Gross Reservoir Expansion Project

The Big Picture

Denver Water didn’t learn anything from the Environmental Protection Agency’s veto of the Two Forks Dam project in 1990.

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Fiction.

We learned a lot, actually, which has informed our plans and actions ever since, and led to our industry-leading and nationally-recognized conservation program, pioneering the use of recycled water, and responsibly sourcing additional supply.

Failing on Two Forks was an inflection point; one where we made the conscious decision to listen more. Listening is, in part, how we arrived at expanding Gross Reservoir, as environmental groups who opposed Two Forks recommended raising Gross Dam as an alternative. The fact that Gross Reservoir was designed from the beginning for two subsequent dam raises was a contributing factor in it being selected as the preferred alternative over more than 30 that were considered.

An expanded Gross Reservoir will never fill because – according to climate models – there won’t be enough water in key West Slope watersheds.

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Fiction.

This myth is supported by an analysis that uses a different time period, different assumptions, different data and a different model than the hydrologic analysis conducted by independent experts that was published in the Army Corps of Engineers’ Environmental Impact Statement (EIS). The flawed methodology used by opponents invariably produces results that differ from the model adopted by those with competing water interests on both sides of the continental divide. Further, the Corps found opponents’ attempts to compare results were inaccurate and misleading. (Source: Corps FEIS, Attachment B, Page 17)

The only certainty is an uncertain future and the Gross Project will allow us to better adapt and provides greater flexibility than our current situation.

Just like they did on the Two Forks Project in 1990, the Environmental Protection Agency (EPA) will veto and stop this project.

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Fiction.

In this June 2017 letter to the U.S. Army Corps of Engineers, the EPA’s Acting Regional Administrator states explicitly:
  • The EPA compliments the Corps’ team for addressing all of the EPA’s comments in a professional and efficient manner
  • The EPA will not (emphasis ours) be requesting a higher level of review of the Corps’ decision
  • That diversions of West Slope water to the Front Range will not (emphasis ours) result in significant degradation of West Slope watersheds

There is an active fault located beneath the reservoir.

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Fact AND Fiction.

There are faults beneath Gross Reservoir, but they are not active and do not pose an earthquake threat. Chapter 5, page 5-204 of the Final Environmental Impact Statement reads “…the Livingston Sheer Zone and Fault, the Copeland Fault, and the Rogers Fault are not mapped as potentially active and therefore unlikely to create earthquake activity near Gross Reservoir.” Faults that have been identified in the vicinity of the dam have been deemed inactive so there is little chance that the activation of theses faults is possible. Nonetheless, Denver Water will conduct detailed geotechnical and seismic studies in the design and construction phases of the project.

Denver Water customers need to conserve more.

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Fact.

We wholeheartedly agree with that statement, which is why we continue our industry-leading and nationally-recognized conservation program. The reality of the situation – as it relates to expanding Gross Reservoir – is we can’t simply conserve our way to a secure water future. Our “all of the above” approach includes promoting use of recycled water, driving conservation, and responsibly sourcing additional supply – which includes expanding Gross Reservoir.

Since its design in the early 1950s, Gross Dam was always intended to be raised.

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Fact.

Denver Water archives show Gross Dam was always intended for two subsequent dam raises. Current plans call for these to be completed in one so the full storage capacity of Gross Reservoir can be realized.

Denver Water should make plans with the goal of limiting growth.

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Fiction.

Denver Water doesn’t have the authority to control or manage growth. It is our job to plan for future needs of our customers, so we rely on outside experts (such as DRCOG) to provide population estimates and plan accordingly.

Additional water taken by an expanded Gross Reservoir will cause our state to default on our obligations under the Colorado River Compact Agreement.

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Fiction.

The expected yield to be stored in an expanded Gross Reservoir will not impact our ability to fulfill our obligations. Besides, if the small amount of yield this project plans to gain from the Fraser River during future wet years were of concern to downstream users and threatened compact obligations, why have no objections been raised by those with legal standing during the 14-year period the project has been in the planning and permitting stages?

Denver Water doesn’t have the ability to treat all the water they plan to collect and store in an expanded Gross Reservoir.

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Fiction.

