment and pumping, overloads the pumping system and treatment plant, overflows into the river and leads to violations of the city’s wastewater permit. Each event can cost around $50,000 to $75,000 to replace the damaged equipment.

Inflow and infiltration are the factors that lead to flooding. The water comes from leaky pipe joints, roof drain connections, leaky manholes, missing manhole covers — storm water coming into the waste water system — as well as leaky customer sewer lines and sump pumps, Demis said. He added that Sterling’s system is relatively old; the design life of pipes is about 50 years, so pipes that have been in the ground since 1966 or earlier are at the end of their useful life. “It’s now time to start thinking about fixing them, or at least trying to slow down the amount of leaks,” he said.

He showed a graph that looked at a significant rain event. Prior to the storm, the typical influent flow to the system was averaging about 1.7 million gallons per day. The rain event exceeded the system’s pumping capacity, so the total amount of inflow isn’t known, but Demis noted that for two weeks following the storm, inflow remained above average. He said that is due to infiltration from groundwater leaking into the sewer system.

Sterling needs a larger pumping capacity, and with it a larger pipe to carry the waste water to the treatment plant. Demis said the city also needs to put in 30 million gallons of storage so when there is above average flow, that water can be fed slowly into the treatment plant and allow the biological processes to occur, which prevents violations.

Changes to regulations as soon as next year will require additional processes at the treatment plant. In November 2017, Sterling will have to meet a Total Inorganic Nitrogen (TIN) limit of 10 mg/L of Nitrogen when discharging to the recharge basins, which it cannot do. By 2022, the city will face limits on nitrogen and phosphorus that it also cannot meet.

The city will need additional tanks and chemical systems for nutrient removal as well as new process equipment, and new clarifiers as the existing ones are at the end of their life. The new equipment will necessitate upgrades to the electrical system, and they will need to implement a process control system to ensure they are meeting the requirements.

Demis noted that nitrogen and phosphorus are popular fertilizers, and they promote the growth of algae, which can kill fish.

Demis told the council he would make further presentations as they complete analysis of the data and the options available to the city.

Sterling: New RO water plant online and slowly winning over rate payers

Reverse Osmosis Water Plant
Reverse Osmosis Water Plant

From Radio Colorado College (Maeve Conran):

Coloradans pride themselves on the quality of their drinking water, most of which originates high up in the Rocky Mountains. But many communities on the Eastern plains have water that not only tastes bad, it’s out of compliance with federal drinking water standards.

Many diners at the J and L Cafe in downtown Sterling are sipping on glasses of tap water as they enjoy lunch on this December morning. That was not the case just a year ago.

“You couldn’t hardly drink it,” says Kathy Orchid, who says she never used to drink the tap water. “You could hardly drink it. It’s much better.”

The difference lies in the new multi-million dollar water treatment plant, less than a mile from the diner.

“The EPA…put the city on an enforcement order where we were basically told we had to fix the problem,” says Jeff Reeves, Sterling’s utilities superintendent, who supervises operations.

The city and the state had long been aware of problems with the drinking water, specifically that it contained radium and uranium, contaminants that can lead to kidney problems and bone cancer.

“All of these problems are naturally occurring,” says Ron Falco, who manages the Safe Drinking Water Program for the State of Colorado. “So this problem happens in the ground water as it’s moving through formations that may just have naturally high levels of radium or uranium.”

Falco says dozens of other communities, all on the Eastern Plains, are also struggling with water quality because like Sterling, they rely on ground water.

The EPA issued new drinking water standards in 2008, which meant those locations were now out of compliance with federal standards. Falco and other state health officials started working with the communities to improve the water systems.

“Historically, about 55 systems in the state of Colorado serving about 32000 people have struggled with uranium and radium in their drinking water,” says Falco. “By 2008, that number was at about 37 systems and about 21000 people.”

Sterling’s new water treatment plant is about a year old, and has put a dent in those numbers. This town of about 15,000 people in the South Platte River Basin was the largest municipality in the state facing this water quality issue.

The plant uses reverse osmosis to remove the uranium and radium. Reverse osmosis forces the water through a membrane, trapping contaminants which then form a concentrated brine.

But there are a couple of challenges. One is a 15% loss in usable water due to the treatment process, a significant figure for a region grappling with water quantity AND quality. The other problem is what to do with that wastewater.

Deep injection well
Deep injection well

Utilities manager Jeff Reeves says they’re storing that wastewater in an underground reservoir. “That’s down below an impermeable layer so it can’t get back up into the drinking water.”

Despite those two challenges, Reeves says the city of Sterling now has water that is well within federal standards. In addition, the reverse osmosis process has also improved the taste.

“We thought that we might as well make the water much more aesthetically pleasing,” says Reeves. “If you’re going to produce a product that people are going to have to pay for it’s a lot easier to get along with the customers if the water is good.”

More water treatment coverage here.

Sterling water treatment system wins award — Sterling Journal Advocate

Reverse Osmosis Water Plant
Reverse Osmosis Water Plant

From the Sterling Journal Advocate (Sara Waite):

Last week, the American Council of Engineering Companies of Colorado announced the project was one of four to receive a 2015 Engineering Excellence Award for “outstanding engineering accomplishments.”

