The previous page described the relationship between uses and standards for the waters of the Commonwealth. The Integrated Water Quality Report issued by the PA Department of Environmental Protection every two years presents the current status of lakes, rivers, and streams in meeting the standards for the designated use of each. The report includes a narrative discussion of Pennsylvania's efforts to meet the obligations under sections 305(b) and 303(d) of the Clean Water Act of 1972. Also presented is a discussion of the methods used to collect data for assessing the waters. But the 'meat-and-potatoes' of the report are the lists for each of the categories described below.
Category 1: Waters attaining all designated uses.
Category 2: Waters where some, but not all, designated uses are met. Attainment status of the
remaining designated uses is unknown because data are insufficient to categorize the water.
Category 3: Waters for which there are insufficient or no data and information to determine if
designated uses are met.
Category 4: Waters impaired for one or more designated uses but not needing a total maximum
daily load (TMDL). These waters are placed in one of the following three subcategories:
• Category 4A: TMDL has been completed.
• Category 4B: Expected to meet all designated uses within a reasonable timeframe.
• Category 4C: Not impaired by a pollutant and not requiring a TMDL.
Category 5: Waters impaired for one or more designated uses by any pollutant. Category 5
includes waters shown to be impaired as the result of biological assessments used to evaluate
aquatic life use. Category 5 constitutes the Section 303(d) list EPA will approve or disapprove
under the Clean Water Act.
Section 303(d) of the act requires states to list all impaired waters not supporting uses even after appropriate and required water pollution control technologies have been applied. For example, a waterbody impacted by a point source discharge that is not complying with its effluent limits would not be listed on the 303(d) list. The department would correct the water impairment by taking a compliance action against the discharger. If the waterbody still did not meet water quality standards after achieving compliance with its permit requirements, it would be included on the 303(d) list of impaired waters. The 303(d) list includes the reason for impairment, which may be one or more point sources (like industrial or sewage discharges), or non-point sources (like abandoned mine lands or agricultural runoff).
States or the U.S. Environmental Protection Agency (EPA) must determine the conditions that would return the water to a condition that meets water quality standards. As a follow-up to listing, the state or EPA must develop a Total Maximum Daily Load (TMDL) for each waterbody on the list. A TMDL identifies allowable pollutant loads to a waterbody from both point and non-point sources that will prevent a violation of water quality standards. A TMDL also includes a margin of safety to ensure protection of the water.
A TMDL is designed to reduce pollutant loads to impaired waters and enable these waters to meet water quality standards. Pennsylvania has committed to developing TMDLs for all impaired waterbodies and will use both traditional and new approaches to correct water quality problems. Public participation is an important part of TMDL development. DEP publishes notice of the availability of each TMDL and provides a comment period as well as a public meeting. All comments are considered before the TMDL is submitted for EPA’s approval.
Waterbody assessment and data evaluation is a continuous process. The 2010 Integrated Report was developed using information from stream and lake surveys and other sources, including DEP’s Statewide Surface Water Assessment Program, the Non-point Source Program, and when available existing and readily available data submitted by external groups and agencies.