Delaware • New Jersey • Pennsylvania
New York • United States of America
- Aquatic Life Designated Use Project
- Bacteria Monitoring
- Biomonitoring Program
- Chlorides Monitoring
- Contaminants of Emerging Concern
- Delaware Estuary Water Quality Monitoring Program
- Dissolved Oxygen and Nutrients
- Modeling
- Other Monitoring (e.g., Toxicity, Microplastics, Phytoplankton)
- PCBs and PMPs
- Special Protection Waters (SPW)
- Water Resource Data Sets
- Toxicity Studies & Fish Tissue Monitoring
- Microplastics, Metals & Sediment
- Phytoplankton
- Flow & Habitat Studies
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SPATT bags about to be deployed in the Delaware River. Photo by the DRBC. |
Ambient Toxicity Monitoring
As part of ongoing programs to control toxic substances in the Delaware Estuary, the DRBC conducts periodic monitoring of ambient water toxicity in the estuary and has requested monitoring of acute and chronic effluent toxicity by dischargers.
• Learn more about Ambient Toxicity Monitoring
Cyanotoxin Study
The DRBC is using the SPATT (Solid Phase Adsorption Toxins Tracking) methodology to track the presence or absence of cyanotoxins in the Delaware River. As drinking water intakes are situated along the Delaware River, it is important to understand if, and where, algal toxins are detected from a human health standpoint.
• Learn more about DRBC's Cyanotoxin Study
Fish Tissue Monitoring
Since 1990, DRBC has periodically sampled tissues of resident fish species in the non-tidal and tidal portions of the main stem Delaware River.
Data collected by DRBC help inform Fish Consumption Advisories issued by certain Basin states.
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DRBC staff takes a flow measurement in the Neshaminy Creek, one of the microplastics study sites. Photo by DRBC. |
Microplastics
DRBC received a grant to study microplastics in the Delaware River Estuary in 2018. Samples were collected in 2019, 2020 and 2021, with cleanups held at two hot spots in the fall of 2021. A final report was published in August 2022.
• Learn more about Microplastics & view the Study's Final Report
Monitoring for Metals
DRBC monitors metals, such as copper, aluminum, zinc, nickel, and mercury, in ambient water, sediment, and tissues of aquatic life of the Delaware Estuary to ensure compliance with water quality criteria.
• Learn more about Metals Monitoring
Sediment Sampling
DRBC samples sediment to monitor for PCBs, as well as for chlorinated pesticides, PFAS, metals and dioxin/furans.
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DRBC staff retrieves the fluorometer at Bristol, Pa. after deployment. Photo by the DRBC. |
Phytoplankton Study
DRBC's eutrophication model suggests that observed phytoplankton blooms in Zones 3-5 may be caused by transient micro-blooms in Zone 2 that propagate and magnify downstream in the estuary. Monitoring is needed to obtain additional field data to help explain observed phytoplankton blooms on finer geographic and temporal scales than existing monitoring regimes provide.
2024 Study
• Deployed continuous fluorometers at at three locations: Schuylkill River at Fairmount Dam; Delaware River at Bristol Wharf; and Delaware River at Chester (Kimberly-Clark gage), April - October
• Loggers deployed from April - October; staff collected surface water samples during deployment, weekly or bi-weekly
• Chlorophyll-a and algal samples were collected to identify density and composition
• All analytical work conducted by the Academy of Natural Sciences Drexel University
• Most phytoplankton activity at the Schuylkill River site
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Low flows in the Delaware River at Prallsville Mills. Photo by the DRBC. |
As needed, the DRBC performs various monitoring studies before, during and after low or high flow conditions (droughts, floods) to better understand impacts to habitat. Staff is also interested in how warmer air temperatures affect water temperatures.
In addition to sample collection and basic chemistry monitoring, staff can deploy HOBO meters to collect continuous data and take photography/video using a small, unmanned aircraft system (sUAS, i.e., a drone).
Thermal Imaging to Identify Heat Dissipation
Using a drone equipped with a thermal imaging camera, DRBC staff will perform thermal plume surveillance in the upper Delaware River.
This monitoring would target areas in the upper Delaware that support cold water fisheries. This data will help assess the accuracy of near-field modeling of heat dissipation areas and allow us to visualize and identify undocumented thermal plumes. Understanding if undocumented thermal plumes are occurring is important, as warmer waters impact cold water fish species.
Upper Delaware Low Flow Habitat Study
In support modeling efforts to better understand how low flows affect habitat, during times of low flow, staff will measure flow and depth at various locations in the upper Delaware River.
Copyright © Delaware River Basin Commission,
P.O. Box 7360, West Trenton, NJ 08628-0360
Phone (609)883-9500; Fax (609)883-9522
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