Shoreland Erosion |
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Flooding the Chippewa Flowage, as in any impoundment, produced a condition of disequilibrium, opening up virgin shoreland to attack by waves. The flowage shoreline is especially susceptible due to its highly erodible, sandy soils and underlying unconsolidated glacial deposits and rolling topography. The continuing wave impact and erosion at the base of the sandy shoreland banks in the flowage prevents stabilization of those slopes, and perpetuates the disequilibrium condition by continually undercutting them. (Ice effects on the banks are not a significant erosion factor here because of the flowage’s winter drawdown.) It is therefore no surprise that bank erosion in common, and is especially evident wherever wind or boat generated waves impact steep, sandy slopes. Over the years, many small islands have been eroded away. (Chippewa Flowage Joint Agency Management Plan, August 2000) |
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Water Chemistry |
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The water chemistry of the flowage can generally be described as soft, near-neutral pH and stained. The water’s chemistry (particularly alkalinity and total phosphorus) indicates the flowage should support relatively low levels of organic production. An interesting feature of the flowage is a noticeable dichotomy in water clarity between its east and west basins. Water in the east basin is more darkly stained due to the direct influence of drainage from the Chippewa River system. The flowage’s west basin is clearer because it contains several natural groundwater fed lakes (Chief, Scott, and Crane) and clearer feeder streams. Some pools or bays become isolated by the winter drawdown, and low dissolved oxygen levels can become critical for fish survival in several locations. (Chippewa Flowage Joint Agency Management Plan, August 2000) |
