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In comparison to many other area lakes, Big Chapman Lake possesses relatively good water quality. This water quality provides lake residents with an outstanding natural resource capable of supporting a wide variety of uses. Excellent water quality also increases property values around the lake. Because it is usually less costly to maintain lake water quality than it is to restore it once it becomes degraded and because it often takes a long period of time to restore a degraded lake, efforts to maintain the water quality of Big Chapman Lake should receive the highest priority in any watershed management plan. Specifically, management efforts should focus on the Crooked Creek subwatershed where elevated loads of sediment were identified. Management efforts applied to Big Chapman Lake will also improve Little Chapman Lake since its water discharges to Little Chapman.
Secondary priority should be given to treating watershed issues in the subwatersheds that discharge directly to Little Chapman. Specifically, management efforts should focus on the Lozier's Creek and Arrowhead Drain subwatersheds where high pollutant loadings were identified. Management techniques would include watershed BMP's wetland restoration, and bank and channel stabilization. Efforts to control loading should occur before any dredging of the lakes occurs. If the watershed is not managed first, dredging will need to be repeated and thus would not be very cost effective or permissible by the regulatory agencies.
Little Chapman suffers from poorer water quality than Big Chapman Lake. Fortunately, successful restoration of Little Chapman Lake's water quality may be achieved more quickly given its relatively shorter hydraulic residence time. A short residence time means the lake is regularly flushed with runoff from the watershed. When this watershed runoff contains a high concentration of pollutants, the lake receives regular inputs of these pollutants. If improvements are made in the watershed to reduce pollutant loads, the lake with a shorter residence time will have a speedier recovery than a lake with a longer residence time since it is continually flushed with clean water.
In-lake treatments to manage internal phosphorus loading, such as an alum treatment, should receive a lower priority than watershed treatments for both lakes. In-lake treatments are often more effective once external phosphorus loading has been controlled. In addition, the relatively short residence time of Little Chapman Lake suggests an alum treatment will be less effective in that lake. Thus, management efforts should focus on the watershed before allocating funds to in-lake treatments.
Based on this rationale, below is a prioritized list of management recommendations based upon current conditions. These conditions may change as land and lake use changes.
Implement bank and channel erosion control techniques along the lower portions of Crooked Creek to stabilize the channel and reduce sediment and nutrient loading to Big Chapman Lake. (Foundation Project Completed 2003)
Work with the Soil and Water Conservation District (SWCD) office, the surveyor's office, and landowners to install BMP's or restore wetlands in the Crooked Creek subwatershed. Work with SWCD and landowners to place agricultural land in CRP where possible or utilize conservation tillage methods.
Work with the developer of the (GreyStone residential development) to ensure the best possible storm water filtration and volume reduction techniques are being utilized.
Work with SWCD office, surveyor's office, and landowners to install BMP's or restore wetlands in the Lozier's Creek subwatershed. Work with SWCD and landowners to place agricultural land in CRP where possible or utilize conservation tillage methods.
Implement bank and channels erosion control techniques along Arrowhead Park Drain to stabilize the channel and reduce sediment and nutrient loading to Little Chapman Lake. (Foundation Project Contracted 2004)
Homeowner recommendations:
A) Use only phosphorus-free fertilizers. B) Consider natural stone or aquatic vegetation to protect shoreline from erosion instead of concrete seawalls; consider planting native vegetation in front of existing seawalls. C) Examine all drains that lead from roads, driveways or rooftops to the lake; consider alternate routes for these drains that would filter pollutants before it reaches the lakes. D) Keep organic debris such as lawn clippings, leaves, or animal waste out of the water. E) Use idle speeds in shallow water to limit prop wash, and mark those areas with buoys.
Consider installing a sanitary sewer system around the lakes. At a minimum, maintain existing septic systems and upgrade any systems as needed. Consider using wastewater wetlands in lieu of septic systems as these provide greater treatment of effluent than traditional septic systems.
Develop a recreational use management plan to address current use conflicts and balance these conflicts in a fair and democratic manner.
Work with local authorities to develop a zoning Master Plan for the watershed.
Fit direct storm water drain pipes with catch basins at a minimum. Consider installing storm water filters to trap sediment and remove pollutants from runoff.
Develop an aquatic plant management plan that comprehensively addresses control of invasive species, the issue of phosphorus created by decomposing plants, and the importance of preserving and promoting native plants, water quality, fish, and aquatic invertebrate habitat.
Controlling external phosphorus loading may be sufficient to control phosphorus concentration in the lakes.
Once external sediment loading is controlled, consider dredging selected areas (mouth of the Arrowhead Park Drain, mouth of Crooked Creek, etc.) to improve recreational use of the lakes.
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