Sewer Pump Station Rehabilitation Package No. 11

St. Bernard Parish Government, Department of Public Works, Chalmette, LA

H. Davis Cole & Associates, LLC was tasked with this project which involves the provision of Design, Bidding, and Construction Phase services for the complete mechanical and electrical rehabilitation of twelve (12) sewer lift stations throughout the Parish of St. Bernard.

Because the stations were severely damaged by Hurricane Katrina, the construction of this project will be funded by the Federal Emergency Management Agency (FEMA) under the Public Assistance (PA) Program.

Construction of the Contract is being performed by Hemphill Construction Co., Inc. of Florence, MS. Construction is approximately 75% complete.

Unique to this project was the lack of As-Built drawings or any records on the pump stations as all records were destroyed by Katrina. Therefore, HDCA used several techniques to assertain the original pump station design point. These techniques included the analysis of the wet well volume versus minimum pump run times to estimate flows. Also, the minimum and maximum velocities within the existing force mains were calculated to establish a range or possible design flows. Finally, a comparison of the existing motor horsepower and discharge diameter was used to narrow the choice of possible pump curves. Using all three methods, the design flow for each station was established.