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MANAGING AN ERRANT RIVER - THE COLORADO By ARLEIGH B. WEST. Regional Director Bureau of Reclamation, Region 3 I was pleased when your Program Chairman Dal Cole invited me to talk to you about Recla- mation's Colorado River management program. I know you are in sympathy with our salvage effort, for it is your water we are saving. It is in large part due to your support that our program has been suc- cessful, and is now accepted throughout the Lower Colorado River Basin as a wise multi-purpose water and land conservation practice. With the aid of color slides and the map on the stage, I will bring you up to date on our river work. But first, some background. Note that the river map shows the divisions of our management activities. . " The original studies estimated that the river management program would ultimately salvage 254,000 acre-feet of water annually. The channel improvements in the Mohave, Palo Verde, and Laguna Divisions already conserve annually 129,000 acre-feet of water previously unavailable for irri- gation and municipal uses. We are about at the halfway point in terms of total salvaged water. Our sediment studies show that we have accomplished about one-third of the 1,570,000 tons per year of total sediment reduction expected from the program. To understand and appreciate our program as it is now and as it will be, we must go back to the days when there were no dams on the lower Colorado. The Colorado River, B.H. (before Hoover), was a muddy, errant stream. Old timers have told me that one of the major benefits of Hoover Dam, not often recognized today, was the elimination of the silt deposits that accompanied each irrigation. Emerging plants in farmers' fields were covered with silt, the carefully established levels of fields were upset by continual aggradation, and headgates had to be raised periodically. Then, far more than now, the river carried great quantities of silt. It twisted through the val- leys like a great snake, piling up silt deltas here and there, eroding its banks and bed, changing its course numerous times. It was not a serene, desirable stream, even though time dulls the memory, and to some the good old days always seem better than they were. Nor was it an ideal fish and wildlife habitat. When it was not flooding, it was only a trickle. The clear regulated river and reservoirs are now enjoyed by over seven million recreationists annually. On the weekend of Nevember 25 and 26, 20,000 people gathered at Havasu City for the annual outboard races. Parker Dam and Lake Havasu make possible this great Havasu City complex. Hoover and other Reclamation dams, therefore, have made the Colorado what it is today. Without these dams, fishing, hunting, and other forms of recreation along the river would be minimaL Increasing depletions, upstream and downstream from Hoover Dam, make these controls by Reclam- ation works vital. ~ Not too long ago, as much as 10 million acre-feet of Colorado River water flowed past the Mexican boundary into the Gulf of California in a single year. The river channel below the boundary today is dry; except in periods of unpredictable storms below Parker Dam, no unused flow reaches the ocean. .. y Control and desilting of the Colorado River began in 1935 at Hoover Dam when its gates were closed and Lake Mead began forming. Other Reclamation dams downstream - - - Davis, Parker, and Imperial - - - came later, to further control, regulate and desilt the river. The clear water released from each of these dams, however, has created new problems which our river management program is cor- recting. The river, accustomed to carrying tremendous quantities of silt for centuries from the water- shed upstream, has been readjusting its gradient following the building of the dams. Its clear water -4-