Floating #Solar Is Best Solution For Walden’s High Electric Bills — CleanTechnica.com #ActOnClimate

From CleanTechnica.com (Charles W. Thurston):

When a town has high electric bills and no available land for a solar farm, a floating solar plant on the pond of a waste water plant makes great sense. Walden, Colorado, population 750, elevation 8,000 feet plus, and land area of 0.34 square miles, is such a town.

Photo credit: CleanTechnica.com

“We were spending about $22,000 a month for electricity for the water treatment facility, and this 75 kW solar installation will save us $10,000 a month,” says Jim Dustin, mayor of Walden, Colo. “We’ll pay for the plant in 20 years, and it is still expected to run 10 more years after that,” he says.

The plant technology was furnished by floating solar specialists Ciel & Terre USA and was installed by GRID Specialists. The $400,000 cost of the plant was offset by a $200,000 grant from the Colorado Department of Local Affairs, which manages revenues earned by oil and gas development tax in the state. The project also was supported by the Colorado Energy Office.

“The Energy Office is interested in this installation because it gets down to minus 40 or 50 degrees in the winter, and we have very high winds. They want to know if the technology will work, because there are irrigation ponds and unused water bodies all over this state,” says Dustin. The energy office has offered $120,000 to move the installation to another location if it doesn’t work in Walden, he adds.

The Energy Office is also interested in conserving water in the state, where evaporation reduces holding pond levels by up to 90 inches per year, according to Taylor Lewis, a program engineer at the agency. “We have 2,000 man-made reservoirs in the state to keep water so if we can identify a few where it makes sense to cover them with solar, there could be a double benefit of water savings and electricity generation,” he says.

The concept of covering drinking water bodies to reduce evaporation is not new. “I’ve been looking at claims by the City of Los Angeles that they have saved billions of gallons of water over the past 10 years at four reservoirs, using black floating plastic balls,” Lewis says. “We’re interested in studying the impact with floating solar here,” he adds.

Johnson Controls came up with the initial idea of a floating solar array for Walden, says Dustin. “The floating solar array is a milestone for the Town of Walden and highlights the potential for Colorado’s overall energy efforts,” said Rowena Adams, a Performance Infrastructure account executive at Johnson Controls, in a statement.

“It was a practical choice for Walden given the surrounding bodies of water and the town’s energy resiliency efforts at the Town Water Treatment Facility, as well as the desire to conserve water and minimize algae growth,” Adams said.

Ciel & Terre, the technology provider, has more water projects in mind for Colorado. “With demand for solar power continuing to rise and available real estate becoming more expensive, floating solar is the ideal solution for anyone with a manmade pond or body of water. It’s cost-effective, quick to install, easy to maintain, and offers a variety of environmental benefits,” said Eva Pauly-Bowles, the representative director for the US office of the French company.

“Floating solar is no longer an exotic niche in the US, but a rapidly growing sector of the solar market. Ciel & Terre USA has other larger floating solar projects under construction and planned across the country,” Papuly-Bowles said.

Deploying a floating solar array on manmade bodies of water improves energy production by keeping the solar system cooler, Ciel & Terre says. At the same time it reduces evaporation, controls algae growth, and reduces water movement to minimize bank erosion, it says. Floating solar arrays also make optimal use of pond surfaces, providing clean solar energy without committing expensive real estate or requiring rooftop installations, the company adds.

Established in 2006 as a renewable Independent Power Producer (IPP), Ciel & Terre has been fully devoted to floating solar PV since 2011. The French company pioneered Hydrelio, the first specific and industrialized system to make solar panels float on water, with criteria such as cost-effectiveness, safety, longevity, resistance to winds and waves, simplicity, drinking water compliance, and optimized electrical yield, the company states in its profile.

Ciel & Terre has floating solar installations in Japan, Korea, China, UK, France, Brazil, Singapore, Malaysia, Italy, and Taiwan as well as the United States. The company has its United States headquarters in Petaluma, California.

