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ARLEIGH B. WEST picked up sediment below each dam and dumped it at the headwaters of the next downstream reser- voir. This created deltas and marshes, as in the Needles vicinity, which required emergency measures in 1944 and permanent correction beginning in 1949, when we placed our first dredge "The Color- ado" in operation. ~ The Topock Marsh opposite Needles has been a subject of some debate in our river manage- ment program. So, just a word to clear that up. Our records, maps, and aerial photographs show that the Marsh was created by the river's process of aggradation above Lake Havasu, when clear water be- low Hoover scoured out the channel. This aggradation or buildup of the riverbed tood place as the cur- rent slackened on reaching the upper end of Lake Havasu where the narrowing channel begins at Top- ock Gorge. The dead mesquite trees in the swamp, which you will see on the screen in a few minutes, grew there nearly a century ago, long before the dams were built. These trees are phreatophytes, not l;1.ydrophytes, and they thrived on dry land before they were killed by rising water from the river which spread out over a five-mile-wide area at Needles following the closure of Parker Dam. The Marsh, as we know it today, did not exist before the closure of the storage dams. I am pleased to report that Secretary of the Interior Stewart L. Udall has approved our modi- fied plan for corrective work in the Topock Gorge, and we have moved our Needles-based mainten- ance dredge into this area. This plan includes fish and wildlife features recommended by the Bureau of Sport Fisheries and Wildlife, which manages the Topock Gorge as part of the Havasu Lake Nation- al Wildlife Refuge. Our corrective program in the Topock Gorge, as well as for other reaches of the river, includes protection and enhancement of fish and wildlife values that developed both before and after our dams went into operation. From Davis Dam to the Mexican boundary, our multipurpose program of sal- vaging water, controlling sediment, and creating and preserving recreation, fish, and wildlife values is adding to the beauty and usefulness of the lower river. The Bureau of Reclamation will spend an estimated $6.7 million on facilities to enhance re- creation, fish, and wildlife values as part of its total lower Colorado River management program. I use the term enhance because absent the work of Reclamation on the river, there was no dependable recreation, fish, and wildlife base. Like the uncontrolled stream, these values fluctuated from years of plenty to years of drought. . Along the stretches of river where we have worked, parks, marinas, hotels, motels, residences trailer parks and other tourist facilities have sprung up. Without the security afforded by our river management activities, most of these developments would have not been practical. The water we save is yours. It will be retained in Lake Mead and released as necessary for your benefit, but will also aid all uses on the river. The 254,000 acre-feet of water we willsalvage annually by river management alone will irrigate 42,500 acres, at 6 acre-feet per acre, and will provide addi- tional benefits to recreation, fish, and wildlife. If used for M&l purposes, its value would be $18 mil- lion annually, computed at approximately $75 per acre-foot. Considering that our total river management program will cost about $50 million, that is a good investment. The work will soon repay its costs just in dollar value of the salvaged water, not in- cluding the other returns. As custodian of the river, it is not possible for Reclamation to completely satisfy all of the competitive demands. We must operate and manage the river to deliver water in conformance with contracts between the Secretary of the Interior and irrigation districts and municipalities, and within the scope of the United States Supreme Court Decree. And now, I will turn to my color slides as I continue to tell you about an errant river - - - the Colorado - - - and what we are doing with it. -5-