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Research about Bayfield County, Wisconsin

Source-linked reports with geographic coverage including Bayfield County, Wisconsin.

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Monitoring channel morphology and bluff erosion at two installations of flow-deflecting vanes, North Fish Creek, Wisconsin, 2000-03

Flow-deflecting vanes were installed in the streambed along two meander bends with eroding bluffs in 2000 and 2001 in the upper main stem of North Fish Creek, a tributary to Lake Superior in Wisconsin. About 45 vanes were arranged in 15 arrays at each site to deflect the flow away from the eroding toe or base of the bluff (outside of a bend) and toward the point bar (inside of a bend). Channel cross-section and bluff-erosion surveys were done and streamflow and stage were measured before, during, and after vane installation to monitor changes in channel morphology and bluff erosion in the context of hydrologic conditions. There were two large floods in the study area in spring 2001 (recurrence interval of approximately 100 years) and in spring 2002 (recurrence intervals of approximately 50 years). Some maintenance and replacement of vanes were needed after the floods. Most of the channel-morphology changes resulted from the large floods, and fewer changes resulted from near-bankfull or at-bankfull flows (one in October 2002 and four in April and May 2003). At the bluff located 16.4 river miles upstream of the creek mouth (site 16.4), the vanes deflected flow and caused the channel to migrate away from the base of the bluff and toward the point bar, allowing sediment to deposit along the bluff base. The 361-foot reach at site 16.4 had a net gain of 6,740 cubic feet of sediment over the entire monitoring period (2000?03). Deposition (10,660 cubic feet) occurred mainly along the base of the bluff in the downstream part of the bend. Erosion occurred at site 16.4 along the streambed, the point bar side of the channel, and along a midchannel bar (1,220, 1,610, and 1,090 cubic feet, respectively). Less channel migration was observed during 2001-03 at another bluff located 12.2 river miles upstream of the creek mouth (site 12.2), which had a net loss of sediment through the 439-foot reach of 2,800 cubic feet over the monitored time period. The main volume of sediment was lost from the bluff toe in the downstream part of the bend (7,100 cubic feet). Monitored channel-morphology changes at site 12.2 were less than at site 16.4, most likely because installation was done after the April 2001 flood, which caused major changes in channel morphology at site 16.4, and because the monitoring period was shorter than at site 16.4. Bluff-erosion data from both sites indicate that mass wasting and block failures from the bluff top occur episodically and will continue to occur for decades or more.

Wisconsin

Simulation of ground-water flow and rainfall runoff with emphasis on the effects of land cover, Whittlesey Creek, Bayfield County, Wisconsin, 1999-2001

The effects of land cover on flooding and base-flow characteristics of Whittlesey Creek, Bayfield County, Wis., were examined in a study that involved ground-water-flow and rainfall-runoff modeling. Field data were collected during 1999-2001 for synoptic base flow, streambed head and temperature, precipitation, continuous streamflow and stream stage, and other physical characteristics. Well logs provided data for potentiometric-surface altitudes and stratigraphic descriptions. Geologic, soil, hydrography, altitude, and historical land-cover data were compiled into a geographic information system and used in two ground-water-flow models (GFLOW and MODFLOW) and a rainfall-runoff model (SWAT). A deep ground-water system intersects Whittlesey Creek near the confluence with the North Fork, producing a steady base flow of 17?18 cubic feet per second. Upstream from the confluence, the creek has little or no base flow; flow is from surface runoff and a small amount of perched ground water. Most of the base flow to Whittlesey Creek originates as recharge through the permeable sands in the center of the Bayfield Peninsula to the northwest of the surface-water-contributing basin. Based on simulations, model-wide changes in recharge caused a proportional change in simulated base flow for Whittlesey Creek. Changing the simulated amount of recharge by 25 to 50 percent in only the ground-water-contributing area results in relatively small changes in base flow to Whittlesey Creek (about 2?11 percent). Simulated changes in land cover within the Whittlesey Creek surface-water-contributing basin would have minimal effects on base flow and average annual runoff, but flood peaks (based on daily mean flows on peak-flow days) could be affected. Based on the simulations, changing the basin land cover to a reforested condition results in a reduction in flood peaks of about 12 to 14 percent for up to a 100-yr flood. Changing the basin land cover to 25 percent urban land or returning basin land cover to the intensive row-crop agriculture of the 1920s results in flood peaks increasing by as much as 18 percent. The SWAT model is limited to a daily time step, which is adequate for describing the surface-water/ground-water interaction and percentage changes. It may not, however, be adequate in describing peak flow because the instantaneous peak flow in Whittlesey Creek during a flood can be more than twice the magnitude of the daily mean flow during that same flood. In addition, the storage and infiltration capacities of wetlands in the basin are not fully understood and need further study.