Water Education Federation: Teams From University Of British Columbia, University Of Colorado Win 2018 Student Design Competition

Wastewater Treatment Process

Here’s the release from the Water Education Federation via Water Online:

The Water Environment Federation (WEF) proudly announces students from the University of British Columbia and University of Colorado as winners of the 2018 Student Design Competition. The 17th annual competition took place during WEFTEC 2018, WEF’s 91st annual technical exhibition and conference.

The University of British Colombia team’s project, “Ellis Creek Remediation,” won in the Environmental Design category, and the University of Colorado – Boulder team’s project, “Enhancing Nutrient Removal at Boulder’s 75th Street Wastewater Treatment Facility,” won in the Wastewater Design category. This was the third win for the University of British Columbia (British Columbia Water & Waste Association) and the fourth win for University of Colorado – Boulder (Rocky Mountain Water Environment Association).

As a program of WEF’s Students & Young Professionals Committee, the competition promotes real-world design experience for students interested in pursuing an education and/or career in water/wastewater engineering and sciences. It tasks individuals or teams of students within a WEF student chapter to prepare a design to help solve a local water quality issue. Teams evaluate alternatives, perform calculations, and recommend the most practical solution based on experience, economics, and feasibility.

Members of the University of British Columbia team included James Craxton, Johnson Li, Steven Rintoul, Luthfi Subagio, and their faculty adviser, Dr. Noboru Yonemitsu. Members of the University of Colorado – Boulder team included Katie McQuie, Mercedes Kindler, Debbie Cevallos, Feng Xiang, Dome Cevallos, Jackie Kingdom, and their faculty adviser, Dr. Christopher Corwin. Both teams received certificates and their respective member associations will receive a $2,500 award.

Greeley and Hansen, Black & Veatch, CDM Smith, and Wisconsin Economic Development Corporation sponsored this year’s competition. Click here to learn more about the WEF Student Design Competition.

About WEF
The Water Environment Federation (WEF) is a not-for-profit technical and educational organization of 35,000 individual members and 75 affiliated Member Associations representing water quality professionals around the world. Since 1928, WEF and its members have protected public health and the environment. As a global water sector leader, our mission is to connect water professionals; enrich the expertise of water professionals; increase the awareness of the impact and value of water and provide a platform for water sector innovation. For more information, visit http://www.wef.org.

Sterling councillors are asking voters to fund a new wastewater treatment plant

Photograph of Main Street in Sterling Colorado facing north taken in the 1920s.

From The Sterling Journal-Advocate (Sara Waite):

At their regular meeting Tuesday, the Sterling City Council approved a resolution asking voters to take out a loan of up to $37 million to replace aging infrastructure and address “inflow and infiltration” issues. The interest rate on the bond would not exceed 3.25 percent.

City Manager Don Saling assured the council that the actual debt and interest rates should be less than the city is asking for, but the cost of the project has not been completely nailed down, and interest rates are also fluctuating. Because of that, he said, “limits were set conservatively.”

Repaying the wastewater bond will require city sewer rates to go up, but how much has not been identified. The council has been awaiting the results of a rate study for water and sewer services that looked at infrastructure needs, debt service and operational costs, but an evaluation of the wastewater treatment system done in 2016 by engineering firm Mott MacDonald suggested they go up $23. Since then, the city has implemented flat rate hikes annually, in anticipation of higher rates to pay for the required system upgrades.

The ballot question specifies infrastructure improvements that include changes to the headworks building, which suffered extensive flood damage in 2013; replacing the existing force main and constructing a redundancy in case of failures; modifications to the main plant; lift station replacements and corrective measures for the collection system. One of the problems the system has is leaks from the storm sewer system that can flood the wastewater lines and disrupt the treatment process after heavy rain events.

Failure to make the improvements could result in hefty fines from the Colorado Department of Public Health and Environment, as much as $10,000 from the date of the first violation in November 2017.

@Denver Water, Aurora in dispute with state over lead treatment — @WaterEdCO

Roman lead pipe — Photo via the Science Museum

From Water Education Colorado (Jerd Smith):

Denver Water and three other organizations are seeking to overturn a state order that directs Denver to adopt a strict new treatment protocol preventing lead contamination in drinking water.

Denver is not in violation of the federal law that governs lead, but it has been required to monitor and test its system regularly since 2012 after lead was discovered in a small sample of water at some of its customers’ taps.

