The Central Heating Plant (CHP) currently utilizes the effluent from the Amherst Waste Water Treatment Plant (reclaimed water) as boiler make-up water to produce steam for the campus and for the CHP cooling towers. To increase water conservation, and to maximize the capability of the existing Reclaimed Water Treatment Facility (RWTF), the CHP has submitted a Class A Reclaimed Water Application to the Massachusetts Department of Environmental Protection to use reclaimed water at the Commonwealth Honors College Residential Complex cooling towers as well.
The Amherst campus currently requires about 340 million gallons of water per year and the RWTF can process approximately 200,000 gallons of reclaimed water per day. Boiler water make-up for steam production utilizes the full capacity of the RWTF during the heating season. The addition of the cooling towers at the Commonwealth Honors College will maximize the reclaimed water capacity during the cooling season. This would result in a potential reduction of potable water consumption of 73 million gallons of water per year (21%).
History: Approximately twelve years ago the Town of Amherst Department of Public Utilities requested that UMass investigate ways to reuse the town’s Waste Water Treatment Plant’s effluent (reclaimed water) on campus. UMass commissioned a study to investigate the feasibility of reusing this effluent and confirmed that the reclaimed water was possible for boiler water make-up at the old power plant. The best path forward on this effort was to use proven technology – multi media filters, reverse osmosis membranes, and chlorination.
With approval from the Town of Amherst and the Massachusetts Department of Environmental Protection (MADEP), the University started utilizing reclaimed water in 2005. The water re-use initiative reduced potable water consumption by about 16%.
Source: UMass Amherst EH&S
This effort preceded new regulations that came out in 2009, the MADEP published Reclaimed Water Usage Permit Regulations - 310 CMR 20.00 and the MA Plumbing Board published Reclaimed Water Usage Permit Regulations - 248 CMR 10.00. Although reclaimed water has been used in various areas in other parts of the United States, the University on September 23, 2011, received the first Class C Reclaimed Water Permit for boiler make-up water, in Massachusetts through a joint effort with the University, the Town of Amherst and the MADEP Western and Boston regions.
In 2012, the University collaborated with the MADEP to expand our reclaimed water usage to include two cooling towers located at the Central Heating Plant. On April 25, 2013 we received the more stringent Class A and Class C Reclaimed Water Permit. As stated above, the University is now working with MADEP to expand our reclaimed water usage to include cooling towers located at the Commonwealth Honors Residential Complex. Upon approval of the modified Class A and Class C Reclaimed Water Permit, the CHP will utilize the full capacity of the current system.
The Town of Amherst Wastewater Treatment Plant takes the final treated wastewater from the City of Amherst's wastewater treatment plant, treats the water for use in the boilers, then feeds process water to the UMass steam plant. This alternative to using potable town water has resulted in big savings.
The plant was installed at a cost of $1.8 million and has a rated output of 250 gallons/minute. To commence the disinfected treatment water process, a chlorinated effluent is sent to a sand filter bank then to several final cartridge filters. These cartridge filters remove fine particles. The central feature of the plant, a bank of reverse osmosis (RO) membranes, filters the effluent. Lastly, the treated water is stored in an outside tank until the steam plant can use it. Typically, the steam plant uses the reclaimed water that very same day.
The effluent from the wastewater treatment plant is of better quality then the town water for industrial purposes, which results in the reduction of boiler "blowdowns" by about 10%. This reduction in boiler blow has resulted in roughly a 2% fuel reduction at the steam plant.