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Special Protection Waters (SPW) Program
Program History

In 1992, DRBC adopted SPW regulations for point source (or "end-of-pipe") discharges, which were amended in 1994 to also include non-point source pollutant loadings carried by runoff. The regulations were enacted to protect existing high water quality in areas of the Delaware River Basin deemed "to have exceptionally high scenic, recreational, ecological and/or water supply values." They initially applied to a 121-mile stretch of the Delaware River from Hancock, N.Y. downstream to the Delaware Water Gap, and its drainage area. This includes the upper and middle sections of the non-tidal river federally designated as "Wild and Scenic" in 1978, as well as an eight-mile reach between Milrift and Milford, Pa., which is not federally designated.

Map of 1992 SPW-classified area (pdf 313 KB)

In 2000, federal legislation was enacted adding key segments of the Lower Delaware and selected tributaries to the National Wild and Scenic Rivers System. This designation was followed in April 2001 with a petition from the Delaware Riverkeeper Network to classify the Lower Delaware, the 76-mile stretch of the non-tidal river between the Delaware Water Gap National Recreation Area and the head of tide at Trenton, N.J., as SPW. Extensive data were collected from 2000 through 2004 which confirmed that existing water quality in this stretch of river exceeded most state and federal standards.

Data collected from 2000 through 2004 and associated eligibility reports

Based in part upon these findings, the DRBC in 2005 temporarily classified the Lower Delaware as SPW. This temporary designation made the Lower Delaware subject to all SPW regulations except those that required the use of numeric values for existing water quality. Temporary designation provided a measure of protection while allowing time for the public rulemaking process to take place and for implementation details to be thoroughly considered.

The commission extended the temporary designation on four different occasions:

On July 16, 2008, by unanimous vote, the DRBC permanently designated the Lower Delaware as Significant Resource Waters, one of the two available SPW classifications. The entire 197-mile non-tidal Delaware River is now protected by SPW anti-degradation regulations.

Brief Description of SPW Regulations

Overview map of SPW Drainage Area.


Within the drainage area to Special Protection Waters, DRBC approval is required for new and expanding industrial and municipal wastewater treatment plants when the proposed facility is designed to discharge a daily average rate of 10,000 gallons a day or more. In the rest of the basin, the review threshold remains 50,000 gallons a day or more.

The regulations discourage new and increased discharges of wastewater directly to the designated waterways by prohibiting new wastewater treatment facilities and substantial alterations and additions to existing facilities discharging directly to Special Protection Waters unless all non-discharge/load reduction alternatives have been fully evaluated and rejected because of technical and/or financial infeasibility.

In addition, new discharges and substantial alterations and additions to existing discharges are prohibited within the drainage area to waters classified as SPW unless natural treatment alternatives for all or a portion of the discharge have been evaluated and rejected because of technical and/or financial infeasibility. Non-discharge alternatives and natural treatment alternatives include land applications like spray irrigation where treated wastewater is applied to the ground.

To obtain DRBC approval, new discharges and substantial alterations and additions to existing discharges within the drainage area to waters classified as SPW must demonstrate no measurable change to existing water quality as defined by the regulations for a list of seven or eight parameters (depending on the location of the discharge) at established water quality control points.

The SPW regulations further require that the minimal level of wastewater treatment for all new discharges and substantial additions or alterations to existing discharges directly to Special Protection Waters will be “Best Demonstrable Technology.” Best Demonstrable Technology (BDT) is defined for municipal facilities by 30-day average effluent criteria for seven parameters plus ultraviolet light disinfection. Equivalent criteria for industrial facilities are identified on a case-by-case basis.

Projects located in the drainage area of Special Protection Waters that are subject to DRBC review must also have a Non-Point Source Pollution Control Plan (NPSPCP) that has been approved by the commission. The NPSPCP describes the Best Management Practices that will be used at the project site and service area to control the increases in non-point source pollutant loadings resulting from the project.

Monitoring is undertaken by the commission and the National Park Service (NPS) in order to assess compliance with water quality criteria and to allow revised definitions of existing water quality (EWQ) and/or determine that EWQ is currently being maintained in Special Protection Waters. Segments monitored in the DRBC-NPS partnership include the Upper Delaware Scenic and Recreational River (UPDE), Delaware Water Gap National Recreation Area (DEWA), and the Lower Delaware Scenic and Recreational River (LDEL). NPS staff lead the monitoring programs in UPDE and DEWA, while commission staff are in charge of the LDEL program. Throughout the 200-mile non-tidal river, close to 60 sites are sampled between May and September and analyzed for nutrients, dissolved oxygen and other conventional pollutants, solids, bacteria, macroinvertebrates, periphyton (alga), and flow.

DRBC/NPS Scenic Rivers Monitoring Program and Lower Delaware Monitoring Program

DRBC and the National Park Service (NPS) partner in this effort to monitor and manage the water quality in the Special Protection Waters and National Wild and Scenic River segments of the Upper Delaware Scenic and Recreational River (UPDE), Delaware Water Gap National Recreation Area (DEWA), and the Lower Delaware Scenic and Recreational River (LDEL). NPS staff lead the monitoring programs in UPDE and DEWA, while commission staff are in charge of the LDEL program.

The goals are to assess compliance with water quality criteria and to allow revised definitions of existing water quality (EWQ) and/or determine that EWQ is currently being maintained in Special Protection Waters.

Throughout the 200-mile non-tidal river, close to 60 sites are sampled between May and September and analyzed for nutrients, dissolved oxygen and other conventional pollutants, solids, bacteria, macroinvertebrates, periphyton (alga), and flow.