o S. B
Moffat Tunnel GILPIN
WINTER PARK
COUNTY
on Creek Ralst
Vasquez Tunnel
SUMMIT COUNTY er Riv ue Bl
SILVERTHORNE
Clear Creek
CLEAR CREEK COUNTY
BROOMFIELD COUNTY
South Boulder Diversion Canal
Ralston Reservoir
IDAHO SPRINGS
Gumlick Tunnel
u
JEFFERSON COUNTY
Finally, Northern agreed to forego future water development in Grand County except in cooperation with the West Slope. In exchange, Grand County no longer opposed the firming project. Although the 1041 permit has been granted, as of August 2014 the Windy Gap Firming Project was still awaiting federal permitting approval. Denver’s Moffat Firming and the Colorado River Cooperative Agreement The 2002 to 2003 drought also affected Denver Water. Denver’s planners projected a shortage of 34,000 acre-feet of water by 2030 to meet demand, some of which can be made up through aggressive conservation efforts. But Denver still expects to need another 18,000 acre-feet of firm yield each year. The utility’s plan? Enlarge Gross Reservoir on South Boulder Creek, the East Slope storage vessel for the Moffat Project, completed in 1955. Denver Water worked to enlarge the reservoir from 42,000 acre-feet to 114,000 acre-feet. This will enable Denver to draw more water in average and above-average water years from the West Slope and Boulder Creek. Denver announced these plans in 2003, at which point the UPCO study began to be absorbed into broader negotiations. By 2007, Denver Water and the Colorado River District were again deep in discussions over Denver’s Blue River Decree. Blue River issues, the looming Moffat expansion, and other discussions along the Colorado River led Denver Water and the Colorado River
1996 Wolford Mountain Reservoir is completed jointly by Denver Water and Colorado River District
Conduits 16 & 22 DENVER
Dillon Reservoir flushing flows every five years—flows that will scour the riverbed, removing built up sediment and other compacted materials, improving overall riparian health, and creating more aquatic insect habitat. A flow of 1,200 cubic feet per second will bypass Windy Gap Dam every five years, and 600 cubic feet per second every three years. Previous bypass flows had been 450 cubic feet per second every three years. Grand County also required that the Subdistrict discontinue pumping at Windy Gap when stream temperatures are too high. Now, pumping at Windy Gap will completely stop when flows reach “acute” temperatures that could lead to fish kills, and new pumping as part of the firming project will be discontinued when temperatures approach “chronic” or sustained levels. Grand County can also obtain up to 5,000 acre-feet of water when available to boost late-summer streamflows. Grand Lake, Colorado’s largest natural lake and the northernmost collection basin on the West Slope in the Colorado-Big Thompson Project system, has suffered from water clarity and quality issues. These issues vary seasonally with a change in lake color and clarity most evident July through September when Northern Water is pumping water into the lake. As part of the agreement, Northern and the Bureau of Reclamation are now working to collect data to determine the root causes of Grand Lake’s water quality issues and eventually take action to improve lake health.
Pla tte
Gross Reservoir
NEDERLAND
R i ver
BOULDER ek l d e r Cr e
FRASER
r ive kR For
Green Mountain Reservoir
WELD COUNTY
Bou l d
N. Bo u
r
GRAND COUNTY
s am illi W
Williams Fork Reservoir
Boulder Reservoir
So uth
GRANBY
BOULDER COUNTY
Indian Peaks Wilderness
e Riv er as Fr
Windy Gap Reservoir
KREMMLING
LONGMONT Cre ek
Granby Reservoir
LYONS CONTINENTAL DIVIDE
er
r Rive ado r o l Co
Grand Lake Shadow Mountain Reservoir
r Cre ek
Arapaho National Forest
Rocky Mountain National Park
lde
MOFFAT SYSTEM
ADAMS COUNTY
LEGEND Tunnel Pipeline Canal Pumpstation Powerplant
District to negotiate. The entities were set to meet and resolve Blue River issues once and for all, but while they were at it, why not resolve even more? As time went on, more parties joined the discussion and after about seven years, more than 40 parties negotiated a landmark water management agreement between Denver and 17 West Slope signatories: the Colorado River Cooperative Agreement. The agreement received its first signature in 2012 and the last in 2013. The CRCA is between Denver Water, the Colorado River District, Eagle County, Grand County, Summit County, and various towns, water districts, ski areas and others along the Colorado River from the headwaters to Grand Junction. The agreement is complex but featured major negotiating points. In the end, the agreement helped the West Slope in many ways. It compelled Denver Water to define and limit its service area, with a few exceptions, thereby limiting the amount of water it will continue to seek for expanding populations. Denver’s ever-expanding service area had been an unsettled Blue River Decree issue. “The Blue River Decree limits Denver to use its Blue River water in the Denver Metro area and only the Denver Metro area,” says Peter Fleming, general counsel for the Colorado River District. “The intent of that provision was to limit Denver’s diversions from the West Slope.” Now, if Denver serves outside the newly defined service area, the West Slope receives
1998 Eagle River MOU is signed between Colorado Springs, Aurora and West Slope entities regarding Eagle River development they will pursue in the future
CITIZEN’S GUIDE TO COLORADO’S TRANSBASIN DIVERSIONS
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