The Abbottstown-Paradise Joint Sewer Authority was incorporated in 1973 and utilized a continuous flow activated sludge system with an average daily design flow of 0.21 MGD. At that time the plant was only required to reduce total suspended solids (TSS) and effuent ammonia to required levels to serve the area population of about 2000. Due to urban growth and increased storm flow runoffs, the plant was in need of an expansion and upgrade by the late 1990s. The existing plant had reached its hydraulic capacity and was subject to solids carryover during high flows. The plant was also having difficulty in meeting its ammonia limits. To find a solution to its problem, Abbottstown turned to the local consultant, C.S. Davidson, Inc. to perform an evaluation on upgrade and expansion options and provide a recommendation.