MONITORING 1999 AND 2001 NOURISHMENT SAND MOVEMENT ON THE PRESQUE ISLE PENINSULA , LAKE ERIE AT ERIE, PENNSYLVANIA - BEACH 10 TO GULL POINT

The present study extends to two full years the monitoring study reported at the 1999 NEGSA for the fall and winter of 1999 –2000. The area from the beach offshore to a depth of 8 m (19 ft) was mapped periodically from October 26, 1999 through November 1, 2001. Shoreline changes and volumetric analysis of subdivisions of the map area provide detailed information of offshore and along-shore movement of the 54,000 tons nourishment sand in 1999-2000 and 37,500 tons of nourishment in 2001. From 1989 to1992 the US Army Corps of Engineers Presque Isle Erosion Control Project constructed fifty-two segmented, offshore breakwaters with along the Lake Erie perimeter of the 11 km (7mi) recurved spit which is the location of Presque Isle State Park (PISP), Erie, PA. The purpose of the $23.8 million breakwater construction was to reduce the volume and expense of beach nourishment, which had often exceeded $ 1,000,000 yearly prior to construction. Assuming success the annual nourishment for 1993 to 1998 was reduced from 228,000 to 86,000 tons overall (38% of the pre-construction volume). Insufficient growth of the Gull Point area signaled inadequate nourishment and instigated the massive sand nourishment from July - September 1999. Additional nourishment was instigated in 2001 by excessive erosion at the end of the breakwater sequence. This study monitors the fate of nourishment sand placed at Beach 10, which marks the updrift end of Gull Point. Ten north-to-south transects were established at Beach 10, three within the 340 m (1120 ft) nourishment area and seven in the 600 m (1800 ft) area to the east (downdrift). The exposed beach extending offshore to a depth of 8 m (19 ft) was mapped using a Lietz Set-5 Total Station infrared laser theodolite and a boat equipped with a Lowrance X-16 precision depth recorder. Detailed topographic contour maps and profiles will be generated using Lietz’s proprietary Sokkia Map and Contours software. Sokkia Volumes software will be used to calculate volume changes over time by comparing the surfaces thus mapped. ArcView GIS Spatial Analyst and 3-D Analyst will also be used.