Back in April, PennFuture and our partners filed a petition to the U.S. Environmental Protection Agency (EPA), requesting a new water quality standard for dissolved oxygen for the urban stretch of the Delaware River. On December 1, the EPA took the rare step and granted our petition! 

While it might sound like a technical issue, this is a major development for our continued efforts to upgrade and protect the Delaware River estuary—the 38-mile stretch of the river from Trenton to the top of the Delaware Bay. 

The petition raised critical questions surrounding what defines “existing use” of this stretch of the river and how data-driven evidence demonstrates that existing use.  The problem here is that there is solid evidence that fish propagation is occurring in this section of the river. This evidence of an “existing use” formed the basis for our petition to EPA to upgrade the designated use to include propagation of fish.

As we explain below, PennFuture and our partners had petitioned the Delaware River Basin Commission (DRBC) years ago to recognize the propagation of fish and set appropriate standards to protect it. However, DRBC, the intergovernmental agency responsible for water quality protections in the Delaware River watershed, has failed to act on our petition in a timely manner. And so the time had come for us to petition EPA to step in and take control to protect the river under their overarching authority under the federal Clean Water Act.

The law. The federal Clean Water Act requires that regulators determine the “existing use” of a waterbody and establish a “designated use” that matches or goes beyond the existing use. At the moment, the designated use—with regard to aquatic life—is defined as “maintenance of resident fish and other aquatic life” and “passage for migratory fish.”  The currently applicable standards, in these zones of the River, do not include protections to provide for the “propagation of fish.” 

The science. Based on the “maintenance” designated use, the DRBC set a dissolved oxygen standard of 3.5 mg/L. Dissolved oxygen is required to support aquatic life. Yet pollution from industry, insufficiently treated sewage from wastewater plants, and the pollution carried to the river from our streets during rain events can have dramatic impacts on the ecosystem. High levels of pollution adversely affect aquatic habitats, potentially causing harmful algal blooms, which deprive the river of oxygen and create dead zones for other life. And the more sensitive juvenile fish populations that are present in areas where propagation of fish occur need a higher level of dissolved oxygen than those areas where only maintenance of adult populations is needed. Upgrading the designated use of this section of the river should result in the creation of higher dissolved oxygen standards necessary to protect all live stages of fish.

The evidence. Federally-protected Atlantic Sturgeon can be found in this stretch of the river—living and spawning, not just migrating through—and therefore need a higher dissolved oxygen standard in order to survive. The argument is simple. The fish are existing there, and this “existing use” by the sturgeon needs to be recognized by law.

This issue has been brewing for years. In 2013, Delaware Riverkeeper Network (DRN) and other organizations submitted an initial petition to the DRBC, urging it to recognize the emerging data that fish are now spawning in all zones of the Delaware Estuary. In 2021, DRN, PennFuture and others filed a supplemental petition with the DRBC, pointing to additional evidence of fish propagation and urging DRBC to move faster.  

PennFuture and our partners remain frustrated with the DRBC’s delay and inaction. PennFuture, DRN, and others filed a petition to the EPA in April, requesting: 

• EPA issue a rule that revises the designated uses for these urban zones to include a) maintenance and propagation of resident fish and other aquatic life, and b) spawning and nursery habitat for anadromous fish
• EPA upgrade the dissolved oxygen standard from 3.5 mg/L to 6/3 mg/L

On December 1, EPA granted the petition for rulemaking and set out a 12-month timeline for establishing new water quality standards for dissolved oxygen in this part of the Delaware. In making this determination, EPA found that “‘propagation of fish’” is “attainable” and that the “currently applicable dissolved oxygen criterion for these zones is not sufficient to protect propagation.” EPA determined, in other words, that the dissolved oxygen standard needs to be higher.  

Still to be determined is exactly what that higher standard will be. EPA expects to release draft regulations by 2024, which will be addressed in the years thereafter by the DRBC and the Pennsylvania Department of Environmental Protection (DEP), as well as the environmental agencies of New Jersey and Delaware. The higher water quality standards will then be implemented by upgrading wastewater treatment plants along the estuary as well as by creating more stringent permits for polluters along the river. Fortunately, significant increases in state and federal infrastructure funding could, in part, be used for these wastewater treatment plant upgrades.

PennFuture is committed to ensure the Delaware River’s new standards will protect the survival of the sturgeon as well as the health of other aquatic life in the basin.  Millions of residents use the Delaware River for recreation, food, and work. Our goal is to make sure that they will be able to do so for years to come.

Photo courtesy James Loesch/Flickr