In March of this year, after Denver completed a series of required tests and studies, the Colorado Department of Public Health and Environment (CDPHE) ordered the utility to implement a treatment protocol that involves adding phosphates to its system. It has until March of 2020 to implement the new process.

Denver, which serves 1.4 million people in the metro area, has proposed instead using an approach that balances the PH levels in its treated water and expands a program replacing lead service lines in the city. Old lead service lines are a common source of lead in drinking water.

Treating lead and copper in water systems is a complex undertaking governed by the federal Lead and Copper Rule. In Denver, for instance, there is no lead in the water supply when it leaves the treatment plant. But it can leach into the supply via corrosion as water passes through lead delivery lines and pipes in older homes. Denver has 58,000 lead service lines in its system. Lead has continued to appear in samples it has taken at some customers’ taps, according to court filings, though not at levels that would constitute a violation of the federal law.

Eighty-six samples taken since 2013 have exceeded 15 micrograms per liter, including one tap sample which measured more than 400 micrograms per liter, according to court filings. The 15-microgram-per-liter benchmark is the level at which utilities must take action, including public education, corrosion studies, additional sampling and possible removal of lead service lines.

In response to the state’s order, the City of Aurora, the Metro Wastewater Reclamation District and the nonprofit Greenway Foundation, which works to protect the South Platte River, sued to overturn it, concerned that additional phosphates will hamper their ability to meet their own water treatment requirements while also hurting water quality in the South Platte. Denver joined the suit in May.

Because Denver Water services numerous other water providers in the metro area and participates in a major South Metro reuse project known as WISE, short for Water Infrastructure and Supply Efficiency, anything that changes the chemical profile of its water affects dozens of communities and the river itself.

Among the plaintiffs’ concerns is that phosphate levels in water that is discharged to the river have to be tightly controlled under provisions of the Clean Water Act. If phosphate levels in domestic water rise, wastewater treatment protocols would have to be changed, potentially costing hundreds of thousands of dollars, if not more, according to a report by the Denver-based, nonpartisan Water Research Foundation.

From an environmental perspective, any increased phosphate in the South Platte River would make fighting such things as algae blooms, which are fueled by nutrients including phosphorous, much more difficult and could make the river less habitable for fish.

But in its statement to the court, the CDPHE said the state’s first job is to protect the health of the thousands of children served by Denver Water in the metro area.

“The addition of orthophosphate will reduce lead at consumers’ taps by approximately 74 percent, as opposed to the cheaper treatment favored by plaintiffs [PH/Alkalinity], which will only reduce levels by less than 50 percent,” CDPHE said in court documents. “This is a significant and important public health difference, particularly because there is no safe level of lead in blood…Even at low levels, a child’s exposure to lead can be harmful.”

How much either treatment may eventually cost Denver Water and others isn’t clear yet, according to state health officials, because it will depend in part on how each process is implemented.

Denver, Aurora and Metro Wastewater declined to comment for this story, citing the pending lawsuit.

The Greenway Foundation did not respond to a request for comment.

In late July, all parties agreed to pause the legal proceedings while they examine water treatment issues as well as the environmental concerns raised by higher levels of phosphorous in Denver Water’s treated water supplies. If a settlement can’t be reached by Nov. 1, the lawsuit will proceed.

Jonathan Cuppett, a research manager at the Water Research Foundation, said other utilities across the country may be asked to re-evaluate their own corrosion control systems under a rewrite of the Lead and Copper Rule underway now at the U.S. Environmental Protection Agency.

The newly proposed federal rule is due out for review later this year or by mid-2019.

Cuppett said the changes may lean toward more phosphate-based treatment for lead contamination. In fact, the EPA issued a statement in March in support of the CDPHE’s order to Denver Water.

“Within the [Lead and Copper Rule] there are a variety of changes that may be made. Depending on what those changes are other utilities may have to evaluate their strategy again or more frequently. And if that is the case, we may see more of this issue where someone is pushing for phosphorous for control for public health, creating a conflict of interest with environmental concerns,” Cuppett said.

Colorado public health officials said they’re hopeful an agreement can be reached, but that they have few options under the federal Safe Water Drinking Act’s Lead and Copper Rule.