Wisconsin

Effects of historical land-cover changes on flooding and sedimentation, North Fish Creek, Wisconsin

North Fish Creek, a Wisconsin tributary to Lake Superior, is an important recreational fishery that is potentially limited by the loss of aquatic habitat caused by accelerated flooding and sedimentation. A study of the historical flooding and sedimentation characteristics of North Fish Creek was done to determine how North Fish Creek responded to human-caused changes in land cover since European settlement of the region in the 1870's. Geomorphic field evidence combined with hydrologic and sediment-transport modeling indicate that historical clear-cut logging, followed by agricultural activity, significantly altered the hydrologic and geomorphic conditions of North Fish Creek. The geomorphic responses to land-cover changes were especially sensitive to the location of the reaches along the main stem and on the timing of large floods. On the basis of geomorphic evidence in flood-plain deposits and abandoned channels, the size of floods and sediment loads also increased in North Fish Creek after conversion of forested land to cropland and pasture. Changes in channel characteristics were particularly noticeable after record floods in 1941 and 1946. The upper main stem channel bed eroded downward at least 3 meters and the channel capacity at least doubled after European settlement. In the lower stem, the post-settlement sedimentation rate on the flood plain and in the channel is 4 to 6 times pre-settlement rates. The water table also appears to be rising near the mouth of North Fish Creek, perhaps consistent with (1) elevated local streambed elevations caused by sedimentation and (2) a slow relative rise in the local level of Lake Superior due to crustal rebound from glaciation. Along a transitional reach of the main stem between the upper and lower main stem, there is evidence of accelerated flood-plain sedimentation initially following European settlement. Since at least the 1940's, however, the channel bed in the transitional reach has eroded about 1 meter and the channel capacity has at least doubled. Results from hydrologic and sediment-transport modeling indicate that modern flood peaks and sediment loads in North Fish Creek may be double that expected under pre-settlement forest cover. During maximum agricultural activity in the mid-1920's to mid-1930's, flood peaks probably were about 3 times larger and sediment loads were about 5 times larger than expected under pre-settlement forest cover. These results indicate that future changes from pasture or cropland to forest will help reduce flood peaks, thereby reducing erosion and sedimentation. The addition of detention basins (to decrease flood peaks) on tributaries to North Fish Creek, or bank and instream restoration (to decrease erosion) in the upper main stem, also may help reduce the contribution of sediment from the upper main stem to the transitional section and lower main stem of the creek.

Wisconsin

Sediment transport, particle size, and loads in North Fish Creek in Bayfield County, Wisconsin, water years 1990-91

North Fish Creek is underused as a trout and salmon hatchery despite its excellent water quality. The shifting-sand streambed in the lower 9 miles of the stream inhibits successful spawning and is a poor habitat for macroinvertebrates, the primary food for juvenile trout and salmon. To provide data necessary for evaluation of potential sand-loading-control practices, the U.S. Geological Survey determined total-sediment transport, particle size, and loads for three sites, designated A, B, and C, on North Fish Creek during water years 1990-91. At site C, the most upstream site, all sediment was transported as suspended sediment. The average annual total-sediment load during 1990- 91 was 479 tons. About 88 percent of the load was transported during periods of snowmelt or storm runoff. About 75 percent of the sediment load was silt- and clay-size particles; the remainder was sand. Total-sediment discharge was calculated by the modified-Einstein procedure to determine total sediment transport-rate relations for site A, the most downstream site, and for site B. Annual totalsediment load was 11,960 tons in water year 1990 and 18,430 tons in water year 1991 at site B. About 97 percent of the total load was transported during periods of snowmelt and storm runoff. About 60 percent of the total-sediment load was sand-size particles. Annual total-sediment loads were 20,690 tons and 33,100 tons in water years 1990 and 1991, respectively, at site A. About 67 percent of the total-sediment load was sand-size particles. Annual average streamflow, as indicated by flow in the Bois Brule River, was about 16 percent below average in water year 1990, and about 4 percent above average in water year 1991. There was little relation between watershed area and sediment loads for the three sites. The watershed of site C is about 41 percent of that of site A, but the sand load at site C was only 1 percent of that at site A. The watershed area between sites B and C is 40 percent of that above site A, but this area yielded 49 percent of the sand load at site A. Nineteen percent of the watershed above site A is between sites A and B, yet this area yielded about 50 percent of the sand load at site A.

