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As a result of the two diversions, during the primary irrigation season (April-October) , the river is essentially dry between the diversions and the La Verkin Springs which are located 2 miles below the lower-most diversion structure. The flow from the springs 3 averages about 11.9 ft Is. About 1 mile below La Verkin Springs is the discharge point of the C P National Corporation Powerplant No.4. This powerplant returns an average flow of between 10 and 20 ft3/s. About 14 miles below La Verkin Springs is the St. George- Washington Diversion Dam which is operated year round except for periods during canal maintenance. The existing water rights total about 86 ft3/s, although higher diversions are sometimes required for flushing sediments out of the canal system. This changes natural flows of the river drastically. Generally, riverflows below 86 ft3/s are all diverted into the canal system. As a result, riverflows below the diversion are near zero from June to September, except when flooding occurs. Average annual flows below the diversion are about 115 ft3/s. The major inflows in the reach below the St. George-Washington Diversion Dam are the Santa Clara River and various ditches return- ing irrigation water and sewage effluent from St. George (See Figure 1). These ditches add significant flow during the low-irrigation months (November through March) when most of the Washington Canal water is returned to the river. A few miles below St. George is a reach of the river where water seeps into the riverbed (influent reach). This reach extends about 6 miles from Bloomington, Utah, into the Virgin River Gorge. This influent reach causes the river to lose up to 100 ft3/s of water. The loss has been observed during high-flow winter months as well as low-flow summer months. As a result of this depletion, many years of records indicate little or no flow entering the Virgin River Gorge during the summer months. This gorge, about 14 miles long, extends 002514 6