Wastewater Treatment Facility Upgrade – Rollinsford

Rollinsford, New Hampshire

Client: Town of Rollinsford, New Hampshire


  • Construction Administration
  • Design

Project Summary

Hoyle, Tanner completed the upgrade of the existing wastewater treatment facility. The upgrade enabled the wastewater treatment facility to meet the effluent limitations required in the new NPDES permit which was issued by the EPA. Based on the results of recent TMDL studies of the Salmon Falls River, the District was required to meet a phosphorus concentration limit (average monthly) of 1.0 mg/l and a phosphorus mass loading limit of 1.2 pounds per day (average monthly). Hoyle, Tanner completed study, design phase engineering services, and construction phase services for this project. Several alternatives were evaluated, including innovative and alternative technologies, for the upgrade of the treatment process. During design, several alternatives for receiving/processing septage were evaluated. Hoyle, Tanner selected and implemented a biological phosphorus removal (BPR) process utilizing the anaerobic/oxic (A/O) configuration. Chemical addition capable of feeding alum or poly-aluminum chloride (PACI) was also included for both trimming and backup.

Click on thumbnail to view