HDR led the design for a $105 million improvement project at the Army Base Treatment Plant in Norfolk, Va., for the Hampton Roads Sanitation District (HRSD). The project’s goals were threefold: improve nutrient removal, upgrade aging equipment and install a plant-wide distributed control system. The plant received the National Association of Clean Water Agencies’ (NACWA) Platinum Award for 27 years of National Pollutant Discharge Elimination System permit compliance. The Army Base Treatment Plant holds the record for the longest time period to qualify for such an award from NACWA.
The improvements include a new preliminary treatment facility with fine screens, raw wastewater influent pumps and grit removal equipment. Additionally, new biological process tanks will house operation of a five-stage nitrification/denitrification process with biological phosphorous removal. These upgrades will help the plant meet an annual average effluent limit of 5 mg/L total nitrogen and 1 mg/L total phosphorous. To account for potential permit changes, the upgrade also will accommodate the future addition of effluent filters to meet a possible limit of 3 mg/L total nitrogen and 0.3 mg/L
The project began in 2008 and is scheduled for completion in March 2015. Throughout the duration of the project, plant operations continued, continually meeting effluent limits throughout the process. To accommodate additional treatment processes while maintaining plant operations on the congested construction site, HDR and HRSD developed a memorandum of understanding with the neighboring Port Authority to give the team additional land access for construction.
“One important accomplishment is the team’s efforts to meet permit through this difficult project,” said Bruce Husselbee, P.E., director of engineering for HRSD. “I think the plant staff, HDR and the contractor are to be given credit for accomplishing