Our water treatment facilities currently have the capacity to treat water to meet needs of our customers into the future. Also, we are in the design phase of the new Northwater treatment plant as part of our larger North System Renewal Program, which will provide up to 150 million gallons of water per day for our customers.

Environmental

Denver Water is increasing the size of the National Forest System.

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Fact.

Denver Water will convey approximately 540 acres of land near the Moffat Tunnel, which includes forest, riparian, and wetland habitats, to the United States Forest Service for permanent protection and management as part of the National Forest System (NFS). This land conveyance represents mitigation for impacts to approximately 280 acres of NFS land that will be inundated by the Gross Reservoir expansion. Stated simply, Denver Water will provide nearly a 2:1 mitigation ratio of replacement acreage transferred to the U.S. Forest Service to offset those acres of NFS land that will be lost due to the expanded reservoir footprint.

There’s a geologic fault line that runs beneath Gross Dam and that fault will become active when the height and mass of the dam is increased.

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Fact AND Fiction.

There are faults beneath Gross Reservoir, but they are not active and do not pose an earthquake threat. Chapter 5, page 5-204 of the Final Environmental Impact Statement reads “…the Livingston Sheer Zone and Fault, the Copeland Fault, and the Rogers Fault are not mapped as potentially active and therefore unlikely to create earthquake activity near Gross Reservoir.” Faults that have been identified in the vicinity of the dam have been deemed inactive so there is little chance that the activation of theses faults is possible. Nonetheless, Denver Water will conduct detailed geotechnical and seismic studies in the design and construction phases of the project.

The project hasn’t adequately studied impacts to Walker Ranch Open Space.

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Fiction.

This issue was studied thoroughly and there will be no direct impacts to the Walker Ranch Open Space or any other Boulder County Open Space land ( Final Environmental Impact Statement, Chapter 5, page 5-450.). However, there will be short-term, indirect effects to users of Walker Ranch due to noise and visual effects of the construction activities. In addition, Per the Final Environmental Impact Statement, Chapter 5, page 5-290, “The Hawkin Gulch/Walker Ranch/Upper Eldorado Canyon Environmental Conservation Area (ECA), located below the dam, would not incur impact under the Proposed Action or any other action alternatives.”

Permitting authorities must select the Least Environmentally Damaging Practicable Alternative (LEDPA).

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Fact.

Expanding Gross Reservoir is the Least Environmentally Damaging Practicable Alternative (LEDPA). According to page 15 of the US Army Corps of Engineers’ Record of Decision, “The Section 404(b)(1) Guidelines require the Corps to identify the (LEDPA). The Corps has identified (Denver Water’s) Preferred Alternative, including the Environmental Pool, as the LEDPA. The Corps LEDPA determination would not change if the Environmental Pool was not included in the construction and operation of (Denver Water’s) Preferred Alternative.” Denver Water has committed more than $20 million to more than 60 different environmental projects on both sides of the divide that will be carried out as components of the Gross Reservoir Expansion project. According to the state of Colorado, those commitments will have a net environmental benefit for our state.

An expanded Gross Reservoir will destroy the environment.

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Fiction.

We have worked very hard to avoid that. The State of Colorado has studied the likely impacts, compared these with the mitigation and enhancements we have committed to as conditions of various agreements and permits, and found the project will have a "net environmental benefit" for Colorado. That is one of many reasons why the project is endorsed by Gov. Hickenlooper and the last four governors of our state, along withstate and federal lawmakers, major environmental groups, local mayors and city councils, chambers of commerce and economic development corporations, county elected officials and water interests on both sides of the divide.

A taller dam will damage aquatic conditions in South Boulder Creek

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Fiction.

Environmental studies show that water temperature at the reservoir outflow is generally in the acceptable range for trout today, and will be similar in the future once the expansion is completed.

Currently, the biggest threat to aquatic life in South Boulder Creek is lack of water, not water temperatures. As it stands today, there are times of the year when some portions of SBC run at water levels insufficient to maintain aquatic life. An expanded Gross Reservoir will include space for an environmental pool, which will be managed by the cities of Boulder and Lafayette. The intent of this is to enable release of water during low flow periods so SBC will have life sustaining flows year-round.

Learn more here.

Noise from the project will not exceed Boulder County noise standards.

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Fact.

