Truckee River
 
The Truckee River starts at the outlet from Lake Tahoe at Tahoe City goes north to Truckee, then north-east to Reno and ends in Pyramid Lake north-east of Reno.
Several streams feed into the River between Truckee and Reno. It is 108 miles long.

Total precipitation at Tahoe City for the water year (October 1 - September 30) is projected to be 26 in for 2012.
Mean annual precipitation is 31 in. The middle quartile values are from 21 - 43 in.

Table 3-1. Selected Upper Truckee River Basin Truckee River Inflows Above the Farad Gaging Station
(Average Annual Runoff Volumes in Acre-Feet [Flow Rates in Cubic Feet per Second])
Gaging Station Location Average-Water Year
(af [cfs])
Low-Water Year
(af [cfs])
High-Water Year
(af [cfs])
Lake Tahoe Outlet (at Tahoe City) 161,450 [223 cfs] 110 [0.15 cfs] 832,570 [1,150 cfs]
Donner Creek (at SR 89) 60,890 [84.1 cfs] 18,750 [25.9 cfs] 102,800 [142 cfs]
Martis Creek (below Martis Dam) 19,470 [26.9 cfs] 5,000 [6.90 cfs] 53,940 [74.5 cfs]
Prosser Creek (below Prosser Dam) 65,950 [91.1 cfs] 17,660 [24.4 cfs] 154,930 [214 cfs]
Little Truckee River (below Boca Dam) 123,800 [171 cfs] 40,250 [55.6 cfs] 340,270 [470 cfs]
Bronco Creek (at Floriston, California) 9,920 [13.7 cfs] 4,400 [6.06 cfs] 15,420 [21.3 cfs]
af = acre-feet cfs = cubic feet per second USGS = U.S. Geological Survey
Source: Farad Diversion Dam Replacement Project - Chapter 3 - Hydrology, 2002

Mean annual precipitation in the Tahoe basin is 31 in. The middle quartile values are from 21 - 43 in/year.
Assuming runoff is proportional to precipitation this means that about 25% of the time all the water entering the lake would be lost to evaporation, so output to the Truckee River is restricted and the lake level will be lower at the end of the year.
Outflow to the Truckee River is adjusted to keep the water level within these limits. However, there are minimum flows to supply water for Reno and maximums to avoid flooding in Reno.
See the Floristion Rule

According to the Truckee River Chronology at nv.gov, Oct, 2011, Truckee river outflow can range from 110 acre-ft [0.15 cubic ft per sec (cfs)] to 832,570 acre ft [1,150 cfs].
The minimum according to another source is 70 cfs.

Mean monthly flows (cfs) in the Truckee River at Donner Creek based on model results in wet, median, dry, and extremely dry hydrologic conditions. Shaded boxes indicate when recommended minimum flows of 75 cfs are not met.
Source: Truckee River Riparian Vegetation and Fluvial Geomorphology Study, 1993
Wet Median
Apr May Jun Jul Aug Sep Oct Apr May Jun Jul Aug Sep Oct
CC 1577 1552 1256 547 442 455 340 623 778 518 173 110 223 260
NA 1504 1516 1252 543 441 458 347 602 762 517 174 112 226 270
LVNA 1504 1516 1252 543 442 458 348 603 763 516 174 112 228 271
TROA 1534 1546 1293 544 329 307 309 621 805 551 215 118 137 202
Dry Extremely Dry
Apr May Jun Jul Aug Sep Oct Apr May Jun Jul Aua Sep Oct
CC 275 289 158 90 68 89 23 227 253 133 63 26 44 5
NA 273 282 158 89 67 73 29 229 253 130 60 24 34 12
LWSA 273 282 158 89 66 72 31 229 253 130 81 24 32 14
TROA 272 391 247 105 68 61 41 201 260 142 64 22 35 21

 CC - Current Condition
 NA - No Action
TROA - Truckee River Operating Agreement
LWSA - Local Water Supply Alternative


Source: Truckee River Operating Agreement usbr.gov, 2008

Table 1. Statistics for major reservoirs in the Truckee River Basin.
Reservoir Name Storage
(Acre-Feet)
Drainage
Area

(mi2)
Date
dammed
Elevation Function(s)
Lake Tahoe 744,6001 506 19132 6227 Storage for instream flow and irrigation
Donner Lake 9,500 14 1930s3 5900 Municipal and irrigation water supply
Martis Creek 20,300 40 1971 5760 Flood control
Prosser Creek 29,800 50 1962 5680 Flood control, instream flow, water conservation in Lake Tahoe
Independence Lake 17,500 8 19394 6300 Municipai supply
Stampede
Reservoir
226,500 136 1970 5760 Pyramid Lake fish flows and flood control
Boca Reservoir 41,100 172 1937 5600 Municipal and irrigation water supply
1. Only the top 6 ft of Lake Tahoe that is controlled by the dam is counted.
2. The first dam was constructed in 1871 or 1874
3. Original dam was constructed in 1877
4. Small dam originally constructed in 1879
Source: Truckee River Riparian Vegetation and Fluvial Geomorphology Study, 1993

Links:
Truckee River Operating Agreement TROA.net
Truckee River Operating Agreement usbr.gov, U.S. Bureau of Reclamation, 2008
Truckee River Operating Agreement (Biological Resources), U.S. Bureau of Reclamation, January, 2008
  Includes "Truckee River Riparian Vegetation and Fluvial Geomorphology Study", U.S. Fish and Wildlife Service, Sept., 1993
  Executive Summary

Truckee River Chronology at nv.gov, Oct, 2011
California Creeks - Truckee Floriston
www.truckeeriverwc.org/about/watershed


last updated 25 June 2012
West Shore Info | Ski Info | Directions | Homewood Map.