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Top Ten fatal flaws with Moffat/Gross

You can read TEG's entire 104-page FEIS Comment Letter here.

Click on an issue to see more details.

#1 - The stated “purpose and need” of the project is invalid.

The Environmental Impact Statement states the “purpose and need” of the project as: The purpose of the Moffat Collection System Project is to develop 18,000 acre-feet per year of new, firm yield to the Moffat Treatment Plant and raw water customers upstream of the Moffat Treatment Plant pursuant to the Board of Water Commissioners’ commitment to its customers.1

Because project alternatives are based on the “purpose and need” statement, agencies cannot define the purpose and need of a project “so narrowly as to preclude a reasonable consideration of alternatives.”2

The stated purpose of the project in the Environmental Impact Statement is so narrow that it precludes all alternatives other than the expansion of Gross Reservoir plus additional trans-basin diversions from the Upper Colorado Basin.


1: Moffat Collection System Project - Final Environmental Impact Statement, ES-6 Executive Summary, page 10, published April 2014.

2: Wyoming v U.S. Dept. of Agric., 661 F.3d 1209, 1244 (10th Cir. 2011) (quoting Citizens’ Comm. to Save Our Canyons v I.S. Forest Serv., 297 F.3d 1012, 1030 (10th Cir. 2002)); see also Nat’l Parks & Conservation Ass’n v. Bureau of Land Mgnt., 606 F.3d 1058, 1072 (9th Cir. 2009) (agency cannot “craft a purpose and need statement so narrowly drawn as to foreordain approval of the [proposed project]”); Simmons v. U.S. Army Corps of Eng’rs, 120 F.3d 664, 666 (7th Cir. 1997) (“If the agency constricts the definition of the project’s purpose and thereby excludes what truly are reasonable alternatives, the IES cannot fulfill its role”).

#2 - Expanding Gross Reservoir as the “preferred alternative” does not fulfil the stated “purpose and need”.

The stated purpose of the Moffat-Gross project as described in the Environmental Impact Statement - to obtain an additional 18,000 Acre-Feet per Year of firm yield for Denver Water - would not met with the "preferred alternative".

Because actual firm yield for the project is not discussed in the Environmental Impact Statement, and because stream flows in the Fraser Basin are already severely depleted, an independent analysis of the firm yield of the expanded reservoir combined with the remaining water supply in the Fraser and Williams Fork basins was undertaken.1 Results of this analysis indicate that the stated 18,000 AFY firm yield requirement for the proposed project, expansion of Gross Reservoir to almost three times its current volume, cannot be met under both the “current” and “full use” Environmental Impact Statement baseline model scenarios:

Including storage in the expanded portion of Gross Reservoir and all estimated basin excess flows, the reservoir would fill in only 3 years out of 44<./p>

The percentage of years where the firm yield of 18,000 AF/YR was NOT met substantially exceeds the EIS alternative screening criteria of greater than one in four years, or 25 percent.

In fact, it would require 4,000 AFY more than all the calculated excess basin flows (15,557 AFY) to achieve the 18,000 AFY firm yield required by the proposed project at the frequency required by the screening criteria detailed in the Environmental Impact Statement.


1: Buchanan, 2014

#3 - Half of Denver Water’s residential water goes onto lawns while a large percentage of Coloradans live happily without any outdoor water usage.

48% of Denver Water’s total retail treated water is used by single-family homes. The average single-family residential customer uses 50 percent of their water for outdoor use. This totals roughly 60,000 acre-feet annually. That’s 333% the volume of water that the Moffat Collection System would potentially yield.1

Meanwhile, a large percentage of Colorado residents, sourcing their water from groundwater wells, are prohibited from outdoor water usage: “Ground water wells are the principle source of water for most homeowners in rural areas of Colorado. There are over 200,000 permits for ground water wells currently issued in our state and approximately 4,000 new permits are requested annually. Most of these wells are used for households and are considered “exempt” from the administration within the water rights priority system. They require a permit from the State Engineer, and are limited to 15 gallons of water per minute. Some exempt wells are further limited to in-house use only when lot sizes are smaller than 35 acres.”2

Spending hundreds of millions of dollars and further damaging Western Slope ecosystems and economies in the name of securing more water for non-native lawns in a semi-arid climate may not be the most appropriate allocation of limited resources.


1: Water Use - Denver Water - http://denverwater.org/SupplyPlanning/WaterUse

2: Private Wells for Home Use, E. Marx, R. Waskom and D. Wolf3

#4 - The Environmental Impact Statement fails to address the impacts of what would be the largest construction project in Boulder County history.

During a two-date public hearing (December 20, 2012 and January 7, 2013) the Boulder County Commissioners considered a draft Intergovernmental Agreement between Denver Water and Boulder County. After a combined 5 hours and 45 minutes of public hearing, predominantly public testimony, the Boulder County Commissioners unanimously decided not the sign the Intergovernmental Agreement, not to put it to a vote, and not to hear comment from staff. Further, the Commissioners stated that they would wait until the release of the Final Environmental Impact Statement in order to see the actual impacts of the proposed project prior to making any decisions.1

The Final Environmental Impact Statement was release April 25, 2014, but lacks sufficient project details for Boulder County to make any determination of potential mitigations for project impacts.2

No agreement of any kind has been made between Boulder County and Denver Water and the preferred alternative – the expansion of Gross Reservoir by 72,000 Acre-Feet, contradicts Boulder County’s Comprehensive Plan.


1: Boulder County refuses to sign Gross Reservoir Agreement - http://www.dailycamera.com/boulder-county-news/ci_22329477/boulder-county-refuses-sign-gross-reservoir-agreement

2: Boulder County's FEIS Comment Letter, June 2014

#5 - The Fraser River is 70 to 80 percent depleted and this project would take the rest.

