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City of Oswego, NY Clean Water Act Settlement

(Washington, DC - May 13, 2010) To resolve long-standing problems with unpermitted sewer overflows, the city of Oswego, N.Y., will invest an estimated $87 million in improvements to its west side sewer system, the Justice Department and U.S. Environmental Protection Agency (EPA) announced today. The New York State Department of Environmental Conservation was also a partner in the agreement.

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Overview of Facility

The City of Oswego, which has a population of approximately 18,000, owns and operates a "publicly owned treatment works" ("POTW"), as defined at 40 C.F.R. § 403.3, part of which is located on the east side of the Oswego River ("East Side System"), and the remainder of which is located on the west side of the River ("West Side System"). The above-captioned action addresses violations in the West Side System only. The West Side System services approximately 10,000 people, including citizens of Oswego's west side and certain surrounding communities. The West Side System includes, without limitation, a wastewater treatment plant ("WWTP"), located at 7 West Schuyler Street, Oswego, New York 13126, and a wastewater collection and transmission system ("WCTS"), which conveys wastewater to the WWTP. The WCTS includes a component designed to collect and transmit a combination of sanitary sewage (including domestic, industrial and commercial wastewater) and storm water ("combined sewer system" or "CSS") and a component designed to collect and transmit sanitary sewage only ("separate sanitary system" or "SSS"). The West Side System receives wastewater from residential, commercial, and industrial sources located in and around that portion of the City located on the west side of the Oswego River (including the Oswego Harbor), near Lake Ontario.

At least during the period from approximately March 31, 2003 through the present day, the City discharged pollutants from point sources not authorized by the State Pollutant Discharge Elimination System ("SPDES") Permit or by any other permit issued by EPA or an authorized state pursuant to Section 402 of the CWA, 33 U.S.C. § 1342, including, without limitation, to the following:

  • Combined Sewage from an unauthorized location on the Oswego Riverwalk
  • Sanitary Sewage at a pre-WWTP bypass location

Based on estimates provided by the City of Owego, approximately 377,740 gallons of combined sewage has been discharged annually at an unauthorized CSO point and 8,470,000 gallons of sanitary sewage has been discharged annually.

Additionally, the City has not installed SPDES Permit-required disinfection facilities to treat the combined sewage discharged at its one authorized Combined Sewer Overflow ("CSO") point.

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  • Clean Water Act (CWA) Sections 311(b), 301(a)

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Injunctive Relief

Based on the proposed Consent Decree, the City of Owego will eliminate annually 10.7 MG of combined sewer overflows (CSO) and 8.5 MG of sanitary sewer overflows (SSO) by implementing a program, estimated by the City to cost $87 million, and includes the following:

  • Separate at least 75% of its combined sewer system;
  • Expand its current WWTP;
  • Perform ongoing flow monitoring at strategic system locations;
  • Implement seasonal disinfection;
  • Make improvements in the separate sewer system in order to remove excessive infiltration and inflow; and
  • Implement an approvable post-construction monitoring program.

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Pollutant Addressed

Based on an application of EPA's pollutant load reduction calculators, the following load reductions have been calculated on a lbs/year basis:

Parameter CSO SSO Total
TSS 43,024 13,205 56,229
BOD5 756 12,640 13,396
COD 23,818 31,635 55453
TN --- 2,051 2,051
TP --- 293 293

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Health and Environmental Effects

Combined sewer overflows, or CSOs, are remnants of the country's early infrastructure. In the past, communities built sewer systems to collect both storm water runoff and sanitary sewage in the same pipe. During dry weather, these "combined sewer systems" transport wastewater directly to the sewage treatment plant. In periods of rainfall or snowmelt, however, the wastewater volume in a combined sewer system can exceed the capacity of the sewer system or treatment plant. For this reason, combined sewer systems are designed to overflow occasionally and discharge excess wastewater directly to nearby streams, rivers, lakes, or estuaries. Combined sewer overflows (CSOs) contain not only storm water but also untreated human and industrial waste, toxic materials, and debris. This is a major water pollution concern for cities with combined sewer systems. CSOs are among the major sources responsible for beach closings, shellfishing restrictions, and other water body impairments.

CSOs and SSOs contain raw sewage that can carry bacteria, viruses, protozoa (parasitic organisms), helminths (intestinal worms), and borroughs (inhaled molds and fungi). The diseases they may cause range in severity from mild gastroenteritis (causing stomach cramps and diarrhea) to life-threatening ailments such as cholera, dysentery, infections hepatitis, and severe gastroenteritis.

People can be exposed through:

  • Sewage in drinking water sources.
  • Direct contact in areas of high public access such as basements, lawns or streets, or waters used for recreation. At least one study has estimated a direct relationship between gastrointestinal illness contracted while swimming and bacteria levels in the water.
  • Shellfish harvested from areas contaminated by raw sewage. One study indicates that an average of nearly 700 cases of illness per year were reported in the 1980s from eating shellfish contaminated by sewage and other sources. The number of unreported cases is estimated to be 20 times that.
  • Some cases of disease contracted through inhalation and skin absorption have also been documented.

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Civil Penalty

Oswego will pay a total penalty of $99,000 to resolve its alleged liability for CWA violations, half of which will be paid to the U.S. Treasury and the remaining half to the State of New York.

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For more information, contact:

Alan Morrissey
1200 Pennsylvania Avenue, NW (2243A)
Washington, DC 20460
(202) 564-4026

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