New Boulder Creek stretch through Eben G. Fine Park designated ‘impaired’ by state — The Boulder Daily Camera

E.coli Bacterium

From The Boulder Daily Camera (Sam Lounsberry):

State officials last month designated a new, and popular, stretch of Boulder Creek from the mouth of Boulder Canyon through the park as “impaired” due to elevated levels of E. coli.

But tubers, swimmers, fishermen and women will still likely be able to take a dip this summer if they wish.

The new designation by the state for the creek’s west Boulder stretch adds to the existing impairment of the waterway from 13th Street east to its confluence with South Boulder Creek, according to Colorado Water Quality Control Division spokesperson Ian Dickson…

The determination was made based on a “robust” data set of measurements for the E. coli bacteria, Dickson said.

“Every two years, the (state health) department works with the (Water Quality Control) Commission to examine water quality data and identify impaired waters,” Dickson said. “… The department thanks city of Boulder for this information, and we encourage communities to continue to send data so we can work together to protect the environment.”

Boulder spokesperson Meghan Wilson said the city is working on a communication strategy for informing residents and potential creek users of the newly designated impaired stretch of creek. But unlike a swimming beach at a reservoir or other body of water, local officials have little ability to restrict human access to a stream like Boulder Creek, Wilson said…

…earlier in the week, Dickson did offer a response to Boulder Waterkeeper data the advocacy group used to assert there is a that there is a “human waste footprint” to the detected E. coli.

E. coli is a bacterial marker for fecal pollution, which lives in the intestines of humans, wildlife, cattle and dogs, but is not always harmful to humans. However, one strand, known as 0157:H7, can cause abdominal cramps, diarrhea, vomiting and even life-threatening conditions…

“The one sample taken does not provide conclusive evidence that human source bacteria were present. The strain of bacteria the lab tested for could also come from other animals, such as raccoons and geese. Again, the lab indicated more data is needed to determine whether the strain is from humans versus other animals. At this time, even with these E.coli and human fecal bacterial levels, there is no indicator of an illicit discharge or other noncompliance with the university’s permit.”

Colorado re-mapping floodplains of most-affected waterways — TheDenverChannel.com

Flooding in Longmont September 14, 2013 via the Longmont Times-Call

From TheDenverChannel.com (Deb Stanley):

After the 2013 floods devastated communities and took several lives, the state of Colorado is remapping the regulatory floodplain of the most affected waterways in Colorado.

“It’s important to provide public and local land use managers with the most accurate flood risk information so they can make better decisions,’ explained Thuy Patton, Flood Mapping Program Manager for the Colorado Water Conservation Board.

In some counties, there are areas that now have higher flood risk and other areas that now have lower flood risk, which changes which homes are in the flood plain. NOTE: these numbers are approximate, based on public information, and are subject to change.

In Boulder County, with this update, 420 new structures are in flood risk area and approx. 400 structures are now not in special flood hazard area, Patton explained.

In Jefferson County, 53 structures were added.

In Larimer County, 601 structures were added and 1,571 were removed.

In Weld County, 453 structures were added and 1,994 were removed.

In Sedgwick County, 85 structures were added and two were removed.

In Washington County, 26 structures were added and 31 were removed.

In Morgan County, 38 structures were added and four were removed.

And in Logan County, 222 structures were added, while 59 were removed.

FEMA uses Flood Insurance Rate Maps (FIRMs) to set flood insurance premiums. The Preliminary FIRMs will become FEMA’s final effective FIRMs in 2021, pending any appeals received by FEMA.

Learn more about the mapping project here.

