skip to the content of this page Arizona's Official Website Arizona Department of Water Resources
Arizona Department of Water Resources Arizona's Official Web Site
Securing Arizona's Water Future
Surface Water Conditions in the Yuma Basin

Streamflow data, including average seasonal flow, average annual flow and other information are shown in Table 7.11-2.  Reservoir and stockpond data, including maximum storage or maximum surface area, are shown in Table 7.11-3. The location of streamflow gages identified by USGS number and large reservoirs are shown on Figure 7.11-5.  There are no flood ALERT stations or USGS runoff contour data available for this basin.  Descriptions of stream, reservoir and stockpond data sources and methods are found in Volume 1, Appendix A. 

Streamflow Data

  • Refer to Table 7.11-2.
  • Data from seven stations located on two watercourses are shown in the table and on Figure 7.11-5.  Four stations have been discontinued and two are real-time stations.
  • Highest average seasonal flow varies from station to station.  Flows are impacted by regulatory releases, diversions and return flow.
  • The largest annual flow recorded in the basin is almost 26 million acre-feet in 1909 at the Colorado River at Yuma Station.  Mean annual flow at this station is 10.1 million acre-feet.  The hydrograph of annual flows at this station shows the dramatic drop in river flow during the construction of Hoover Dam from 1931-1935.  (See Figure 7.11-4)

Reservoirs and Stockponds

  • Refer to Table 7.11-3.
  • The basin contains two large reservoirs.  The largest, Mittry Lake has a maximum storage of 4,850 acre-feet. This reservoir is used as a fish and wildlife pond and for flood control.
  • The other large reservoir, Morelos Diversion Dam was constructed by Mexico pursuant to the 1944 Treaty to provide Mexico a mechanism for the utilization of Colorado River water.
  • Surface water is stored or could be stored in two small reservoirs in the basin. 
  • There are no registered stockponds in this basin.

Click here for Table 7.11-2

Table 7.11-2 Streamflow Data for the Yuma Basin

Click here for Table 7.11-3

Table 7.11-3 Reservoirs and Stockponds in the Yuma Basin

Click here for Figure 7.11-5

Figure 7.11-5 Yuma Basin Surface Water Conditions


Arizona Water Atlas Home

Lower Colorado River Planning Area Home

References and Supplemental Reading for the Yuma Basin

Colorado River
Lower Colorado River Planning Area
Click to download Volume 7
Mainstreet Yuma
Agriculture in Yuma Basin