Denver Water is committed to monitoring noise impacts and conforming to all applicable local codes and regulations. The noise study, performed by independent experts, finds all work can be completed without exceeding noise standards set by local authorities. We will work with neighbors and use best management practices and mitigation technologies to reduce noise impacts to the greatest extent possible.

650,000 trees will be removed to make way for this project.

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Fact AND Fiction.

Trees will need to be removed to expand Gross Reservoir, though the figure is likely far less than 650,000 according to Boulder District Forester Allen Owen. He told the Daily Camera that “the number seems high". Denver Water uses this most conservative, worst-case scenario because we want to work in good faith and be transparent. The loss of these trees is considered and accounted for in the multi-year environmental review and permitting processes this project has required.

Removal techniques and the final plan will be studied more thoroughly in the coming years and will include public input to minimize inconvenience. New environmentally friendly disposal technologies that didn’t exist when the initial plan was developed will be evaluated and pursued if found to be beneficial. If hauling is required, trucks hauling materials will use the same route – albeit in reverse – as those hauling materials to the site. In other words, we will use Gross Dam Road and State Highway 72; we will NOT use Flagstaff Road or transport through Boulder.

Construction

Haul trucks on Highway 72 will make it unsafe.

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Fiction.

All vehicles serving the project will be certified by the state as safe to operate, and drivers will be required to pass a project-specific safe driving course before they are allowed to haul their first load for the project. We’ll also require the use of dash cameras in all trucks and will perform random, surprise spot checks of their drives to make sure they are operating safely. Finally, we will be funding increased traffic patrols by Boulder and Jefferson County Sheriff’s Offices to improve safety for all who use Highway 72.

Trucks in the canyon are going to make my commute miserable.

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Fiction.

We’ve run the numbers and can avoid typical morning and evening commutes if that is something the community would prefer. We’ve also committed to not haul during hours students are being bused to- and from-school.

Highway 72 is not capable of handling the hauling traffic.

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Fiction.

We’ve met with Colorado Department of Transportation representatives who stated that Highway 72 is rated for tractor-trailer haul trucks and is capable of handling the increased traffic. We also performed a real-world study and found fully-loaded haul trucks were able to maintain posted speed limits within the canyon through the end of the haul route at Gross Dam. See the “Construction Traffic Documents” entry and videos documenting the study here.

Noise from the project will not exceed Boulder County noise standards.

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Fact.

Denver Water is committed to monitoring noise impacts and conforming to all applicable local codes and regulations. The noise study, performed by independent experts, finds all work can be completed without exceeding noise standards set by local authorities. We will work with neighbors and use best management practices and mitigation technologies to reduce noise impacts to the greatest extent possible.

Denver Water will keep Gross Dam Road in good condition throughout construction.

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Fact.

Currently, Boulder County maintains Gross Dam Road from Highway 72 to the railroad tracks and Denver Water maintains the road from the tracks through to Flagstaff Road. If allowed by Boulder County, during construction Denver Water will maintain the entirety of Gross Dam Road from Highway 72 to Flagstaff Road. It’s critical that we ensure efficient transfer of construction-related materials, so it is in our interest for this road to be in excellent condition. Maintenance operations will include regular grading, placement of environmentally friendly road stabilizing materials and frequent treatment to mitigate against dust.

Denver Water’s hauling plans provide no meaningful mitigation.

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Fiction.

Based on community input, we’ve found ways to reduce by 75 percent the number of truck trips required for hauling materials by producing all the required aggregate from an on-site quarry. We’ve committed to not haul on Highway 72 while students are being bused, or during common morning and evening commute times. All trucks and operators will be properly licensed by the state and all drivers will pass a project-specific safe driving course prior to hauling their first load. The latest technology will be used to monitor truck speeds and dash video cameras will be mandatory to record driver behavior and professionalism.

Commuter traffic all across Boulder County and City of Boulder will increase during construction.

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Fiction.

The primary access route to the site will be via Highway 72 to Gross Dam Road. Denver Water is considering plans to encourage carpooling, use an employee shuttle, etc. We’re also collecting public input to gather preferences about limiting materials hauling to certain days of the week and specific windows of time. Hauling will not take place on Highway 72 when students are being bused, during typical morning and evening commutes, and the designated haul route does not go through the City of Boulder or use Flagstaff Road.

