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<br />. <br /> <br />. <br /> <br />. <br /> <br />002217 <br /> <br />operational in 1989 but has had to make major reductions in <br />system maintenance which could have long term impacts on the <br />System's capability in the future. <br /> <br />With the lack of specific funding in the President's <br />proposed budget for 1990, the NWS will be forced to consider <br />terminating the operation of the System in 1990. With the <br />Colorado River reservoir system likely to remain in a full or <br />near full condition through the mid-1990s and possibly <br />beyond, periodic flood control releases may be required <br />during this time, and any reduced flood forecasting <br />capabilities would pose increased risks to those along the <br />Colorado River. A near-full condition implies that the <br />reservoir system has a high probability of refilling, even if <br />drawdown during a couple of below average runoff years. This <br />is due to the fact that river water use by the Basin states <br />and Mexico is less than the river's long-term average annual <br />supply and is likely to remain less than the average annual <br />supply through, at least, the mid-l990s. <br /> <br />RECOMMENDATION <br /> <br />It is strongly recommended that the Congress provide <br />sufficient annual federal funding in 1990 and thereafter for <br />the full operation and maintenance of the National Weather <br />Service's Colorado River Flood Warning System. <br /> <br />IV. ISSUE <br /> <br />The existence of hazardous river navigation conditions <br />and damage to public and private property, river bank <br />stabilization, and erosion control works caused by power <br />boats when river flows are over 28,000 cubic feet per second <br />(cfs) . <br /> <br />DISCUSSION <br /> <br />Since the closure of Hoover Dam in 1935 and until 1983, <br />monthly average river flows in the lower Colorado River have <br />exceeded 28,000 cfs on only one occasion. Flood control <br />releases from Davis Dam in excess of 28,000 cfs are about <br />5,000 cfs greater than daily peak releases for power <br />generation and nearly twice the maximum monthly average <br />release for downstream water needs. Flows over 28,000 cfs <br />will sometimes cover channel training structures and create <br />navigational hazards. In addition, waves generated by power <br />boats operating on the river during these flow levels can and <br />do cause severe river bank and structure damage. <br /> <br />1II-9 <br />