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 [Photo: USGS scientist collects water-quality samples.]

USGS scientists deploy SPMD and POCIS samplers to collect waterborne contaminants in Manoa Stream on Oahu, Hawaii.


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USGS Water-Quality Sampling of Flood Waters > 2012 - Hurricane Sandy

USGS Water-Quality Sampling after Hurricane Sandy, October 2012

Update September 2014:Using Science to Strengthen our Nation's Resilience to Tomorrow's Challenges—Understanding and Preparing for Coastal Impacts

Update July 2013:Meeting the Science Needs of the Nation in the Wake of Hurricane Sandy — A USGS Science Plan for Support of Restoration and Recovery

Originally posted October 31, 2012; updated November 7, 2012

Note: For the latest disaster and emergency response information for your area, please refer to FEMA or your local office of emergency services.

Please note: this page highlights USGS water-quality sampling related to Hurricane Sandy. For all USGS Hurricane Sandy flooding response activities, see the main USGS Hurricane Sandy page.


As hurricane Sandy approached and hit areas of the eastern coast, USGS field crews prepared response activities and were among the first responders. Storms and associated flooding can affect the quality of our Nation's water resources. USGS scientists, engineers, and technicians have been out collecting data during and after the storm to monitor the impact of Hurricane Sandy on coastal and inland areas.

Essential elements of the USGS response involves making storm-surge, streamflow, and water-quality measurements, and providing geospatial products of the hurricane's movement and aftermath. The results from this work will continue to be analyzed through the coming days and weeks to provide scientific assessments of how the chemical and biological quality of streams and other water bodies are affected.

High-water events on the scale of Hurricane Sandy can cause changes in water quality that affect human health and the environment or affect commercial and recreational use of our Nation’s water resources by:

  • flushing large quantities of nutrients, pesticides, and bacteria into rivers;
  • altering sediment flow; and (or)
  • exceeding concentration standards of E. coli in surface water used for drinking.

Excessive nutrients in rivers, streams, and coastal areas can cause algal blooms that increase the costs of drinking-water treatment, limit recreational activities, and threaten valuable commercial and recreational fisheries. Increased sediment can cause costly changes in shipping channels, where new sediment can require additional dredging.

The USGS responds to such major events by working with local, State, and Federal agencies and the citizenry to identify, quantify, and understand environmental and public issues and concerns. USGS collection and analysis of data during and after flooding events helps science, relief, and health agencies better understand the effects on water quality in the short and long term, and provide the data needed for future response and resource management.

Water-Quality Response to Large-Scale Flooding

In response to Hurricane Sandy, the national water-quality programs of the USGS are coordinating and conducting water-quality sampling as part of cooperative State-wide ambient monitoring programs and the Chesapeake Bay Program, Delaware River Basin Commission, and state and local hurricane response efforts. By coordinating water-quality sampling among different monitoring programs, the USGS is able to more efficiently obtain high-flow samples across river basins, and explore ways to maximize opportunities during extreme-flow events. The frequency and location of water sampling varies according to local conditions and depends on the needs and concerns of partnering agencies and local communities.

Streamflow conditions are being monitored across the area most affected by Hurricane Sandy to assess locations for collection of high-flow water-quality samples, while USGS scientists determine the chemical analyses to be performed on the samples collected. The data from water-quality sampling during such high-flow events are needed to calculate the loads of chemical, biological, and particulate substances – such as nitrogen, phosphorus, and sediment – that are being transported by floodwaters to downstream and sensitive receiving waters of the Chesapeake Bay, Delaware Bay, Narragansett Bay and Long Island Sound. Depending on the ground conditions observed by USGS technical field staff, samples also may be analyzed also for pesticides, petroleum products, E. coli and other fecal indicator bacteria, and (or) other contaminants.

USGS Stations with Realtime Water-Quality Data

The USGS has a growing realtime water-quality network funded in part by state and local cooperators. The realtime network now may be sufficiently extensive to document water-quality responses to hydrologic hazards. Data are transmitted to the public in realtime on NWISWeb from gages in rivers, streams, estuaries, and embayments.

The capability of this network to document the water-quality response to hydrologic hazards such as Hurricane Sandy is being evaluated for the first time. Realtime water-quality sensors can reduce the need to collect and ship water-quality samples to laboratories for analysis, thereby reducing the cost, as well as time lag, of responding to hydrologic hazards. The USGS is developing and testing quality-assurance measures to evaluate and support this work.

In States affected by Hurricane Sandy, the network features over 400 realtime water-quality gages that measure and report streamflow and air and water temperature. At many of these gages, realtime data are used to provide information on storm-related changes to water-quality parameters, including:

  • water salinity -- an indicator of the amount of dissolved substances
  • pH -- a measure of the levels of acidic or alkaline conditions
  • dissolved oxygen -- an indicator of hypoxia
  • nitrate -- a measure of plant nutrients
  • chlorophyll -- an indicator of algal productivity
  • turbidity -- an indicator of suspended sediments/li>

Sensors are in place at inland and coastal areas hardest hit by Hurricane Sandy (October 2012). The files below provide a list of USGS stations in affected coastal and inland areas for which realtime water-quality data are available online through NWISweb:

The temporally rich data sets from these realtime networks can be used for hydrologic and water-quality modeling and surveillance activities. For example, these data can be used to address water-quality issues related to fish and shellfish production and nutrient enrichment and hypoxia. Streamflow and salinity can be used to quantify the extent of freshwater delivery from rivers to coastal areas. Freshwater inputs are known to be important to shellfish propagation. Floods may shift this balance thereby affecting shellfish production. Nitrates delivered in large amounts by floods are known to contribute to nutrient enrichment, stimulate chlorophyll production, and result in dissolved oxygen demand leading to hypoxia in coastal waters and impaired fisheries. Additional sensors can be added to detect hydrocarbons in water.

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Water-Quality Information in Your Area

For local water-quality information or to learn more about USGS Hurricane Sandy response activities, you can also vist the web sites for USGS Water Science Centers in impacted states:

For more information:

USGS Flood Monitoring and Data Collection

For information on overall USGS flood monitoring and data collection activities, see:

For more information on USGS water-quality sampling, contact the USGS Office of Water Quality.

To learn more about USGS water-quality sampling methods and protocols, see:

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Flooding and Water-Quality Health and Safety Information

Every effort should be made to limit contact with flood water due to potentially elevated levels of contamination associated with raw sewage and other hazardous substances.

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Page Last Modified: Wednesday, 28-Dec-2016 18:54:57 EST