The Easton Area Joint Sewer Authority (EAJSA) provides wastewater conveyance and treatment for its member municipalities in the Easton area of Northampton County.  The EAJSA member municipalities are:  the City of Easton (City), the Borough of West Easton, the Township of Forks, the Township of Palmer, the Borough of Tatamy and the Borough of Wilson.  The EAJSA also treats wastewater from the following non-member municipalities: Townships of Williams, Lower Nazareth and Bethlehem and the Borough of Glendon.  The EAJSA has a long term lease with the City for management of the wastewater plant, three large pumping stations and force mains and has an agreement with the City to provide staff for operation of these facilities.  

The EAJSA has also constructed its own sewage facilities, is responsible for common lines in the service area, the industrial pretreatment program in the service area and is the NPDES permit holder.  The plant was originally constructed in the early 1950s and major renovation projects were undertaken in 1978, 1988, 1998 and during the last five years. The plant is permitted for a wastewater flow of 10.0 mgd and an average influent organic loading of 20,000 pounds of BOD ₅ per day, employs physical and biological processes to achieve the required treatment levels.  

The plant's treatment process consists of grit removal and screening, primary clarification, secondary biological treatment through an oxidation ditch process, secondary clarification, disinfection using sodium hypochlorite and dechlorination using sodium bisulfite.  Sludge is handled through two stage anaerobic digestion.  Primary sludge is pumped directly to the digesters.  Secondary (or waste activated) sludge is thickened by a gravity belt thickener prior to digestion.  All digested sludge is dewatered by centrifuges.  The dewatered sludge is then landfilled.