HINSDALE WASTEWATER TREATMENT PLANT

WWTP History (Written 9/20/2018) The Hinsdale Wastewater Treatment Plant is located at 120 River Road. Construction of the plant started in April of 1978 and the Plant went into operation on October 22, 1979. The total cost was 1.9 Million Dollars with the Federal Government paying 75%, the State Government paying 20% and the Hinsdale Sewer Users paying the final 5% with a 30 year bond. It is an Extended Aeration Plant that includes a grit removal system, comminutor, oxidation ditches with rotors for aeration, secondary clarifiers, a chlorination / de-chlorination tank, an aerated sludge holding tank and sand drying beds that are no longer used and have been converted into a storage area. The plant is staffed by two full time employees that share being on-call to provide 24/7/365 coverage. The plant’s design capacity is 0.3 million gallons per day (MGD). The Town is issued an NPDES Discharge Permit from the EPA every five years that regulates what the WWTP must comply with to discharge its effluent to the Asheulot River. In 2016 the plant averaged 0.1515 MGD with a total rainfall of 36.3 inches for the year. In 2017 the plant averaged 0.1852 MGD with a total rainfall of 50.8 inches for the year. The plant experiences significant infiltration problems during the spring and times of high water table where the inflows at the plant can be double the plant’s capacity. Sump pumps are also suspected to contribute to the plants infiltration problem. The collection system consists of approximately 9 miles of lines servicing in the area of 600 units in the downtown village area only, with the majority of it being constructed in the 1930s. The collection system was extended with Pump Stations being installed on Canal Street in 1988 and on Glen Street in 1989. The State placed a moratorium on new connections to the system on November 27, 2006 due to Inflows at the plant consistently being over 80% of the design flow. The department then developed and instituted an Infiltration and Inflow (I&I) Program to help inform our customers of the problems caused by the I&I issues and how they can help. It also initiated inspections of properties to locate illegal sump pumps and drains. The department has been doing some PVC Lining of some bad sections of main and doing smaller projects to help reduce the infiltration problems. Two major projects have also been completed. In 2007 the collection system on Canal Street was replaced at a cost of over $400,000 and in 2010 the collection systems on Main Street, Stearns Court and Fitzgerald Court were replaced or repaired at a cost of over $600,000. Both of these projects were assisted financially by Grants with User Fees funding the remainder. The State rescinded the moratorium on new connections to the system on February 1, 2011. Some major projects that have been done at the WWTP include the influent pumps and control system being replaced in 1997 for $77,000. The sludge pumps and controls were replaced in 2001 for $38,000. A new rubber roof was installed on the Operations Building in 2006 for $12,000. In 2010 the emergency generator was replaced for $37,000 and the 1982 dump truck and plow were replaced for $40,000. Both of these projects were assisted financially by Grants. In 2018 we installed standing seam metal roofing on the old drying beds structure which is now utilized as a storage garage for several town departments at a cost of $52,750.