Read the 2022 TREB

February 9th, 2023 News

PDE Releases 2022 Technical Report for the Delaware Estuary and Basin

Estuary and Basin maintains a “fair” health grade from 2017


The Partnership for the Delaware Estuary (PDE) recently unveiled its 2022 Technical Report for the Delaware Estuary and Basin (TREB). The report, which has been published every five years since 2012, is the culmination of two years of collaboration among environmental scientists in Delaware, New Jersey, and Pennsylvania. PDE staff, members of the Delaware River Basin Commission, and others, presented a snapshot of the TREB at the bi-annual Delaware Estuary Science & Environmental Summit, held in Atlantic City.

Overall, there’s both good and bad news. The TREB concludes that the Delaware Estuary and Basin maintains its “fair” health rating. Sturgeon numbers are on the rise and nutrient loads have improved since the 1960s, but numbers of striped bass continue to decline and sea level rise is showing no sign of slowing down.

“The TREB helps us think about the health of the ecosystem as a whole rather than specific facets, and it shows that while we have made great progress we have more work to do to address legacy issues, emerging threats, and adapt to climate change,” said Danielle Kreeger, PDE’s Senior Science Director.

The TREB provides an overview of the status and trends of more than 50 environmental indicators, including a diverse suite of water, habitat, and living resources. It’s also a technical snapshot of the primary indicators of the Delaware River Watershed’s general health.

Some parameters, such as dissolved oxygen concentration and sturgeon abundance, are improving thanks to proactive management. For example, more than 90 percent of tested areas met dissolved oxygen criteria. On the other hand, some indicators such as impervious cover, winter streamflow, sea level rise, and striped bass abundance are of increasing concern.  For example, increasing impervious surface in the Delaware Estuary and Basin increases storm water runoff, flooding and can impair water quality.

“We are very grateful for all of the partners who contributed to the 2022 TREB including the members of the Delaware Estuary Program’s Science and Technical Advisory Committee,” said Kathy Klein, Executive Director of the Partnership for the Delaware Estuary. “The 440-page report is an important tool that helps to assess the overall environmental condition of the watershed. The indicators help raise awareness about important environmental issues, serve as tools for evaluating the effectiveness of management actions, and can function as early warning signals for detecting adverse changes in environmental quality.”

The Delaware Estuary Watershed and Basin contains a network of rivers, streams, and communities across 42 counties in four states, covering 13,539 square miles. These places are home to more than 13 million people who draw 6 billion gallons of water daily, not to mention thousands of birds, fish, and plants.

Namsoo Suk, Ph.D., DRBC’s Director of Science and Water Quality Management noted, “Our mission of managing, protecting and improving the water resources of the Delaware River Basin presents a natural partnership opportunity with the Delaware Estuary Program. Evaluation results for more than 50 environmental indicators in the 2022 TREB report better equip our agency to protect aquatic resources, human health, and communities. DRBC values PDE’s cooperative approach to connect technical expertise from our agency and other partners and make the TREB report a true partnership product.”

Later this year, PDE will release a State of the Estuary report. This non-technical summary uses TREB information to provide the public with insight into the status and trends of select natural resources in the Delaware Estuary.

The 2022 Technical Report for the Delaware Estuary & Basin Report can be found on PDE’s website at

Additional questions can be directed to the Estuary Science Manager LeeAnn Haaf, Ph.D., at