Boulder County is starting a series of public meetings about the changes. Representatives from FEMA, the mapping team, and Boulder County will be present at each session. Each open house will focus on specific reaches, but residents are invited to discuss any stream at each meeting:

  • Lower Boulder Creek, New Dry Creek, Coal Creek, and Rock Creek – Tuesday, Jan. 14 | 5 to 6:30 p.m. (presentation at 5:15 p.m.) Boulder County Recycling Center – 1901 63rd Street in Boulder County
  • Saint Vrain Creek, Lower Left Hand Creek, Dry Creek #2, and Little Thompson River – Thursday, Jan. 16 | 5 to 6:30 p.m. (presentation at 5:15 p.m.) Boulder County Parks and Open Space Ron Stewart Building – 5201 St. Vrain Drive in Longmont
  • North, Middle, and South Saint Vrain creeks and Cabin Creek – Tuesday, Jan. 21 | 5 to 6:30 p.m. (presentation at 5:15 p.m.) Highlands Presbyterian Church – 1306 Business Highway 7 in Allenspark
  • Little James Creek, James Creek, Upper Left Hand Creek, and Geer Canyon – Tuesday, Jan. 28 | 5 to 6:30 p.m. (presentation at 5:15 p.m.) Jamestown Town Hall – 118 Main St. in Jamestown. This is a joint meeting between Boulder County and the Town of Jamestown
  • Fourmile Canyon Creek, Two Mile Canyon Creek, Gold Run, Fourmile Creek, Boulder Creek and North, Middle, and South Boulder creeks – Thursday, Jan. 30 | 5 to 6:30 p.m. (presentation at 5:15 p.m.). Boulder Public Library Main Branch, Boulder Creek Room – 1001 Arapahoe Ave. in Boulder
  • Boulder District Judge Andrew Macdonald affirms Boulder County’s 1041 oversight for @DenverWater’s Gross Reservoir Expansion Project

    The dam that forms Gross Reservoir. Photo: Brent Gardner-Smith/Aspen Journalism

    From The Boulder Daily Camera (Charlie Brennan):

    In a seven-page ruling, Boulder District Judge Andrew Macdonald stated that based on evidence placed on the record by both sides in the controversy, he found Boulder County “did not exceed its jurisdiction or abuse its discretion, or misinterpret or misapply the law,” when it asserted its permitting authority.

    That authority, Boulder County has maintained, is established by State House Bill 1041, passed by the Legislature in 1974, which allows local governments to review and regulate matters of statewide interest through a local permitting process.

    Denver Water challenged that authority by filing suit in Boulder District Court in April of this year, claiming what it termed a “zoned law exemption” which it asserted excused it from having to pass through the county process. Denver Water’s complaint claimed the zoning at the reservoir that existed at the time of the passage of the 1041 legislation — officially known as the Activities and Areas of State Interest Act — permitted its planned activities.

    Additionally, the suit stated Boulder County commissioners had exceeded their jurisdiction and/or abused their discretion at a March 14 hearing at which they unanimously upheld Land Use Director Dale Case’s finding that the county review process must apply to Denver Water.

    Macdonald’s ruling struck down Denver Water’s claim to an exemption based on prior zoning.

    “There is nothing on the record that Denver Water had any well-established development rights to expand Gross Dam and Gross Reservoir prior to May 17, 1974,” he ruled. “Any prior contemplated expansion projects cannot be determined to be well-established development rights because the proposed Expansion Project is essentially an entirely new construction project.”

    […]

    In an email Friday night, Denver Water spokesman Travis Thompson said, “As we continue to follow the process of determining the appropriate permitting methods, we will review the order and evaluate our next steps. No matter the path forward, we remain committed to considering input from Boulder County and from community members to minimize and mitigate the impacts of the Project.”

    An additional hurdle remains for the project. Denver Water is still waiting for a final decision by the Federal Energy Regulatory Commission on a hydropower licensing amendment that Denver Water needs in order to go forward with its planned expansion of the reservoir.

    Denver Water’s collection system via the USACE EIS

    Raising a Dam — @ColoradoStateU

    Here’s the release from Colorado State University (Anne Manning):

    Gross Dam spillway design being put to the test by CSU civil engineers

    On any given day, the roar of water cascading over a 20-foot-high dam spillway greets visitors to Colorado State University’s Hydraulics Laboratory. Muck boots are required footwear, as water from the spray spreads across the floor, drains into an under-floor reservoir, and flows back toward an outtake pipe for recycling.

    The experimental spillway, constructed by CSU civil engineers, is a test bed for an ambitious dam-raising project in southwest Boulder County by Denver Water. CSU engineers are applying their hydraulics expertise to help verify key design and functionality aspects of the spillway, part of the public utility’s planned upgrade to Gross Dam. The reservoir impounded by Gross Dam provides water to more than 1.4 million residents along Colorado’s Front Range.

