Truckee River Sedimentation Study (1993)

Written By
Brad R. Hall, William A. Thomas
Hydraulics Laboratory, US Army Corps of Engineers
Waterways Experiment Station

Technical Report HL-93-13
September 1993

The U.S. Army Engineer Sacramento District (CESPK) is formulating a
local flood protection project along the Truckee River at Reno, Nevada. The
District is completing a Sediment Engineering Investigation (SEI) in conjunction
with the project design to assess existing and project condition sedimentation
processes of the Truckee River. This report is part of the SEI and
provides an assessment of the existing sedimentation conditions of the study
reach. A sediment budget and associated channel changes for both average
annual and design flood conditions are developed in this report.

The Truckee River study reach is located near Reno, Nevada and extends
from the Vista gage at approximately River Mile (RM) 43.9 to just upstream
of the Booth Street bridge at RM 53.0. A map of the study area is shown on
Figure 1. A number of inflow points occur along the study reach including
urban inflows, irrigation diversion wasteways, and tributary drainages. Two
major tributaries provide additional discharge; Steamboat Creek at RM 45.5
and the North Fork Truckee drain at RM 44.8. The Truckee River watershed
upstream of the study reach includes the Lake Tahoe watershed and portions of
the eastern slope of the Sierra Nevada mountains in California and Nevada.
The Truckee River watershed area at the upstream end of the study reach is
approximately 1,067 square miles. The majority of the Truckee River runoff
originates in the Sierra Nevada mountains and flows through the study reach.
Downstream of the study reach, the Truckee River flows east-northeast until it
empties into Pyramid Lake, 43 miles downstream of the Vista gage. Pyramid
Lake is a terminal lake for the river basin which has no outlet to the ocean.

The Truckee River is a perennial stream characterized by pool and riffle
channel morphology. Several bridge crossings and water diversion structures
are found in the study reach. Man made channel modifications, especially
within the upper 3 miles of the study reach, have limited the amount of channel
migration. Bed material size decreases through the reach, and the channel
bed is armored at base flow discharge. The flood plain and back water storage
areas have been encroached upon by areas of urban construction and earth fill
in recent years.