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Base flow, Floods, and Sediment Loads of Lake Superior Tributaries. By Faith A. Fitzpatrick U.S. Geological Survey, WRD, Middleton, Wis. Base Flow, Floods, and Sediment Loads. How do tributaries vary in these characteristics because of geology geomorphology, and land use?
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Base flow, Floods, and Sediment Loads of Lake Superior Tributaries By Faith A. Fitzpatrick U.S. Geological Survey, WRD, Middleton, Wis.
Base Flow, Floods, and Sediment Loads How do tributaries vary in these characteristics because of geology geomorphology, and land use? What implications do these natural and human-caused variations have for fisheries management and restoration?
Peat Sand/gravel Other Clay Loam Washington Pigeon Knife St. Louis Tahquamenon Deer Trap Rock Au Train Sturgeon Fish Nemadji Bad Ontonagon White Bois Brule Montreal Whittlesey
Base flow – geologic setting • important
Base flow complexities…….. Baseflow, August 2002 (cubic feet per second) 0-0.10 10-19 0.1-10 Whittlesey Creek . # # t m # # . # # # # # # # # . # # #
Contributing Area from Deep Flow System Sioux River Whittlesey “watershed” Whittlesey Creek North Fish Creek
U.S. Suspended Sediment Contributions to Lake Superior Average Daily Loads (Robertson, 1996)
Post-settlement annual sediment budget (metric tons per year) North Fish Creek
Sediment—Importance of Bed Load and Yield Descriptions Suspended load Total load (kg/ha/yr) (kg/ha/yr) Bad River 1,030 no data Fish Creek 1,450 4,380 Suspended load Total load (dump trucks/day) (dump trucks/day) Bad River 58 176?? Fish Creek 2 5
North Fish Creek—Floods 2 times and sediment loads 2.5 times pre-settlement rates
Estimated bankfull discharge, m3/s 12 10 <1946 25 400 1995 4 60 0 meters 15 10 300 ALTITUDE (METERS) 1995 8 <1906 60 0 200 0 20 40 DISTANCE FROM MOUTH (KILOMETERS) Brook trout originally found throughout entire stream Limited sustained brook trout in headwaters
Habitat Protection and Restoration: • Focus efforts on reducing watershed runoff and erosion-control in upper main stem • Use restoration techniques similar to those for urban streams–keep/restore pre-development storm hydrographs
Rehabilitation techniques geared toward reducing watershed runoff and bank erosion • Detention, infiltration basins in headwaters • Increase forest cover in watershed • Grade control structures in upper main stem • Bank protection in upper main stem • Large woody debris • Beaver • (Do nothing)
Acknowledgments • This presentation contains results from cooperative studies among the Wisconsin Department of Natural Resources, University of Wisconsin-Madison, Bayfield County, U.S. Fish and Wildlife Service, and the U.S. Geological Survey • Special thanks to Dennis Pratt (WDNR) and Dave Saad (USGS) for slide contribution