    The engineering team designing the project for Denver Water, Stantec and primary subcontractor AECOM, commissioned civil engineering professors Chris Thornton and Rob Ettema to create a 1:24 working scale model of the heightened dam’s new spillway. The spillway is the only portion of the dam over which water passes.

    A project of this magnitude requires a physical hydraulic model, Thornton said.

    “Computers have come a long way, but they’re not even close to being able to resolve what’s happening in terms of interaction of forces,” Thornton said. “Turbulence and air entrainment are very hard to model accurately.”

    Stepped spillway

    Taylor Hogan, a civil engineering master’s student and Hydraulics Laboratory manger, led the design and building of the model, which required close to 500 custom-built pieces. It is called a stepped spillway, which dissipates energy from the water as it flows over the dam. The steps slow the water, trap air bubbles, and allow water to safely descend. Adding to the model construction’s complexity is a slight arch to the spillway profile – mimicking the current profile.

    The CSU engineers are now testing and documenting performance, including capacity, flow rate, and ability to handle a major influx of water from a storm or natural disaster. When complete, Gross Dam’s will be the tallest stepped spillway in the United States.

    The planned height of the dam necessitated the stepped design. The dam is slated to be raised 131 feet over its current height of 340 feet, increasing the capacity of Gross Reservoir by about 25 billion gallons.

    “The expansion will allow Denver Water to add balance and resiliency to its water collection system, which today is at risk of damage from natural disasters such as wildfires and floods,” said Jeff Martin, Denver Water’s Gross Reservoir Expansion Project program manager. “It will also help to manage the greater uncertainty that comes with a changing climate.”

    The Stantec/AECOM team specified that the spillway be able to manage extreme high flows they estimate to be possible during the rare occurrence of a massive storm.

    “The spillway is designed very conservatively and must perform safely when exposed to extreme conditions,” Ettema said.

    Engineering students Taylor Hogan and Blake Biethman stand next to the Gross Reservoir expansion stepped spillway model, Sept. 9, 2019. Photo credit: CSU/Bill Cotton

    Remaining work

    The CSU researchers are wrapping up the modeling work for Stantec/AECOM to complete the spillway design. The remaining work includes optimizing the layout of the energy-dissipation basin at the bottom of the spillway, to ensure Gross Dam’s design meets safety requirements. Design engineering on the overall dam project is expected to extend through the end of 2020.

    Water flows through the distilling basin at the bottom of the spillway model. Photo credit: CSU/Bill Cotton
    Gross Reservoir in the mountains to the southwest of Boulder. Denver Water hopes to increase the height of the dam 131 feet, to a new height of 471 feet, to store three times as much water, which it says will help it meet increasing demands and to better weather severe droughts.

    Gross Reservoir Expansion Project update

    Gross Dam enlargement concept graphic via Denver Water

    From TheDenverChannel.com (Jace Larson):

    The project will require significant construction over seven years to increase the reservoir’s holding capacity to 119,000 acre-feet of water.

    When built, the dam will be the tallest in Colorado.

    Denver Water says the additional space is needed to spread out capacity outside of Denver for the water utility used by 1.4 million people in the city and its surrounding suburbs.

    The proposed construction project is not without opposition from neighbors and environmentalists who say they will endure years of construction on a water project that will never provide water to their taps.

    “Boulder County is going to host this reservoir but gets no water from it. We derive no benefit from it. We only pay the price of having this thing in our county,” said Tim Guenthner, who lives just above the dam in a subdivision of about 1,000 people.

    Denver7 decided to take a 360 look at this issue and gathered perspectives from five people connected to the proposed construction project…

    Boulder County Commissioners have also taken a stance that Denver Water must get local permits before it can start the project.

    Denver Water spokesman Travis Thompson said Denver Water doesn’t believe the law requires that and points out it has undergone numerous environmental studies and worked through the state permit process. This issue will likely be decided by another judge…

    Denver Water’s Gross Dam project manager, Jeff Martin, acknowledges the project will cause noise for neighbors.

