Membrane Filtration Facility - A Model in Sustainable Water Infrastructure
Green Design Creates Big Savings
Aqua Maine, Inc. recently celebrated the completion of its newly expanded $7.2 million water filtration plant in Rockport. The Mirror Lake Water Treatment Facility serves a population of approximately 25,000 people in several nearby communities.
Meeting New Regulations
The pristine water supply of Mirror Lake has, to date, met all the regulatory requirements for public drinking water without filtration because of the excellent quality of the water in the lake. New regulations issued by the Environmental Protection Agency under the Safe Drinking Water Act require further treatment for the Mirror Lake system beyond it’s current process.
Filtration of Microbiological Pathogens
All water systems in the U.S. must provide specific treatment for cryptosporidium, a chlorine-resistant microbiological pathogen that has been the cause of waterborne disease outbreaks in other states. Additionally, the new regulations further restrict disinfection by-products in the water distribution system.
Wright-Pierce was retained by Aqua Maine, Inc., to permit, pilot test, select equipment, and design the first membrane filtration facility for a public water supply in the state of Maine. Following extensive pilot testing, Pall Corporation’s microfiltration membranes were selected for the facility upgrade.
Membrane Filtration — The Sustainable Solutions
- Ability to capture natural organic material as well as all other particles, including bacteria and protozoa.
- Requires a relatively small footprint and a small building.
- Highly efficient, offering low operating and maintenance costs in comparison with other filtration technologies.
- No chemical addition needed prior to the filters, unlike conventional technologies.
Unique and Innovative Facility
The facility is unique from many perspectives, including the waste handling process. The 6 MGD facility treats all backwash waste on-site, with a lagoon system to separate particulates from the waste stream. Solids separation is accomplished via filtration and solids settling following the addition of a coagulant. Water treated in the lagoon system is recycled back to the head of the plant, creating a zero waste discharge facility.
The new equipment is housed in a building addition to the existing disinfection facility. As part of the upgrade, renovations were completed to the SCADA and electrical systems. A construction phasing plan was developed to maintain the facility’s 24-hour operation during construction and commissioning. This was critical to successful project execution.
Green Design and Energy Savings
The building addition is designed to LEED standards for commercial structures. It features a solar thermal and photovoltaic solar system that helps offset the electrical cost of heating the chemical solutions required for the daily membrane cleaning cycle.