Greater Lawrence Sanitary District
Location: 
North Andover
Technology: 
Anaerobic Digestion

The Greater Lawrence Sanitary District (GLSD) operates a wastewater treatment plant that serves six communities (Lawrence, Methuen, Andover, North Andover, Dracut and Salem, NH).  With the financial assistance of MassCEC, the Department of Energy Resources, the Department of Environmental Protecton and National Grid, GLSD is upgrading its plant to enable it to accept liquefied food wastes into three existing anaerobic digesters, build a fourth digester, and install a 3.1 megawatt combined-heat-and-power system.  The upgrades will also enable GLSD to self-power critical operations in the event of a blackout.  Anaerobic digestion is a biological process that converts organic matter to a gas that can be used to generate energy.  The GLSD project will provide an alternative to landfilling or incinerating food waste, dramatically reduce the plant’s electricity purchases from the grid, reduce greenhouse gas emissions and prevent the discharge of raw sewage to the Merrimack River during power outages.  Construction is underway with completion expected in 2018.