GARRISON LAKE REHABILITATION PROJECT
Port Orford, OR

Significant beach erosion occurred along the coast of Oregon during the 1997-98 El Niño and 1998-99 La Niña winters due to the occurrence of several large storm wave events, coincident with high ocean water levels. The erosion was particularly severe at Garrison Lake, a small freshwater lake that is separated from the Pacific Ocean by a narrow barrier beach. The Garrison Lake Rehabilitation Study was undertaken to determine the causes of beach and dune erosion that have led to lake flooding and salt water intrusion. The objectives of this study were to determine the physical processes controlling Garrison Lake flooding, ocean shoreline changes, dune deterioration, and lake salt-water intrusions and to develop feasible alternatives and recommend the preferred alternative to address the project issues.

Coast & Harbor Engineering performed the following project tasks:

		Historical data and literature review
		Developed wind and wave climate statistics
		Performed 2-dimensional spectral wave transformation modeling to evaluate wave climate at the site for various storm conditions