Allentown Collection System Evaluation. Allentown, Pennsylvania.

The objective of this project was to prepare a Corrective Action Plan for the City to remove SSOs. WR&A developed a model consisting of 1,500,000 linear feet of sewer ranging in size from 8 to 60 inches in diameter. The model was used to run a number of scenarios and potential improvements to arrive at alternatives which would eliminate the SSOs for a 10-year 24-hour storm. Flow equalization basins were tested at various locations to mitigate peak flows within the system. In areas where sewers were over capacity, parallel trunk sewers were recommended to reduce surcharging. The capacity of a pump station within the system was increased to allow additional flow to be removed from the gravity system. Various combinations of these improvements were modeled to determine the effective elimination of SSOs.