Gross Reservoir, located in

Boulder County, Colorado Boulder County is a county located in the U.S. state of Colorado of the United States. As of the 2020 census, the population was 330,758. The most populous municipality in the county and the county seat is Boulder. Boulder County comprises th ...

, is owned and operated by

Denver Water Denver Water serves 1.4 million people in the City and County of Denver, Colorado, and a portion of its surrounding suburbs. Established in 1918, the utility is a public agency funded by water rates and new tap fees, not taxes. It is Colorado's ...

. Completed in 1954, the reservoir has a surface area of 440 acres, and the spillway sits at 7,225 feet elevation. The reservoir receives water from the western side of the Continental Divide through the

Moffat Tunnel The Moffat Tunnel is a railroad and water tunnel that cuts through the Continental Divide in north-central Colorado. Named after Colorado railroad pioneer David Moffat, the tunnel's first official railroad traffic passed through in February 192 ...

. South Boulder Creek flows out of the 340 foot-high dam.

Recreation

The reservoir provides opportunities for fishing (including ice fishing), hiking, canoeing, kayaking, and some camping. No water-contact sports such as swimming or wading are allowed. Only non-motorized boats are permitted — the type that can be attached to the top of a car.

Expansion project

The proposed expansion of Gross Reservoir would allow Denver Water to store 77,000 additional acre feet of water, drawn mostly from the

Fraser Fraser may refer to: Places Antarctica * Fraser Point, South Orkney Islands Australia * Fraser, Australian Capital Territory, a suburb in the Canberra district of Belconnen * Division of Fraser (Australian Capital Territory), a former federal ele ...

and Williams Fork Rivers. Construction on the project, expected to be complete around 2025, will raise the level of the dam by , resulting in an additional of water storage capacity in the reservoir and making it the tallest dam in Colorado.

applied to the

U.S. Army Corps of Engineers , colors = , anniversaries = 16 June (Organization Day) , battles = , battles_label = Wars , website = , commander1 = ...

for a permit under section 404 of the

Clean Water Act The Clean Water Act (CWA) is the primary federal law in the United States governing water pollution. Its objective is to restore and maintain the chemical, physical, and biological integrity of the nation's waters; recognizing the responsibiliti ...

, required to construct the expansion, and that permit was granted in 2017. In response, several environmental groups sued USACE on grounds that the agency's deliberations about granting the permit violated the Clean Water Act, Endangered Species Act of 1973, Endangered Species Act, and National Environmental Policy Act. In July 2020 the Federal Energy Regulatory Commission granted a required modification to the Federal Power Act license granted to Colorado Water for Gross Dam before it was built. A contract for design services was awarded to Stantec, an engineering consulting firm, in 2017. Boulder County, Colorado, Boulder County announced in spring 2019 that it would require Denver Water to obtain a land use permit under Colorado law before commencing the expansion project. Denver Water submitted its application for that permit in September 2020.

Climate

According to the Köppen Climate Classification system, Gross Reservoir has an oceanic climate, abbreviated "Cfb" on climate maps. The hottest temperature recorded at Gross Reservoir was on July 9, 2003, June 23, 2012, June 26, 2012, and June 22, 2016, while the coldest temperature recorded was on February 2, 2011.

References

External links

Expansion Project official websiteAnti-Expansion Project official website
{{DEFAULTSORT:Gross Reservoir Reservoirs in Colorado Protected areas of Boulder County, Colorado Bodies of water of Boulder County, Colorado 1954 establishments in Colorado

Recreation

Expansion project

Climate

See also

References

External links