Wisconsin River Report - May 16, 2003

Wisconsin River Report

May 16, 2003

Wisconsin Valley Improvement Company

2301 North Third Street

Wausau, WI 54403

For more information contact Sam Morgan

Phone: 715.848.2976, ex 301

Email: morgan@wvic.com

More Heavy Rains Produce Highest River Flows of the Year

Heavy rains over the recent Mother’s Day weekend pushed river flows to their highest levels of the year according to Wisconsin Valley Improvement Company of Wausau. Rainfall totals for the weekend storm averaged 2.9 inches in the northern basin above Tomahawk and 2.3 inches in the central basin between Tomahawk and Wisconsin Rapids. The heaviest rains occurred along the border of Lincoln and Oneida counties where over 3 inches was reported. The recent storms pushed the total precipitation for the year in the northern basin to 10.2 inches, 2.4 inches or 30% above normal. Total precipitation thus far in 2003 in the central basin of 9.7 inches is 1.8 inches or 23% above normal.

River flows rose rapidly after the rains and approached the 5-year flood level at many locations by Tuesday. The flow of the Wisconsin River at Merrill reached 17,600 cubic feet per second (cfs), just short of the 5-year flood level of 18,600 cfs. At Rothschild the flow of the Wisconsin peaked at 35,500 cfs, also just short of the 5-year flood level of 38,300 cfs. Farther downstream at Wisconsin Rapids where the 5-year flood is 46,400 cfs, the peak flow this week reached 43,000 cfs. The flows did not reach damaging levels and dropped steadily after the Tuesday peaks. By Friday flows at most locations had fallen to less than 50% of their previous levels.

The Rainbow Reservoir near Lake Tomahawk rose to the full mark during the past week. The Willow Reservoir near Hazelhurst also filled rapidly and is now only 1 foot below full. Willow is expected to reach the full mark in the upcoming week. The other three of WVIC’s five major reservoirs; Rice (Nokomis), Spirit, and Eau Pleine remain full. Overall storage in the reservoir system rose 5% last week to 90% of capacity.

While rainfall has been well above normal, temperatures were below normal again last week, especially in the southern valley where the weekly average temperature of 53 degrees was 8 degrees below normal. Water temperatures in the Wisconsin River held fairly steady at 52 to 55 degrees.

Reservoir Water Levels			River Flow			Precipitation
Location	Feet Below Max	Weekly Change (Ft.)	Location	Weekly Average (cfs)	Monthly Normal (cfs)	Location	This Week (In.)	Annual Total (In.)	+/- Annual Normal
Rainbow	0.3	+0.5	Eagle River	N/A	618	Upper Basin	2.87	10.23	+2.35
Willow	1.2	+1.9	Tomahawk	3,715		Central Basin	2.26	9.67	+1.79
Rice	0.3	N/C	Merrill	10,233	3,100	Temperature
Spirit	0.3	-0.2	Rothschild	17,272		Location	Ave.	Normal	+/-
Eau Pleine	0.1	N/C	St. Point	23,104		Willow Reservoir	51	52	-1
Reservoir Storage			Wis. Rapids	23,468	6,492	Wausau	54	57	-3
Northern	86%	+6%	Petenwell	23,304		Prairie du Chien	53	61	-8
Overall	90%	+5%	Muscoda	17,779	12,353

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