70 to 80 percent of the Fraser River and Upper Colorado River flows in the irrigation season months have already been diverted to the eastern slope. The additional diversions this project would create will divert a large percentage of the remaining flows causing additional tributary streams to run completely dry below diversion structures.

The upper Colorado communities have to adjust to imposed drought conditions every year because of trans-basin diversions to the eastern slope. Imposed drought conditions affect the recreation based economy, the water supply and wastewater treatment, and the ability to irrigate farms in western slope valleys. Yet, the proposed Moffat-Gross project would divert even more water out of the upper Colorado basins.

#6 - The diversions planned for in the Environmental Impact Statement only account for half the desired water.

Since at least twice the volume of stated project diversions are required to meet the project screening goal1, full impacts of the project should reflect twice the volume of additional "project" diversions and not be limited to impacts noted in the EIS between the modeled “Full Use” and “Proposed Project” Scenarios. Consequently, the impacts on the upper Colorado basins are expected to be much greater than the "negligible" impacts noted in the EIS.


1: Buchanan, 2014

#7 - The Environmental Impact Statement fails to account for significant impacts to hundreds of acres of wetlands on the Western Slope.

The Moffat-Gross Environmental Impact Statement fails to recognize the significant impacts of trans-mountain diversions on the already depleted Fraser/Colorado River Watershed, then argues contrary to US EPA and USGS that there is no significant stream recharge to valley floor groundwater, and concludes negligible to minor impacts upon riparian areas including wetlands.1

In fact, the cumulative impacts of trans-mountain diversions, including the proposed Moffat-Gross expansion, are more likely to mean 75-90% loss of watershed functions including hydrology, hydro-geochemistry, and habitat. We should expect significant impacts in the Fraser/Colorado River valley to traditional agriculture and riparian habitats including at least 312 acres of Jurisdictional Wetland.2


1: Wetland Impact Assessment for the Moffat‐Gross Expansion Project, Grand Environmental Services, 2014 - part 3

2: Wetland Impact Assessment for the Moffat‐Gross Expansion Project, Grand Environmental Services, 2014 - part 4

#8 - The Environmental Impact Statement fails to adequately address climate change impacts.

The recent National Climate Assessment (NCA) chapter on water resources1 projects significant impacts on water resources and management due to future climate change in the southwest United States. According to this report, due to changes in streamflow, current management practices will become less effective. The Southwest is a region projected to have large impacts on recharge rates, thus reducing water availability for reservoirs. The runoff reductions for the Colorado River in particular are expected to be on the order of 10-30% by the year 20502, and future climate change will lead to reductions in groundwater supplies3.

The Final Environmental Impact Statement states on page 12 of the Executive Summary that there is currently “no accepted scientific method for taking the general concepts associated with climate change and transforming them into incremental changes in stream flow or reservoir levels;” however, there have been numerous studies that use stream flow or land surface models to project stream flow, reservoir levels, and water deliveries4 in the future. Therefore, the impact of climate change can be assessed now.


1: Georgakakos et al., 2014

2: Barnett and Pierce, 2009

3: Crosbie et al., 2013; Taylor et al., 2013

4: Barnett and Pierce, 2009; McCabe and Wolock, 2007; Vano et al., 2012 among many others

#9 - Denver Water is misrepresenting the costs associated with the project.

The cost of expanding Gross Reservoir in the Final Environmental Impact Statement ($139.9 million)1 is inconsistent with and less than half that quoted in the FERC application ($364 million)2 for the same project. Many viable alternatives were screened out of the EIS process based on cost alone; likely including the Least Environmentally Damaging Practicable Alternative required under the Clean Water Act Section 404. If the cost of the perferred alternative - enlarging Gross Reservoir by 72,000 Acre-Feet - were properly calculated in the Environmental Impact Statement, it would likely be eliminated as a viable option.


1: Moffat Collection System Project - Final Environmental Impact Statement, Chapter 2, page 2-119, published April 2014.

2: Moffat Collection System Project - Draft FERC Hydropower License Amendment ApplicationTable D-1, page 38, published 2009

#10 - Several practicable alternatives to the Moffat Project exist that would have less damaging environmental impacts.

The project is classified as a “non water dependent” project because “The Basic Purpose of this project is water supply, and since water supply structures and their operations do not of necessity need to involve placement of dredged or fill material into waters of the U.S. the project is not water dependent.”1

Non water dependent projects have a special requirement and burden: “When a project is not water dependent, a presumption arises that there are practicable alternatives that do not involve special aquatic sites and have less adverse impact on the aquatic ecosystem.”2

The Corps presumes that practicable alternatives exist where a non-water dependent project will cause a discharge in a special aquatic site3. To rebut this presumption, a project proponent must provide “detailed, clear, and convincing information” that is verified by the Corps proving that an alternative with less adverse impacts is impracticable.

The Corps has the burden of determining the least damaging practicable alternative for a project and this burden “is heaviest for non-water dependent projects planned for a ‘special aquatic site’ such as a wetlands area”4.

Because the preferred alternative does affect special aquatic sites (SAS) in Gross Reservoir and on the Western Slope, pursuant to these regulations, Denver Water and the Corps must prove that there is no other alternative with less impact on the SAS. The Final Environmental Impact Statement fails to do this.


1: (DEIS, Appendix K Section 404(b)(1) Guidelines Compliance, p. K-26)

2: Hillsdale Envtl. Loss Prevention, Inc. v U.S. Army Corps of Eng’rs, 702 F.3d 1156, 1165 (10th Cir. 2012).

3: 40 CFR § 230 (a) (3) 2005

4: Greater Yellowstone Coal v. Flowers, 359 F.3d 1257, 1269 (10th Cir. 2004)