Wisconsin

Water resources of the Apostle Islands National Lakeshore, northern Wisconsin

The Apostle Islands National Lakeshore consists of 21 islands, part of the Bayfield Peninsula, and the adjacent waters of Lake Superior. Selected water resources of the Apostle Islands National Lakeshore were assessed to aid the National Park Service in developing and managing the Lakeshore and to provide a data base against which future changes can be compared. This summary of water-resources data, collected by the U.S. Geological Survey during 1979-84, provides a qualitative description of selected hydrologic components of the Lakeshore. Streamflow in the Lakeshore area is characterized by typical seasonal fluctuations. Flow in Sand River at State Highway 13 ranged from 3.9 to 1,630 cubic feet per second. The recurrence interval of the maximum observed discharge was about 4 years. The minimum observed 7-day low flow was 3.86 cubic feet per second. The greatest concentrations of most chemical constituents in Bayfield Peninsula streams occurred during base flow. Annual sediment loads in Sand River at State Highway 13 ranged from 977 tons in 1980 water year to 24,600 tons in 1984 water year.The average annual sediment load transported by Bayfield Peninsula streams to the National Lakeshore area of Lake Superior is estimated to be 44,000 tons. Annual phosphorus loads ranged from 1,400 pounds in 1980 water year to 11,100 pounds in 1984 water year. The average annual phosphorus load transported by Bayfield Peninsula streams to the National Lakeshore area of Lake Superior is estimated to be 21,500 pounds. Few island streams flow perennially, but Oak Island streams generally yield more base-flow runoff than Stockton Island streams. The base flow of Oak Island streams is dominated by ground-water discharge, whereas Stockton Island stream base flow is sustained by seepage from wetlands and beaver ponds. There are two major lagoons in the Lakeshore, the Outer Island Lagoon's area is 53 acres and its maximum depth is 7 feet. Dominant inflow to the lagoon is from precipitation on its surface and seepage from an adjacent bog. Outflow during open-water periods is dominated by evaporation. Ground-water seepage from the lagoon toward Lake Superior occurs yearround. The lagoon's water is acidic and has low specific conductance and generally small concentrations of most chemical constituents. The Michigan Island Lagoon is about 4 acres in area and its maximum depth is 6.5 feet. The most significant sources of inflow appear to be precipitation and wave washover from Lake Superior. Water from four deep-water monitoring sites in Lake Superior revealed concentrations of total phosphorus, organic carbon, and recoverable mercury ranging from <0.01 to 0.02 milligrams per liter, 1.1 to 5.3 milligrams per liter and <0.1 to 0.1 micrograms per liter, respectively. Neither pesticide residues nor fecal coliform bacteria were detected in the water column. Total phosphorus concentrations in bottom sediment ranged from 50 to 470 milligrams per kilogram and were related directly to the percentage of fine-grained (< 0.0625 millimeters) sediment particles. Traces of only two pesticide residues- DDE and DDT were detected in sediment. The most abundant benthic macroinvertebrate was Pontoporeia affinis, which was found in densities of from 960 to 2,100 organisms per square meter. No adverse affects resulting from visitor use were detected in the shallow-water, heavy-use areas in Presque Isle Bay off Stockton Island or in the waters between Rocky and South Twin Islands. Phosphorus and organic-carbon concentrations were similar to those observed in the deep-water area; mercury was not detected in water from either area. Ground-water use in the National Lakeshore is primarily for consumption by Lakeshore visitors and employees. Of 14 wells constructed from 1979-84, 4 were finished in glacial sand and gravel, and 10 were finished in sandstone. Specific capacities ranged from 0.63 to 50 gallon per minute per foot. Average concentrations of dissolved solids are moderate and concentrations of heavy metals did not exceed Wisconsin's primary health standard.

Wisconsin