Senator Wash Dam


Senator Wash Dam and Reservoir, an offstream pumping facility, is located about 18 miles northeast of Yuma, Arizona, on the California side of the Colorado River 2 miles upstream from Imperial Dam and at the river-end of Senator Wash. The purpose of this strategic off stream retention reservoir is to improve water scheduling of the Colorado River. This is accomplished by storing part of the riverflow upstream of Imperial Dam when it is not needed and releasing it to the river for downstream use when needed. 

RegionFacilities in Lower Colorado | Lower Colorado Home Page
ProjectColorado River Front Work & Levee System
Dam TypeRolled earth embankment
ReservoirSenator Wash
Location 18 miles northeast of Yuma, Arizona
Original Construction1964-1966
Modified Construction 2004
National ID NumberCA10185
Hydrologic Unit Code

Structural Height93.6 ft
Hydraulic Height (Normal Operating Depth at Dam)84.0 ft
Top Parapet (Elevation)
Spillway Crest Elevation
Crest Elevation265 ft
Crest Length2,342 ft
Crest Width30 ft
Base Width619 ft
Volume of Dam Construction Materials1,248,000 cu-yds
Streambed at Dam Axis
Top of Exclusive Flood Control Pool (Elevation)
Top of Joint Use Pool (Elevation)
Top of Active Conservation Pool (Elevation)251 ft
Top of Inactive Conservation Pool (Elevation)
Top of Dead Storage Pool (Elevation)

Hydraulics & Hydrology
Total Water Storage at Elevation 13,863 af
Maximum Water Surface Elevation251 ft
Normal Water Surface Elevation 240 ft
Spillway Type Uncontrolled concrete overflow with flip buckets
Spillway Capacity at Elevation1780 cfs at 251 ft
Auxiliary Spillway
Auxiliary Spillway Capacity at Elevation
Uncontrolled Spillway Capacity at Elevation
Outlet Works Capacity at Elevation
Diversion Capacity at Elevation
Drainage Area21.0 sq mi
Hydrometeorological Report (HMR)
Probable Maximum Flood (PMF) Report

Contact Information
TitleArea Office Manager
OrganizationYuma Area Office
Address7301 Calle Agua Salada
CityYuma, AZ 85364
Phone (Office)928 343-8100
OrganizationImperial Irrigation District
AddressPO Box 937
CityImperial, CA 92251
Phone (Office)760 482-9600

Last updated: Jun 29, 2009