“The [Lead and Copper Rule] is a very prescriptive, strict rule,” said Megan Parish, an attorney and policy adviser to CDPHE. “It doesn’t give us a lot of discretion to consider things that Metro Wastewater would have liked us to consider.”

@WaterEdCO “Fresh Water News’: Aurora’s recycled water plant running at full-tilt

From Water Education Colorado (Jerd Smith):

Aurora’s futuristic recycled water project — Prairie Waters— is running at full-tilt for the first time in its eight-year history, a move designed to make the city’s water supplies last longer in the face of severe drought conditions.

“We’re pushing it as hard as we can,” said Greg Baker, a spokesman for Aurora Water.

In February, as mountain snows failed to accumulate, Baker said the city began mobilizing to ramp up plant operations, knowing its reservoirs would likely not fill this summer. “We were very worried.”

By April, Prairie Waters was running at full speed, generating 9.7 million gallons a day (MGD), up from 5.1 MGD last summer, a 90 percent increase in production.

“We could possibly push it to 10 MGD,” said Ann Malinaro, a chemist and treatment specialist with Prairie Waters, “but we consider 9.7 MGD full capacity.”

[…]

“Prairie Waters was huge, not just in terms of volume, but also because it’s really helped us advance as a state in accepting potable [drinkable] reused water,” Belanger said. “Historically, there has been a yuck factor. But Prairie Waters has helped folks understand how systems can be designed so they are safe and effective.” [Laura Belanger]

Twenty-five Colorado cities, including Denver, Colorado Springs, Fort Collins and Louisville, operate recycled water facilities, according to the Colorado Department of Public Health and Environment, but that water is used primarily to water parks, golf courses and to help cool power plants, among other nonpotable, or non-drinkable, uses.

But Aurora, faced with fast-growth and a shortage of water, realized more than a decade ago that reusing its existing supplies and treating them to drinking water standards was the only way to ensure it could provide enough water for its citizens.

Completed in 2010, the Prairie Waters Project recaptures treated wastewater from the South Platte River and transports it back to Aurora through a series of underground wells and pipelines. As the water makes its 34-mile journey from a point near Brighton back to the metro area through subsurface sand and gravel formations, it undergoes several rounds of natural cleansing.

Once it reaches the Prairie Waters treatment facility near Aurora Reservoir, it runs through a series of high-tech purification processes using carbon filters, UV light and chlorine, among other chemicals. Then, before it is delivered to homes, the reused water is mixed with the city’s other supplies, which derive from relatively clean mountain snowmelt that is carried down from the mountains.

Sterling voters will likely be asked to decide bonding for wastewater infrastructure in November

Wastewater Treatment Process

From The Sterling Journal-Advocate (Sara Waite):

The problems faced by the wastewater system have become more urgent, as the city is now non-compliant with its existing discharge permit. Failure to move forward with upgrades could result in stiff penalties from the Colorado Department of Public Health and Environment, to the tune of $10,000 a day assessed from the first date of the violation last November.

The Sterling City Council has long known about deficiencies in the system; two years ago, Rob Demis of engineering firm Mott MacDonald gave a preliminary overview of some of the problems presented by the aging infrastructure. In short, the system suffers from flooding and leakage issues, and also is incapable of meeting new environmental standards…

According to Demis, the system lacks the capacity to handle heavy rainfall events or river flooding, and also suffers from leaks at multiple points that allow groundwater to seep into the wastewater stream. That excess water damages equipment, overloads the system and can lead to costly permit violations, as well as disrupting the biological process that breaks down the organic material in the water.

The system also is incapable of meeting its existing compliance schedules or new regulations that are slated to be implemented by 2022. It suffers from a lack of redundancy, leaving the city vulnerable to failures that would be “catastrophic,” Demis said, and also uses obsolete and dangerous equipment and processes.

Demis explained that much of the system has reached, or exceeded, its useful life and the problems the city is facing will only get worse over time. As an example, he said the four clarifiers that are in place had been banned by the time they were installed in 1995, begging the question of how Sterling ended up with them in the first place, and one of the tanks has failed and can’t be used.

