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(2) Rocky Mountain Snowmelt. .. The Rocky Mountain snow pack for the winter of 1997 - 1998 was average to below average. The South Platte River basin in Colorado had above average snow pack at the start of the season. The snow pack gained ground again in April, as several late season snowstorms added significant snow mass, Snow pack conditions are given in Table 3 below. The snowmelt in Colorado and in the other Rocky Mountain States was largely uneventful. Warm days were followed by tool nights, which allowed the snow to melt relatively slowly. Rain fell on basins where streams and rivers were already running high from seasonal snowmelt in the Missouri basin headwaters of Montana in June. The combination of the rainfall and the recession of the snowmelt runoff resulted in some flooding. TABLE 3 MOUNTAIN SNOW PACK MOISTURE AS A PERCENT OF NORMAL Upper Upper North Missouri Basin Yellowstone Platte South Platte Date Headwaters River Basin River Basin River Basin 8-Dec-97 81 82 76 110 21-Jan-98 97, 98 88 99 18-Feb-98 86 86 85 91 18-Mar-98 84 82 88 92 22-Apr-98 95 90 96 108 20-May-98 82 67 80 95 3-Jun-98 85 49 74 29 (3) Glacial lakes "Flood" The Waubay lakes area of South Dakota continued to remain under a threat of additional significant lake elevation increases at the end of July 1 998. The closed basin, which has historic drainage ties to the upper Big Sioux River basin, f lies between the Big Sioux, James, Minnesota and Red River watersheds a Above average precipitation since the early 1990s has resulted in a steady increase in lake levels to above record stages in the area around Waubay, South Dakota, and much , of eastern South Dakota. lowlands became sloughs, sloughs became lakes and lakes have grown and merged with other lakes across a wide area of eastern South Dakota. Farmland, homes, rail lines, county roads and highways have fallen victim to the water's 7