This is probably all but certain to happen, I think. Here is a reprint from my post in May about it:
http://www.mountainbuzz.com/forums/f11/2008-south-platte-protection-plan-annual-meeting-18551.html
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Part of the deal when Two Forks Dam was stopped was that the parties had to develop other sources to get the water that would not be produced from TFD, and would do so within 20 years. Alternatives to the Two Forks Dam continue to be considered, including the expansion of Gross Reservoir. This would result in the inundation of at least some of USB. See the notes below for more on this, as it may become a huge issue for the whitewater community. The proposed expansion would result in the last 120 vertical feet of USB being inundated. Since I hiked out after an early chundering, I don't personally know if the last 120 vertical feet (about 1/2 mile of the current creek) have good rapids.
SOUTH PLATTE PLANNING TASKFORCE MEETING
Purpose: To plan alternative sources to develop yield that would otherwise have come from the Two Forks Dam water right – if alternate yields are developed during the 20-year moratorium on the Dam, then the Two Forks right would likely be abandoned. Focus is on conservation, recycling and new sources. The new source projects presently under consideration include:
1. Gross Reservoir Expansion (presented by Travis from DW)
a. Expansion of 72K acre-feet – this presently is the preferred option
i. Projected start would be in 2013, 18K acre-feet yield (15K to Denver, 3K to Arvada)
ii. In 2016, demand will exceed supply of water and because demand is still rising, by 2030, shortfall is expected to be 34K acre-feet, with the remaining 16K to be recovered through conservation
iii. Cost estimated at $8,000 per acre-foot
iv. At this time, this is the preferred option under consideration, but no application has been submitted to the Corps of Engineers
v. This expansion would extend the Reservoir upstream from present headwaters boundary, inundating portion of lower USB
vi. Current spillway is at elevation of 7282 feet, new one would be at 7400 feet, extending the Reservoir about ½ mile up into USB; you can see where this is by finding the where this contour line intersects with the creek on a topo map
vii. Draft EIS is expected probably in September – that is when further information will be available and comment period will open
b. Gross & Liden Reservoirs combined enlargement
c. 52K enlargement of Gross Reservoir plus 5K acre-feet of storage in gravel pits
d. 52K enlargement of Gross Reservoir plus 5K acre-feet of storage in aquifers under Denver
e. 60K enlargement of Gross Reservoir plus additional storage of purchased agricultural wate
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Look at section vi for the skinny on RIMBY - find that spot and you will know where the new level will be. I have no idea where RIMBY is on the map, so I can't say if it would go under. The main point about this whole thing is that if DWB doesn't get the water from new sources (including recycling and conservation) that it would have gotten from the Two Forks Dam, then the Dam is *back*on*the*table* Those who were boating or climbing in the valley back then will recall that this was the deal that was brokered to stop the dam. Now comes the lesser of two evils.