Current uses/operation
Reservoir Background
Reservoir Storage/Flood Control
Water Deliveries
Water Transfers
Fisheries Flows
Recent operating challenges
Concerns for future operations
Return to Prosser Creek home page
Return to first page
Reservoir Background
Prosser Creek Dam was completed by the U.S. Bureau of Reclamation in
1962 as part of the Washoe Project. The primary functions of the reservoir
are flood control in the Reno/Sparks area and water exchange as determined
by the Agreement for Water Exchange Operations of Lake Tahoe and Prosser
Creek Reservoir. This agreement provides for the release of water from
Prosser Creek Reservoir to meet Floriston rates in lieu of making the releases
from Lake Tahoe, thus enabling Lake Tahoe to provide minimum fishery flow
in the Truckee River fishery just below the lake.
Reservoir Storage/Flood Control
During the flood season, November 1 through April 10, the storage has
to be maintained below 9,800 acre-ft. This is variable in the spring depending
on the given snow pack (i.e. a small snowpack allows operators to start
filling the reservoir earlier). Note that Prosser Creek Reservoir
is used extensively for flood control, with 20,000 acre-ft of its 29,800
acre-ft storage capacity allotted for flood control during the flood season.
Once the threat of flooding is reduced, excess water above the flood capacity
is stored in the reservoir.
Water Deliveries
The water is released throughout the summer for downstream demands.
Enough water is released to meet flood protection needs in the fall. Water
is delivered to downstream users by timed releases from Prosser Creek Reservoir.
On average, It takes approximately 27 hours for water to reach Reno, and
39 hours for water to reach the Derby Diversion.
Water Transfers
Like Boca, an important use of the storage is water transfer between
Lake Tahoe, Donner Lake, and other reservoirs.
Fisheries Flows
A minimum flow of 5 cfs is required to maintain fisheries in the Little
Truckee River.
Recent operating challenges
Operators are currently challenged with a high snow runoff factor due
to late snowfall. This mandates that more storage remain in the reservoir
beyond the flood season, which could pose challenges in meeting the demands
of downstream users during the irrigation season.
Concerns
for future operations
As with other water supplies in the state, the Truckee River is under
increased demand due to residential development. Much of this development
is replacing agricultural lands. The municipal water demands are not as
flexible as agricultural demands and put pressure on environmental and
other uses. Operations of Prosser Dam will have to be modified to accommodate
these increased demands without degrading other uses.
Return to top of page