Upper Monongahela River Planning Basin Sewage Facilities Planning Study
Sewage Facility Planning Study

Schematic of Upper Monongahela Basin Study Area

Client: Allegheny County Sanitary Authority (ALCOSAN) /
Hazen & Sawyer, PC
Location: Allegheny County, PA

As part of Allegheny County's Federal EPA Consent Decree mandated comprehensive regional wet weather planning effort, ALCOSAN awarded the Hazen & Sawyer / LSSE Team the Upper Monongahela Basin Sewage Facilities Planning Wet-Weather project in December 2007.

The basin includes 20 Allegheny County municipalities and encompasses approximately 30.5 square miles.

LSSE shared responsibility for completion of the four year evaluation including the following tasks:

  • Existing Conditions Evaluation
  • Hydrologic & Hydraulic (H&H) Modeling
  • Preliminary Alternatives Screening
  • Development of analysis tool for sizing and siting various wet weather facilities including storage, high rate clarification, vortex separation, retention treatment basins, secondary treatment and screening/disinfection facilities ranging from 1.0 MGD to 150 MGD
  • Alternatives Feasibility/Present Worth Analysis
  • Draft Facilities Plan Report
  • Final Facilities Plan Report
  • Public Participation and Municipal Outreach
  • Coordination with municipal engineers from 20 affected municipalities