The water treatment system came online about a year ago, five years after city received an enforcement order due to levels of uranium and trihalomethanes above the drinking water standard allowed by the Environmental Protection Agency. To address that issue, as well as high levels of sulfate and total dissolved solids, the city opted to construct a new reverse osmosis water treatment plant. The plan featured a challenge because of the uranium — the result of runoff over naturally occuring uranium deposits upstream — that would end up in the treatment brine.

Engineers with Hatch Mott MacDonald came up with a solution: coupling the reverse osmosis system with EPA Class 1 deep injection wells to dispose of the waste water.

“The result enabled the city to meet its water quality goals to provide 14,000 residents with safe, clean and aesthetically pleasing drinking water — and building a 9.6 million gallon per day water treatment plant without incurring the costs and risks associated with the disposal of uranium contaminated waste,” the award announcement states.

The 7,000-plus foot wells pump the contaminant deeper than water that is used for drinking water.

The project was funded with a voter-approved $29 million loan from the Drinking Water Revolving Fund through the Colorado Resources and Power Development Authority.

City Manager Don Saling called the award “quite an honor for the engineers.” He added that the well drilling company has asked to use the wells for a case study.

He said the water treatment system was an example of a “great plan” using “great technology.”[…]

According to the ACEC-CO release, the winning projects are ranked by a panel of judges representing a cross section of industry, academia and media, assemble to rank the submissions on engineering excellence. Projects in the competition are rated on the basis of uniqueness and innovative applications; future value to the engineering profession; perception by the public; social, economic, and sustainable development considerations; complexity; and successful fulfillment of client/owner’s needs, including schedule and budget. The other projects receiving top honors were the Denver Union Station Redevelopment, new Transit Center, and Pecos Street over I-70 Bridge Replacement.

2015 Engineering Excellence award-winning projects will advance to ACEC’s national competition in Washington D.C., which will be held in April next year.

For more information, visit http://acec-co.org.

More water treatment coverage here.

Sterling: “AgFest” recap

Groundwater movement via the USGS
Groundwater movement via the USGS

From the Sterling Journal-Advocate (Callie Jones):

This year’s festival included 10 stations, including the GPS mapping station, where Morgan County Extension Agent Marlin Eisenach spoke about how farmers use GPS mapping to plow, so they don’t use too much agricultural herbicide or insecticide and they can save as much fuel as possible…

At the groundwater station, Extension Agent Molly Witzel, from Burlington, spoke about watershed, an area where smaller bodies of water flow into bigger bodies of water; an aquifer, “a big underground lake;” and other groundwater terms. She also spoke about what happened during the South Platte River flood last fall…

A rangeland ecology station had students learning about the different plants and animals that can be found on rangeland. Logan County Extension Agent Casey Matney talked about the importance of rangeland, because it has trees, animals and water.

At a plant science station the fifth graders learned about the difference between dicot and monocot plants, they got to see different types of seeds and they learned about how plants grow.

Sterling: ‘The plant is doing what it was built to do’ — Jim Allen

Reverse Osmosis Water Plant
Reverse Osmosis Water Plant

From the Sterling Journal-Advocate (Sara Waite):

…Allen said they have yet to receive any reports of discolored water, and there is no evidence of issues with lines breaking due to the new water. He said he didn’t believe a problem last week with the service line to Pizza Hut was due to the water treatment system, although he acknowledged it would be hard to prove either way. But, he said, when the problem arose and city crews dug up the line, they found it was an old lead service line, which they usually replace anyway with newer materials.

Allen was reluctant to talk about the probability of those problems — he said he doesn’t like to discuss things he doesn’t want to happen — but he was happy to report that the uranium levels in the water, which prompted the need for the new treatment plant, are falling. The membranes (in the reverse osmosis system) are working, he said.

He said that the newly treated water likely has not fully replaced the “old” water in the system, as it has to cycle through the storage tanks and into the water service. The timeline on that depends on the volume of water in storage and usage.

The water is safe to drink, he reiterated.

“The plant is doing what it was built to do,” he said.

The price tag for Sterling’s deep injection wells for RO brine escalates from $80,000 to $2.3 million


From the Sterling Journal-Advocate (David Martinez):

[Sterling Public Works Director Jim Allen] told the council that Public Works was working on a number of water and sewage issues around the city – most of them directly or indirectly related to construction of the new water treatment plant.

The one that stands out: Deep injection wells used to pump the treated wastewater from the reverse osmosis filtration, estimated to cost $80,000 at the start of the project, will now cost about $2.3 million, according to a March 10 estimate. About $1.3 million of that cost would go toward the construction of one of the two pumps, which is located above the railroad tracks north of the plant…

The wells themselves, buried about 7,000 feet underground, have already been constructed. They were included in one of three bid packages for the project – the other two being a pipeline project and the water treatment plant itself, which is in the final construction stages.

Allen told the council the increased cost comes from the pumping equipment needed, as well as some stainless steel piping needed for the aboveground operation. The pipes might need to handle 2,200 to 2,600 pounds of pressure per square inch, which Allen said is a “monumental number.”[…]

Allen told the Journal-Advocate the $2.4 million also isn’t set in stone; he, Kiolbasa and others will be working with the estimates for a more solid cost…

In related projects concerning the plant, Public Works is continuing to redrill and rehabilitate the city’s raw water wells. The effort is part of a plan to have enough raw water to actually put through to the water treatment plant.

In February the council heard that the plant planned on having the ability to pump more than 7,900 gallons of water per minute, but that it could only pump about 5,500 gallons at that point because of degraded wells.

More infrastructure coverage here.