Upgrades to facility reduce energy consumption by 40% and position it to meet future nutrient removal standards
The American Council of Engineering Companies (ACEC) of Maine presented Wright-Pierce with an Honor Award for the Falmouth, Maine, Water Pollution Control Facility (WPCF) upgrade project at the recent annual 2009 Engineering Excellence Awards ceremony. The Honor Award recognizes engineering firms for projects that epitomize quality, innovation, value and client satisfaction.
The Falmouth WPCF was an aging wastewater treatment facility located on an environmentally sensitive site in a fast-growing coastal area in Southern Maine. In order to accommodate residential and commercial growth, and address increasingly stringent discharge standards, a system upgrade was required. This posed significant environmental challenges because the facility is in the Casco Bay watershed, one of the 28 "Estuaries of National Significance" as designated by the U.S. Environmental Protection Agency (EPA).
Faced with major site constraints, Wright-Pierce conceived a design that incorporated significant existing infrastructure into the new treatment scheme, saving the town hundreds of thousands of dollars in construction cost and capitalizing on past investments. The new treatment system employed an anaerobic-anoxic-oxic process with a biological selector designed to improve present day water quality characteristics and provide for advanced nutrient removal.
The result is a facility poised to serve the future sewered growth needs of the community and one that produces exceptional quality effluent. Treated effluent efficiency has improved by 40%, and nutrient removal is meeting the design goals of 8 mg/L total nitrogen and 1 m/L phosphorous. Space has been preserved within the process configuration to allow for easy expansion should more stringent requirements be established in the long term. The upgraded facility is one of only a few advanced treatment facilities in Maine positioned to meet future nutrient discharge standards.
Along with increased treatment efficiency and advanced nutrient removal, the upgrades have reduced monthly electrical consumption on average by 40%. In addition, this $7 million facility was constructed under the original contractors bid price, highly unusual in a major retrofit project.
"The Falmouth WPCF upgrade project is a success story. It's a municipal project that has incorporated sustainable design elements that have resulted in operational costs savings," stated Paul Birkel, vice president and principal-in-charge of the Falmouth project. "The adapted facility is now 40% more efficient both in treatment capability and energy use; it's designed to meet increasing discharge standards of the future; and it's accomplishing all of this while using less chemical in the treatment process."