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taken June 1984 at Nebraska City, just upstream of the bridge and you can see there is not only flooding along the Missouri from the river itself in the unlevied areas, but there is also the drainage water trapped behind the levees. We still do have a !lood problem. This is the same location during the winter with the river frozen over. We've had some ice jams this year above Sioux City and they have cut off the water sup- ply at times to the downstream reaches, but we haven't had any problems yet this year with ice jam flooding. Looking at the impacts of flood control-the flood control function, as Duane mentioned, takes first priority. It is also the function that conflicts with all of the ot.her seven functions because it requires an empty storage space in the reservoir. The other func- tions require stored water to maintain t.hese functions through periods of inadequate flows into the reser- voirs. Flood control's impact on hydropower generation drastically reduces the generation during flood control operations. Reduced releases to prevent flooding below a specific reservoir has a domino effect and may re. quire release reductions at more than one of the six main stem reservoirs. At quite a few of our public meetings it's been mentioned that we should reallocate some of the carryover storage to additional flood con- tro and we are just starting to look at a study on that. Taking about 5 million acre-feet of the flood control carryover storage for flood control has produced a pre- liminary estimate that, normally we would have an average annual hydropower generation of 9.4 million kilowatts, and we would cut that down to 9.1 million kilowatt hours. We also looked at the effect on navi- gation of doing this. Currently, with 85 years of rec- ords. we can maintain an eight month navigation season with four minimum flows in 73 of the 85 years, or 86% of the time. The preliminary results of these studies indicate taking flood control storage would probahly have a more significant effect on the navi- gation function than it showed on the power function. Going to endangered species, more flood control storage could infringe because lower spring releases may require higher late summer and fall releases to evacuate the stored water. Fish and wildlife-it would have a positive impact in the reservoirs since greater pool fluctuations increase the chances of the pool rise when the fish are spawning, but lower spring releases may negatively impact the fish spawn downstream of the reservoir. It would have a good effect in the res- ervoirs and a bad effect downstream. Recreation-it would lower the carryover storage 34 level and would result in greater pool level fluctuations in the reservoirs which could be detrimental. Irrigation-here again, addition flood control would not really impact on OUT present irrigation use. Water supply and water "quality-this system was designed to have an annual carryover storage to handle water supply and water quality for the repeat of the record drought of the 19aOs. Reallocation and car- ryover storage to flood control could seriously impact this capability, but system criteria would have to be adjusted to provide the water quality and storage be- cause it has priority over the power and navigation releases. So we would still have to adhere to the water supply and water quality. HYDROELECTRIC POWER Going to the impacts of hydropower generation on the other functions, I've shown a grid of the hydro- power system in this area showing that we do supply quite a few of the states and also areas outside of the basin. Hydropower is an important aspect and impact on !load control. Again, I mention flood control takes first priority, so really there would be no impact On flood control since release reductions are made during the flood control periods. Endangered species-power is in conflict or com- petition since generation and peaking capability dur- ing the mid-May to mid-August period could be lowered. Fish and wildlife--the impact from hydropower could adversely effect the environment, but we have eliminated this primarily through coordination with the fish and wildlife interests and it's accommodated to the maximum extent possible through limited peak- ing for the downstream spawn period and unbalancing the reservoirs upstream for revegetation to enhance fish spawning. Recreation is sometimes negatively impacted in the river reaches below the reservoirs, but special regu- lations are coordinated with local interest to enhance recreation such as maintaining minimum releases dur- ing low power demand periods on weekends to the fishermen. Here again, there is some impact to irri- gators downstream at intake structures, but not a ma- jor impact at our l..-el of depletions. Navigation-there would be no significant impact because service to power normally takes a back seat