    “Well we don’t hide from the fact there’s going to be some disruption from the noise, but we are looking at ways of minimizing that noise,” Martin said.

    As an example, Denver Water decided to move the quarry needed to make cement to a portion of the lake that will be covered by water once more capacity is added. The original plan had the quarry on a portion of land jetting out into the lake.

    Have an on-site quarry will also mean less truck traffic.

    Martin said even with conservation efforts, Denver Water needs more capacity. He said experts have provided the water utility with data showing there will be 5 million more people in Colorado by 2050.

    Denver water has 90% of its storage lakes west and south of the metro area, but only has 10% up north. This new dam project will add significantly more water storage north of the city.

    “That’s important because if we have a catastrophic event or a drought in one of the systems, it leaves us depending on the other system,” he said. “What we want to do is create a little bit more balance and put more water in Gross Reservoir. This project is going to triple the size of the reservoir.”

    […]

    Kirk Klanke is a member of Trout Unlimited, an environmental group seeking to protect and restore rivers across the country.

    His perspective is one many wouldn’t expect from a member of the environmental group. He’s a supporter of the new dam.

    “I think it’s extremely selfish to think we shouldn’t grow,” he said.

    He says Denver Water has the legal right to build more capacity someplace. Gross Reservoir is the best option.

    “Raising an existing dam has far less environmental damage than building a new one somewhere else,” Klanke said.

    He says Denver Water has agreed to put significant effort into protecting the Colorado River. When it is hot out, river temperatures rise if there’s only a little water flowing.

    Denver Water has agreed to keep water in the river during those periods and fill the lake during spring runoff. It will also draw water at different places in the river to minimize the impact to one area.

    Gross Reservoir. Photo: Brent Gardner-Smith/Aspen Journalism

    @DenverWater hires contractor for Gross Reservoir Expansion Project

    The Gross Reservoir Expansion Project will add 77,000 total acre feet — 72,000 for Denver Water use and 5,000 for an environmental pool that provides additional water for South Boulder Creek during low-flow periods — nearly tripling reservoir capacity.

    From Denver Water:

    Denver Water’s five-member Board of Water Commissioners on Wednesday approved a two-year, $4.5 million contract with Kiewit Barnard, a Joint Venture, for planning and pre-construction work during the final design phase of the $464 million Gross Reservoir Expansion Project.

    If the team’s performance during the planning and pre-construction phase meets Denver Water’s expectations, a separate contract to build the dam may be signed between Denver Water and Kiewit Barnard.

    “This is a major milestone in our 16-year effort to expand Gross Reservoir, as its original designers intended decades ago, to ensure a more reliable water supply in a future marked by greater uncertainty in weather patterns,” said Denver Water CEO/Manager Jim Lochhead.

    Denver Water, the state’s largest water utility, serves 1.4 million people in Denver and surrounding suburbs.

    Gross Dam enlargement concept graphic via Denver Water

    The Gross Reservoir Expansion Project will raise the height of the existing dam, completed in 1954, by 131 feet, allowing the reservoir to nearly triple in size. When complete, the reservoir will be capable of holding about 119,000 acre-feet of water to provide greater system balance and resiliency.

    The selection process for a construction manager/general contractor for the project began in August 2018 with information meetings, followed by a formal Request for Qualifications in October 2018. Three teams responded to the request and underwent extensive evaluations and interviews by a selection team that included experts from Denver Water, the project’s design engineer and subject matter experts.

    The selection team focused on a value-based competitive process that examined each team’s qualifications, project approach, technical approach and cost.

    “Kiewit Barnard met Denver Water’s high bar for doing a project that’s important not only to the 1.4 million people who rely on us for their drinking water, but also to the people who live around the reservoir,” said Jeff Martin, Denver Water’s program manager for the expansion project.

    “We were impressed by the team’s experience with roller-compacted concrete dam construction, innovative approach and commitment to safe and responsible building practices,” Martin said.

    The project calls for adding 900,000 cubic feet of concrete to the existing structure and building the first roller-compacted, concrete, arch dam in the United States. When complete, the Gross Dam will be the tallest in Colorado and the tallest roller-compacted concrete dam in the U.S.

