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Water and sediment testing

EPA is currently collecting and analyzing water and sediment samples to help states and other federal agencies understand the immediate and long-term impacts of oil contamination along the Gulf coast. The results and the interpretation of all data collected by EPA will be posted to

Water and sediment samples are being taken prior to oil reaching the area to determine water quality and sediment conditions that are typical of selected bays and beaches in Louisiana, Mississippi, Alabama, and the Florida panhandle. This data will be used to supplement existing data generated from previous water quality surveys conducted by states, EPA, and others.   

Water sampling will continue once the oil reaches the shore; periodic samples will be collected to document water quality changes. EPA will make data publicly available as quickly as possible. Other state and federal agencies make beach closure and seafood harvesting and consumption determinations, but the data generated by EPA will assist in their evaluations. 

Why is EPA sampling and monitoring the water?
EPA is tracking the prevalence of potentially harmful chemicals in the water as a result of this spill to determine the level of risk posed to fish and other wildlife. While these chemicals can impact ecosystems, drinking water supplies are not expected to be affected.

The oil itself can cause direct effects on fish and wildlife, for example when it coats the feathers of waterfowl and other types of birds. In addition, other chemical compounds can have detrimental effects. Monitoring information allows EPA to estimate the amount of these compounds that may reach ecological systems. When combined with available information on the toxicity of these compounds, EPA scientists can estimate the likely magnitude of effects on fish, wildlife, and human health.

To Learn More:

Coastal Water Sampling
Sediment sampling