DEP smoke testing release, Brooklyn sewers, Aug 1984

NYC 9/11 Public Portal Document

FACT SHEET BACKGROUND

Under Public Law 9.2-50Q and the Federal Water Polution Control Act Amendments of 1974, the U.S. Environmental Protection Agency (EPA) requires that after July 1, ±973 all applicants for treatment works grants must demonstrate that an existing sewer system discharging into treatment works is not subject to excessive Infiltration/Intlow. A three step program to satisfy the requirements of this public law consists of an Infiltration/Inflow (I/I) Analysis, a Sewer System Evaluation Survey and a Sewer Rehabilitation Program. The City of New York, Department of Environmental Protection initiated the upgrading/expansion of the Coney Island Treatment Plant in the late 1970‘s. For the improvement program costs to be eligible for federal finding, the City performed the first step in I/I Process. The Bureau of Sewers completed an I/I Study in March 1979 which demonstrated that various areas within the Coney Island service area contribute potentially excessive I/I. This report recommended that a Phase II Sewer System Evaluation Survey (SSES) be performed to locate those sources that are contributing excess flow. Once the location of the sources are found and the quantity of excess flow determined, a cost-effectiveness analysis is performed to see if It is appropriate to rehabilitate these sources or to treat the excess flow. Smoke testing is a procedure employed as part of the SSES to locate sources.

PURPOSE FOR SMOKE TESTING

The City of New York, Department of Environmental Protection tNYC DEP), Bureau of Water Pollution Control is presently conducting a study to determine the condit on of existing sewers which convey sewage to the Coney Island Treatment Plant. As part of the study, a program known as "Smoke Testing" will be employed to locate sources which are contributing additional rainfall-related flows (inflow) to the sanitary sewers.

Smoke testing is a common procedure employed by municipalities to identity sources of inflow. The method is used to detect inflow sources such as roof leaders, cellar, yard, area, and foundation drains, abandoned building sewers, and storm sewer cross connections. Smoke testing is also used to detect structural damages and leaking joints in sewer pipes and manholes. While this is the first time that this program is to be performed in New York City, it is anticipated that other Q areas of the City will be smoke tested when the sewer system . , in those sections are to be evaluated. Smoke testing of the > • . * 0

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