As part of the presentation, Demis went over the estimated costs, 80 percent of which was for construction and the other 20 percent for legal, administrative, engineering, permitting and other costs associated with such a project. The cost of installing a new force main and improvements to the treatment system itself make up about half of the $31 million price tag.

Demis also spoke about possible funding sources. Grants are not reliable, he said; they looked at six possible grant sources and one they identified as a possibility has not received the expected funding because of low oil prices. A review of potential loan sources showed that the State Revolving Fund would provide a lower total cost in the long run versus private loans, because of the reduced interest rate. Either way, the city charter requires voter approval for taking on debt.

The city’s existing sewer rates have not kept up with the rate of inflation, Demis said. Using simple math, he estimated that residential sewer users’ rates would increase by $23, but noted that the city would have to complete a rate study to look at the more complex issues involved in determining the revenue necessary to make the recommended improvements, operate the system and invest in other needed infrastructure. The council is awaiting a report on such a rate study that was funded in the city budget last year.

During his October 2016 presentation, Demis gave credit to the operators at the wastewater treatment plant, saying they were “willing to make their job a little bit harder to try to find the value for the city” by reusing existing equipment and infrastructure where possible. He estimated that the cost to completely start over with a new wastewater system would be between $45 and 50 million. “We think there’s very good value for the city of Sterling there.”

Sterling residents for the past two years have seen increases on both water and wastewater services in an attempt to build up the enterprise funds and address infrastructure needs. According to City Manager Don Saling, the rate hikes were intended to narrow the gap between where rates were and where they’ll need to be, pending the outcome of the rate study. One big change he expects to see from the study is a recommendation to base sewer rates on usage; the rate would be calculated from water usage in cooler months, when users are not watering outdoors. A variable rate would be more equitable — a family of four would presumably pay more than a single retiree on a fixed income — and could also encourage water conservation to lower both water and sewer bills.

New #Colorado rules prompt Garfield County to update septic system rules

Septic system

From the Glenwood Springs Post Independent (Jon Nicolodi):

Garfield County is revising its onsite wastewater treatment system regulations following new regulations put forth by the state. Does this impact you? Considering the consequences of a poorly maintained onsite wastewater treatment system, and with approximately 3,500 out of about 17,000 housing units in Garfield County relying on onsite wastewater treatment systems, the answer could be “yes.”

Some homeowners like septic systems because they don’t have a regular sewage bill from their municipality. Instead, they must properly maintain their system, but they have control, and more ownership, of what goes into their system and how much and how regularly they have to pay for maintenance. By only flushing human waste and toilet paper, by properly disposing of chemicals, and by using a compost collection service or backyard system to break down cooking grease and other food waste, all maintenance is preventative. With care and preventative maintenance, septic system owners can save in the long run.

Septic systems go astray, however, when they aren’t cared for. Septic system leakage isn’t a foreign concept to health and environment officials. Toilet water leaking into the ground untreated might make its innocent way down through hundreds of feet of soil before being neutralized by the soil microbes. More likely, the wastewater will leak into a nearby stream, creating algal blooms and wreaking havoc on the balance of water quality in the ecosystem.

If your home isn’t connected to a public sanitary sewer system, you may be utilizing a private drinking water well. This water source may be near your septic system. Phosphorus, nitrogen and bacteria aren’t exactly the constituents of quality drinking water.

The Colorado Department of Public Health and Environment’s Water Quality Control Division adopted Regulation 43 nearly a year ago, and counties have until June 30th of this year to adopt versions of this regulation that are at least as stringent as the state’s. Among other items, the regulation specifies the categories and type of material installed in and around the leach field, and it requires additional inspection of systems to ensure that they meet industry standards.

Septic systems should be inspected at least every three years, and typically pumped free of their settled solids every three to five years. Contact your local county officials to learn what you have on your site, and to learn who to call for a quality service provider. Be thoughtful about what you put down the drain and how much you use your garbage disposal. Mark the free hazardous waste collection day at the local landfill on your calendar. Practice water conservation by installing high-efficiency toilets, shower heads and laundry machines. Take one more step to being considerate of your local streams, and of your own and your community’s drinking water supply.