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002251 Juan River basins. The goal is to recover species while allowing water development to take place. Glen Canyon Dam also has an adaptive manage- ment program that integrates scientific informa- tion with dam operations. Operations at Glen Canyon Dam have been modified through the 1996 Record of Decision for the Glen Canyon Dam Environmental Impact Statement. Power plant ramp rates and daily fluctuations are now in place to protect downstream resources in the Grand Canyon. Experimental test releases have included beach habitat building flows that occurred in the spring of 1996, and a low, steady flow in the summer of 2000. A temperature control device at the dam may be implemented in the future for the benefit of humpback chub populations. Upper Basin uses are expected to increase over the next 60 years and this will impact Lake Powell, leading to a greater number of 8.23 million acre-feet release years as opposed to the recent years where reservoir equalization/ spill avoidance has been practiced. JAYNE HARKINS UoSo BUREAU OF RECLAMATION, LOWER COLORADO REGION: Ms. Harkins provided an overview of the Lower Colorado River Basin. The average annual flow of the river is a little over 15 million acre-feet and there is a total storage capacity on the entire river of about 60 million acre-feet - so there is about four times the storage capacity of the river's inflow. Cur- rent storage is about 47.2 million acre-feet - 'about 80 percent of the basin's capacity. There are tributaries to the Colorado River below Glen Canyon Dam though the main annual tributary inflow to the Lower Colorado River is less than one-and-a-half million acre- feet. Tributaries include the Gila River and the Bill Williams River, however, the primary source of water for the Lower Basin comes from Lake Powell. Operation of Hoover Dam and Lake Mead is consistent with the 1970 Coordinated Long- Range Operating Criteria. Priorities from the Boulder Canyon Project Act are to provide flood control; improve navigation; regulate flows and provide water for consumptive use; and lastly, power generation. For Mead, there are essen- tially two types of operation: normal operation and flood control. Normal operations are carried out to meet downstream demands that include U.s. and Mexico consumptive use schedules; downstream evaporation and transpiration losses; and reservoir regulation in lakes Mohave and Havasu. Flood control regulations are authorized by the Corps of Engineers (Corps) and imple- mented through the Bureau. January through July, flood control releases are based on forecasts from the National Weather Service on the amount of inflow predicted to the system and the current available system space. From August 1"1 through January 1"1, specific minimum space requirements - such as one-and-a-half million acre-feet in Lake Mead - are implemented. The net result of flood control operations is that there are releases in excess of downstream require- ments. Inflows to Lake Mead have varied due to low water years and the filling of Lake Powell in the early 80s. Flows below Hoover Dam also have varied depending on flood requirements and water use. There are several facilities below Hoover Dam. Davis Dam, about 70 miles below Hoover Dam, is owned and operated by the Bureau as a way to re-regulate deliveries to Mexico. Lake elevations are kept within monthly targets throughout the year though such targets can be adjusted to meet short-term needs. Parker Dam is about 150 miles downstream of Hoover Dam. It, too, is owned and operated by the Bureau and was built as a forebay for the pumping plants that carry water to California and Arizona. In normal operations, releases from COLORADO RIVER DELTA BI-NATIONAL SYMPOSIUM PROCEEDINGS ENGLISH 33