The project will increase light pollution both short-term and permanent impacts

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Fact AND Fiction.

During construction, lighting will be required to perform nighttime operations safely and in conformance with OSHA standards. These lights will be downcast to minimize the impact to the community, and removed at the end of construction. Denver Water has no plans to increase amount of lighting of the completed facility beyond what exists today.

The project hasn’t adequately studied impacts to Walker Ranch Open Space.

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Fiction.

This issue was studied thoroughly and there will be no direct impacts to the Walker Ranch Open Space or any other Boulder County Open Space land ( Final Environmental Impact Statement, Chapter 5, page 5-450.). However, there will be short-term, indirect effects to users of Walker Ranch due to noise and visual effects of the construction activities. In addition, Per the Final Environmental Impact Statement, Chapter 5, page 5-290, “The Hawkin Gulch/Walker Ranch/Upper Eldorado Canyon Environmental Conservation Area, located below the dam, would not incur impact under the Proposed Action or any other action alternatives.”

Property owners and residents who will be most impacted will not see a benefit of the project.

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Fact.

There’s no sense denying that because we do not serve water to the communities around Gross Reservoir, they will not see a direct benefit of greater storage. There will be short-term impacts to local residents. That’s one reason why we’re working so hard to make commitments and concessions to reduce the impact of the project on the local community. However, Gross Reservoir is a tremendous recreational amenity to those in the area and will continue to be so during and after construction.

Hauling over Crescent Park Drive will create an unsafe condition.

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Fact.

That’s why we’ve committed to NOT use Crescent Park Drive for materials hauling or transport of construction equipment, and the same goes for Flagstaff Road. Materials and construction equipment will be delivered to the site via Highway 72, with flaggers in place at the intersection of Highway 72 and Gross Dam Road. They’ll also be in place at other critical spots along Gross Dam Road where there are tight turning radiuses and points of limited visibility.

Denver Water has guaranteed access to Gross Dam Road.

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Fact.

Safety is our number one priority, and Denver Water is committed to maintaining public access to Gross Dam Road from Highway 72 through to Flagstaff Road throughout construction. Flaggers may be used at key points (narrow points, blind curves) during materials hauling to ensure safety. In times of emergency, we will fully cooperate with, enable and assist first responders as needed.

Trucks in the canyon are going to make it unsafe for children on school buses.

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Fiction.

We’re committed to avoiding hauling during periods when children are riding on school buses.

The semi-trucks Denver Water used in its hauling study were empty, calling into question whether trucks to be used during construction will be able to maintain speed in the canyon.

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Fiction.

We used a total of 10 trucks in our hauling study – the first five we sent up the hill were fully loaded to mimic the real-world hauling scenario. The study found that fully-loaded trucks of the type we plan to use will be able to maintain posted speeds in the canyon, make all the turns on the haul route safely, etc. More information about our hauling study can be found here under the drop-down in construction traffic documents.

Latest News / Blog

Project related activities

April 18, 2019 – Denver Water will have contractor crews at the intersection of State Highway 72 and Gross Dam Road on Friday, April 19 performing geotechnical investigation activities. This work is necessary for the design of safety related roadway improvements for...

A statement from the CEO/Manager

Below is a statement from Denver Water CEO/Manager Jim Lochhead regarding the April 11 complaint filed in District Court on the zoned land use exemption: Our commitment to the community has been demonstrated from the beginning when we intentionally and explicitly...

Collaboration works for 21st century Denver Water

Colorado Central Magazine - April 1, 2019 - "Commissioners from Grand County showed up at a noisy Boulder County commissioners’ hearing on a West Slope-to-East Slope transmountain water diversion project – to testify on behalf of the project." Read the full story...

Leaning In To The Challenge Of Climate Change

Water Online - April 2, 2019 - "Under the Colorado River Cooperative Agreement, the flexibility that comes with more storage in Gross also ensures Denver Water can support stream flows in the Fraser River and other high elevation West Slope streams in drier years..."...

When east meets west over water resources

Winter Park Times - March 14, 2019 - "The goal of Learning By Doing is to restore or enhance the condition of the river health in Grand County through projects and improved communication between the partners. LBD is not supposed to be effective until permits for...