&EPA www.epa.gov/research -x ch| BU - * science in ACTION ILDING A SCIENTIFIC FOUNDATION FOR SOUND ENVIRONMENTAL DECISIONS T— WATER QUALITY RESEARCH PROGRAM RESEARCHERS STUDY "DEAD ZONES" IN U.S. WATERS TO ALLEVIATE HARMFUL EFFECTS Issue Hypoxia, a condition of low oxygen levels in water, threatens coastal waters and estuaries worldwide by creating "dead zones" where aquatic life cannot live. Dead zones can lead to fish kills, cause toxicity in shellfish, and damage ecosystems and wildlife. There are economic consequences to hypoxia as well. Impacted waters can result in communities spending more to treat their drinking water. They can also threaten commercial fisheries and make beaches unattractive for swimming. Hypoxia events have increased rapidly in the United States over the past several decades. The United States has some of the largest dead zones in the world, notably in the Gulf of Mexico, Chesapeake Bay and Oregon coast. Human activities are often the cause of hypoxia in coastal waters. Major contributors are increased runoff of nutrients used in agriculture, stormwater that carries untreated wastewater resulting from treatment plant overflows, and air pollution. Hypoxia is a scientifically complex coastal issue that is being investigated by U.S. Environmental Protection Agency scientists so that water resources and aquatic life can be protected. Scientific Objective EPA's Office of Research and Development (ORD) conducts research as part of a broad federal effort to reduce and control hypoxia and its effects. EPA researchers are supporting the Agency's work to develop nutrient criteria needed to control high levels of nitrogen and phosphorous runoff in the water that can lead to hypoxia. Efforts are also underway to improve the ability to assess and predict hypoxia events and their impacts. Research includes: • Modeling of pollutants that are transferred from the air to the water's surface to determine forecasts of deposition changes • Conducting case studies like one in Yaquina Bay, Oregon, to provide approaches for nutrient criteria development and aquatic life protection • Investigating nutrients released from wastewater treatment plants to understand how they contribute to hypoxia • Improving manure- management practices to reduce impacts of manure runoff earth nmd on back ¦ U.S. Environmental Protection Agency I Office of Research and Development ------- *>EPA C WATER QUALITY RESEARCH PROGRAM www.epa.gov/research 1 • Surveying coastal shelves and oceanographic conditions and processes • Evaluating best management practices to restore watersheds A large part of EPA's hypoxia research focuses on the northern Gulf of Mexico, the site of the second largest dead zone in the world. This hypoxic zone forms every summer due to excess nutrients flowing from the Mississippi River. EPA research seeks to reduce the zone's size and improve water quality by conducting surveys, doing computer modeling and developing scientific information in databases. Application and Impact EPA's hypoxia research provides a scientific foundation for nutrient criteria and standards development to control hypoxic events in U.S. waters and mitigate their ecological consequences. As part of the Interagency Working Group on Harmful Algal Blooms, Hypoxia and Human Health, a 2010 report to Congress assesses the hypoxia issue. The report, Scientific Assessment of Hypoxia in U.S. Coastal Waters, details the progress made by federal hypoxia research, including: • Improved quantification of hypoxia • Improved characterization of hypoxia impacts • Quantified nutrient flux (flow) to coastal waters • Approaches for reducing nutrient inputs to coastal waters Scientists from NOAA, EPA, USGS, USD A and the Virginia Institute of Marine Science co- authored the report. Additional contributions from EPA's hypoxia research include: • The 2002 National Water Quality Inventory, submitted to Congress by the Office of Water, which reports 17 percent of estuarine waters assessed were affected by hypoxia due to increased nutrient concentrations from human activities. • The ReNuMA watershed model developed by scientists funded by EPA and the National Oceanic and Atmospheric Administration, which enables the examination of various scenarios for reducing nitrogen losses from the landscape. REFERENCES Scientific Assessment of Hypoxia in U.S. Coastal Waters. Interagency Working Group on Harmful Algal Blooms, http://www.wliitehouse.gov/administration/eoD/ost p/nstc/oceans Final Report: Developing Regional-scale Stressor Models for Managing Eutrophication in Coastal Marine Ecosystems, Including Interactions of Nutrients, Sediments, Land-use Change, and Climate Variability and Change. http ://cfpub. epa. gov/ncer ab stracts/index, cfm/fiise action/displav.abstractDetail/abstract/6138/report/F National Water Quality Inventory: Report to Congress, 2002 Reporting Cycle httv://www.eva.9ov/}Q5b/2002revort' ReNuk LA Watershed model httv://www. eeb. comell. edu hio^/eo none usda renu ma. htm CONTACT Rick Greene, EPA's National Health & Environmental Effects Research Laboratory, 850- 934-2497 or greene.rick@epa.gov Jim Hagy, EPA's National Health & Environmental Effects Research Laboratory 850- 934-2455 or hagv.iim@epa.gov SEPTEMBER 2010 U.S. Environmental Protection Agency Office of Research and Development ------- |