Frederick WWTP ENR Upgrade

Improving nutrient removal and plant operations.

Frederick, MD
Delivery Method
City of Frederick, MD
Year Complete

Project Overview

This project incorporated a comprehensive overhaul of the existing 8-mgd wastewater treatment plant to improve nutrient removal and convert from a chlorine/sulfur dioxide to a new UV disinfection system. Many areas of the existing plant were also upgraded to improve operations and replace aging equipment.

Several enhanced nutrient removal (ENR) upgrades were required to achieve new total nitrogen and phosphorous discharge limits. Work included bioreactor upgrades and new aeration systems, intermediate pumping station, denitrification filter complex, methanol storage/feed system and bioaugmentation reactor for centrate pretreatment. Extensive construction sequencing and temporary bypass piping, pumping and equipment were required to maintain the treatment processes during construction.

PC worked collaboratively with the plant operations staff and GHD Consulting Engineers to successfully startup the facility during the wettest year on record.


Total Construction Project Value


MGD Wastewater Treatment Facility


Contract Value Self-Performed by PC