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Numerous federal and state regulations and programs are aimed at improving urban streams. These regulatory guidelines influence our watershed planning objectives.

The Clean Water Act of 1972 (CWA)

The passage of the Clean Water Act (CWA) created a framework for regulating discharges into the waters in the United States and establishing water quality standards for surface waters. Under the CWA, industries, municipalities, and other facilities were forced to implement pollution control programs.

The objective of the CWA is to restore and maintain the chemical, physical, and biological integrity of the nation's waters by preventing point and nonpoint pollution sources, providing assistance to publicly owned treatment works for the improvement of wastewater treatment, and maintaining the integrity of wetlands.

Regulating discharges that go directly into surface waters (point sources) became critical to improving surface water quality and the surrounding environment. The CWA enacted a permit program, the National Pollutant Discharge Elimination System (NPDES), to manage and control these discharges.

Combined Sewer Overflow (CSO) Control Policy

This policy published in April 19, 1994 establishes a national approach for control of CSOs through the NPDES permit program. This policy provides guidance on coordinating the planning, selection, and implementation of CSO controls to meet the requirements of the Clean Water Act as flexibly and cost-effectively as possible and to allow for public involvement during the decision-making process.

One of the first requirements of CSO permittees was the implementation of nine minimum technology-based controls no later than January 1, 1997. The Nine Minimum Controls are measures that can reduce the prevalence and impacts of CSOs and are not expected to require significant engineering studies or major construction.

Communities with combined sewer systems are also expected to develop long-term CSO control plans that will ultimately provide for full compliance with the Clean Water Act, including attainment of water quality standards. The long-term CSO control plans should consider the site-specific nature of CSOs and evaluate the cost effectiveness of a range of control options/strategies.

The Clean Water Act, Section 303 Total Maximum Daily Load (TMDL) Process

Under section 303(d) of the Clean Water Act, states, territories, and authorized tribes are required to develop lists of impaired waters. These are waters that are too polluted or otherwise degraded to meet the water quality standards set by states, territories, or authorized tribes. The law requires that these jurisdictions establish priority rankings for waters on the lists and develop TMDLs for these waters. A TMDL is a calculation of the maximum amount of a pollutant that a waterbody can receive and still safely meet water quality standards.

TMDL regulations seek to improve water quality on impaired streams and water bodies. This involves collecting data on point and nonpoint source pollution loads and using the data to set maximum allowable loads from each source. The goal of the program is to strengthen each state's ability to meet clean water goals, to provide a list of all polluted waters, and to encourage cost-effective clean-up by guaranteeing that all sources of pollution are taken into account in the clean-up plans.

NPDES Municipal Separate Storm Sewer Systems (MS4) Stormwater Regulations

This regulation seeks to prevent harmful pollutants from being washed or dumped into a MS4 and therefore discharged directly into surface waters without treatment. This regulation required operators of MS4s to obtain a NPDES permit and develop a stormwater management program (SWMP). The SWMP must include measurable goals and implement stormwater management control (BMPs). Due to the large number of operating MS4s, this regulation was passed in two phases:

PA Act 167 Stormwater Management Planning

Act 167, the Stormwater Management Act of 1978, requires each county in Pennsylvania to prepare and adopt a stormwater management plan for each designated watershed in the county. A Stormwater Management Plan provides a mechanism for municipalities within the watershed to plan for and manage increased runoff associated with possible future development and land use change. It is not the intent of this plan to solve existing flooding or runoff problems (although this is becoming more of an expectation through Act 167 products such as detention discharge rates related to basin location), but to identify them for future correction and assure that problems do not get worse.

The Safe Drinking Water Act of 1974

This is the principal law created to ensure safe drinking water for the public by establishing standards for water quality. State laws, like the Clean Streams Law, expand on the federal laws by addressing regional issues.

Long Term 2 Enhanced Surface Water Treatment Rule (LT2 Rule)

The Environmental Protection Agency has developed LT2 to improve your drinking water quality and provide additional protection from disease-causing microorganisms and contaminants that can form during drinking water treatment.