Design of Replacement Wastewater Pump Stations

The purpose of this study is to evaluate the hydraulic requirement(s) and life cycle costs to determine the best option (configuration) for a new pump station for serving the northwestern service area of the Orange County Sanitation District.
The new wastewater pump station is to replace two aging pump stations, Westside and Seal Beach pump stations. The new station is to be built adjacent to the existing Seal Beach PS. The design will accommodate current as well as future (year 2040) projected flows. Current flows to Westside PS range from 1.60 MGD to 9.70 MGD. Future flows are projected to reach a peak wet weather flow of 16.50 MGD. Current flows to Seal Beach PS (including those from Westside PS) range from 2.50 MGD to 19.90 MGD. Future flows are projected to reach a peak wet weather flow of 32.5 MGD.

Two configurations for the new pump station are to be considered, a single wet well – single pump set (previously studied) and dual wet wells – dual pump sets.

In addition to the new pump station and its force main(s), the study is to address the reconfiguration of the upstream sanitary sewers (gravity) feeding the existing stations.