Natural Shorelines

WATERSHED

A “watershed” is actually a drainage basin. It is an area of land where water from rain or snow drains downhill into a body of water, such as Powers Lake. The drainage basin acts like a funnel, collecting all the water within the area and directing it into the lake. Having an effective Watershed Management Program is essential to maintaining a healthy lake. The DPL has demonstrated its devotion to this cause by purchasing properties in recent years in order to enhance our watershed’s effectiveness and preserve water quality. The District has also expended considerable effort and research to implement a comprehensive Lake Management Plan.

SHORELINE CONDITIONS

Erosion of the Powers Lake shoreline results in the loss of land, damage to lakeside facilities, and interference with access to, and use of, the shoreline. Such erosion is primarily caused by waves generated by wind, by power boating activities, and by ice action. A survey of Powers Lake shoreline conditions was conducted in June of 1990 to identify the type and condition of existing shoreline protection structures and to evaluate the stability of unprotected shoreline areas.

A total of 133 shore protection structures were found to be located on the Powers Lake shoreline: 71 bulkheads, 33 revetments (riprap), and 29 beaches. A bulkhead is a vertical retaining wall usually constructed of concrete, steel sheet piling, or timber. A revetment is a layer or layers of armor stone underlain by filter cloth or gravel bedding. Beaches may contain natural sand or gravel deposits or may be artifically nourished. These structures protect about 13,070 feet of shoreline, or about 47 percent of the total shoreline length of Powers Lake.

Of the 53 percent of the Powers Lake shoreline that was not protected by structures, 89 percent was found to be stable and well vegetated.

SHORELINE PROTECTION

The recommended shoreline management measure in all the areas designated as environmentally valuable and in adjacent wetland and wildlife habitat is to revegetate about 1,125 feet of unstable, unprotected shoreline. About 6,975 feet of shoreline within environmentally valuable areas was protected by structures in 1990. Is is recommended that these structures be maintained by using selected types of natural vegetation or appropriate structural measures. Recommended shoreline protection measures outside the environmentally valuable areas for about 550 feet of unstable, unprotected shoreline include revegetation and the establishment of such structures as revetments or bulkheads.