To all - more storm related clean water issues. The following is a press release just published regarding infiltration to a sewer line going to the treatment plant. It is different from the Riverkeeper’s alert last week of sewage possibly emanating from the storm water line near the Riverfront Park.
Press Release from the Office of the Mayor
October 4, 2011
CITY OF BEACON IDENTIFIES DAMAGE TO SANITARY SEWER LINE UNDER THE FISHKILL CREEK CAUSED BY HURRICANE IRENE – NO SEWAGE DETECTED ENTERING THE CREEK
The City of Beacon has informed NYSDEC and DCDOH of the recent discovery of additional flow into the City’s Sewage Treatment Plant (“STP”) from an inflow of water into the sanitary sewer line from the Fishkill Creek caused by Hurricane Irene. The City is aggressively investigating this issue to develop a corrective action plan to repair the damaged sewer pipe that flows under the Fishkill Creek.
After what was already one of the wettest Augusts on record, Hurricane Irene dumped 9.86 inches of rain on the City of Beacon from August 27 – 28. Then from September 5 – 8, the City received another 7.31 inches of rain from Tropical Storm Lee. In fact, the City received 18.99 inches of rain in August, 2011 and 14.79 inches of rain in September.
During this period, the City continued to monitor sewage flows at its STP and at several locations within the collection system. The City observed that flows were taking longer than usual to return to typical “dry-weather” levels, but initially attributed this phenomenon to the historically high rainfall conditions just experienced. However, as sewage flows at the STP remained high, the City’s consultants analyzed the collection-system metering data and determined that an unusual inflow of approximately 3 million gallons per day was occurring along the South Interceptor. City staff immediately began a series of investigative measures to identify the source of this additional inflow, including a series of dye testing and investigation of manholes to find inflows. On September 30, 2011, the City concluded that water from the Fishkill Creek was entering the sanitary sewer system along the pipe that crosses the Creek just upstream of Wolcott Avenue (see attached image).
Once the localized area of concern was identified, the City has communicated with several contractors to meet at the site today to determine how best to investigate the leak to identify the specific location and nature of the breach. Given that the pipe crossing the creek is submerged and surcharged with water, visual observations of the breach are complicated and may require the use of sonar equipment and/or pump-around to inspect the specific location of the breach. Once the specific location and nature of the breach has been determined, the City will then develop a plan of repair.
To mitigate this condition, the City has also requested proposals from contractors to bypass pump the flows around this creek crossing. This will eliminate the 3 million gallons per day of additional flow to the sanitary sewer system, and is necessary to conduct the investigation and repair the line. The City suspects the pipeline was damaged during Hurricane Irene because the additional flow was not observed prior to the storm, but has only been detected afterwards.
The City has also monitored the area around the crossing for any evidence of sewage flow into the Creek and none has been observed. Dye injected into the sewer line was not observed in the Creek. This, together with the heavy increase in flow from the Creek, leads the City to believe the water from the Creek is entering the pipe and is creating enough pressure to prevent sewage from escaping. The City is, however, monitoring this daily.
The City will continue to keep DEC and the Dutchess County Department of Health apprised of this situation. As this matter involves working in the Creek and is expected to be a significant financial burden, the City has requested State assistance with respect to funding and any necessary permits be expedited or otherwise not required due to this extreme emergency.
Beacon, New York