    “Kiewit Barnard, a Joint Venture, is very pleased to have been selected to work on this important project to support water demand for the greater Denver area,” said Jamie Wisenbaker, senior vice president of Kiewit Infrastructure Co., and an executive sponsor of the project. “We believe the team’s collective infrastructure experience in dam and reservoir construction and engineering will be a huge asset and look forward to safely delivering a high-quality project on time for Denver Water and the region.”

    Kiewit is one of North America’s largest construction and engineering organizations with extensive heavy-civil experience in water/wastewater construction, including serving as lead contractor on the Oroville Spillways Emergency Recovery project in California. Kiewit is the No. 1 contractor for dams and reservoirs in the United States according to Engineering News-Record. The company also has strong roots and experience in Denver and across Colorado, including having constructed the Interstate 25 T-REX Expansion project, the U.S. 34 Big Thompson Canyon emergency repair project and the I-225 Light Rail Line project. The company also is building Denver Water’s new Northwater Treatment Plant.

    Barnard Construction Co. Inc. brings a long track record of safety and quality on infrastructure projects in the U.S., including construction on more than 80 dams, reservoirs and dikes over the last four decades. The company’s work in this area includes new construction, raising dams and conducting emergency repairs. In 2019, Barnard was honored as a “Global Best Project” award winner by Engineering News-Record in the dam/environment category for the Muskrat Falls North and South Dams project located in Muskrat Falls, Newfoundland and Labrador, Canada.

    The Gross Reservoir Expansion Project is awaiting a final federal government approval from the Federal Energy Regulatory Commission. Provided the remaining federal approvals come by the end of this year, the project is slated to be complete in 2025.

    When finished, the expanded reservoir and associated mitigation projects will create what the Colorado Department of Public Health and Environment has described as a net environmental benefit to state water quality by generating a wide range of environmental improvements to streams, river flows and aquatic habitats.

    #Runoff news: #ClearCreek tubing and swimming ban lifted, #Boulder #TubeToWorkDay now scheduled for July 19, 2019

    From The Denver Post (Kirk Mitchell):

    Belly boaters, swimmers, inner-tubers and body surfers take note: You can now do your thing on Clear Creek in Jefferson County.

    The Jefferson County Sheriff’s Office has removed its ban on water activities that had been considered too dangerous on July 1 because of fast water flows.

    The ban – which had extended from State Highway 119 to Golden – has been lifted for swimmers and those using all single-chambered air inflated devices including belly boats, inner tubes and rafts, said a sheriff’s office news release Friday.

    From Westword (Michael Roberts):

    Today, July 12, the Jefferson County Sheriff’s Office ended all restrictions for activities on Clear Creek, including limits put in place through Golden circa July 1. Likewise, the Boulder Police Department has removed a tubing ban on Boulder Creek, which resulted in the postponement of the city’s annual Tube to Work Day…

    By the way, Boulder’s Tube to Work Day is now scheduled to get underway at 8 a.m. on Friday, July 19. Life jackets and wetsuits are strongly recommended to be worn beneath business attire, and mandatory items include helmets, closed-toe footwear and waivers.

    From The Aspen Times (Jason Auslander):

    With the North Star Nature Preserve flooded and space dwindling under bridges, county open space officials are asking boaters to put in at the popular float spot’s midway point until further notice.

    “We’re encouraging everybody across the board … to put in at Southgate,” Pryce Hadley, ranger supervisor for the Pitkin County Open Space and Trails program, said Monday. “The water is high for July and people need to be careful.”

    […]

    The lack of Front Range diversions adds about 550 cubic feet per second to the Roaring Fork River, they said. That water began flowing down the Roaring Fork on Thursday evening, and the river peaked at just over 1,000 cfs July 6, Hadley said. It was running at 779 cfs Monday morning, he said…

    “That’s still well above the 300 cfs we had midday on July 4,” Hadley said.

    And that means boaters who begin at the normal North Star put-in at Wildwood are not going to be able to make it under a pedestrian bridge and a car bridge at McFarland Gulch, he said. While some stand-up paddlers might be able to make it under the bridges lying on their bellies face down, most likely cannot, Hadley said.

    Portage is not possible either, he said, because the bridges and surrounding land are on private property, he said.