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L~l,I;;"i3 to navigation. Gavins Point is oper~ted to level out the Power fluctuations for the 732 mile navigation channel from Sioux City to St. Louis. Equal and com- mensurate emphasis is given the power function dur- ing the winter period as was given navigation in the summer. Water supply-here again, no significant impact. IRRIGATION We do have over 400 permits for irrigation with- drawals in the reservoir areas, but they are mostly small. The large federal irrigation projects that were originally envisioned in the Pick-Sloan Plan were never constructed or completed so our impacts for op- erating for irrigation are very minor. We see no pri- mary impacts on any of the functions from irrigation. NAVIGATION Going on to navigation, we do target flows for the four stations downstream from Cavins Point to main- tain navigation flows. I showed a loading operation at Ag Processors in Sioux City and the Sioux City/New Orleans terminal here in Omaha, Nebraska. I did at- tend a navigation conference in Council Bluffs last year that indicated there are some spinoff henefIts, even though uur tonnage is low, from the navigation function providing competitive rates for all types of transportation because barge tramc is available. An- other spinoff benefit is that the stabilized channel for navigation also protects the riverbanks and after a flood like we experienced in 1984, the river channel is back where it belongs after the flood, which is quite different on some rivers like the Platte River and the Elkhorn River which continue taking farmland. Looking at the impa.cts on navigation, there is some conflict with flood control, but this is minimized by reducing to minimum flow levels for navigation during downstream floods and advising the Coast Guard when to curtail traffic due to wave and wake action on downstream levees. In June of 1984 navigation was curtailed for a 30-day period because of the high water. Hydropower is in competition with navigation re- leases, but normally we are able to accommodate the hydropower requirement. If we didn't have navigation we would probably be better able to adjust to the hy- dropower demands. Irrigation during severe droughts-the benefit to the river reaches downstream of the reservoirs would result from the release of water for navigation. Recreation-there is a benefit during droughts be- cause we would be releasing water for downstream river reaches. That would go the same for fish and wildlife on spawning operations downstream. Water supply-operations for navigation is also compatible with water supply requirements down- stream of the reservoirs. RECREATION Recreation-whether it's swimming at one of t.he reservoirs, fishing downstream of Gavins Point, boat- ing on the reservoirs, or camping, recreation is a big business on the lower river and it does add to tourism at both the reservoir sites and on the downstream river. The impacts from recreation, we also at times have to try to maintain constant levels on the lower river for duck blinds that are set up where they set their decoys out. We try to accommodate that, but it is not our major purpose. Looking at the impacts of recreation on flood con- trol, there are no impacts because releases are cut back when floods do occur. Hydropower generation-re- lease fluctuations for peaking may conflict with fishing and boating below the reservoirs. Endangered spe- cies-although not significant on the reservoirs, rec- reational use of the river sandbars downstream can be detrimental to the tern and plover. Last year they found that some of the people who were using some of the sandbars had done some damage to the tern nests with fIreworks. So recreation can be detrimental on the sandbar areas. Fish and wildlife is no signifIcant impact. Water supply and irrigation and recreation has no significant impact. WATER SUPPLY AND WATER QUALITY Water intakes, like Duane showed at MUD and this, although very hard to see, is one of the power plants in Sioux City. They did come close to having a problem at MUD. They also came close at the Neil North Plant to having an intake problem when we had that ice jam below Gavins Point this year. Impacts at the current level of water supply is not great. If we look at flood control we do maintain min- imum releases from most our reservoirs that facilitate water supply and water quality, such as the 6,000 cfs minimum from Gavins Point. There is no significant impact to hydropower, irrigation or fIsh and wildlife 35