National Estuarine Eutrophication 

Assessment Update

effects of nutrient 

enrichment in the 

nation’s estuaries: 

A Decade of Change
More information or access to data, products, and services can be obtained from:

National Estuarine Eutrophication Assessment

www.ian.umces.edu/neea/; http://www.eutro.us/; http://www.eutro.org/

University of Maryland Center for Environmental Science

http://ian.umces.edu/

NOAA’s National Centers for Coastal Ocean Science

http://coastalscience.noaa.gov/

NOAA’S Center for Coastal Monitoring and Assessment

http://ccma.nos.noaa.gov/

To receive copies of the report, contact:

Suzanne Bricker

Center for Coastal Monitoring and Assessment

National Centers for Coastal Ocean Science

N/NCCOS/CCMA SSMC4 Floor 9

1305 East West Highway

Silver Spring, MD 20910

suzanne.bricker@noaa.gov 

For bibliographic purposes this book may be cited as:

Bricker, S., B. Longstaff, W. Dennison, A. Jones, K. Boicourt, C. Wicks, and J. Woerner. 2007. Effects of Nutrient 

Enrichment In the Nation’s Estuaries: A Decade of Change. NOAA Coastal Ocean Program Decision Analysis 

Series No. 26. National Centers for Coastal Ocean Science, Silver Spring, MD. 328 pp.

Copyright © 2007 by the National Oceanic and Atmospheric Administration

First published 2007

Front cover photo: Ben Longstaff. Inset photos (top to bottom): Ben Longstaff, Adrian Jones, Tim Carruthers, 

Peter Doering, Jane Thomas
Effects of Nutrient Enrichment 

In The Nation’s Estuaries: 

A Decade of Change

Assessing change in eutrophic condition 

from the early 1990s to 2004

National Estuarine Eutrophication Assessment Update

effects of nutrient 

enrichment in the nation’s

estuaries: a decade of change

National Estuarine Eutrophication Update 

Authors:

Suzanne Bricker1, Ben Longstaff 2,William Dennison3, Adrian Jones3, Kate Boicourt2, Caroline Wicks2, and Joanna Woerner3

1 NOAA, National Ocean Service, National Centers for Coastal Ocean Science, Silver Spring, MD 

2 EcoCheck, NOAA Chesapeake Bay Office & University of Maryland Center for Environmental Science, Cooperative Oxford Laboratory, Oxford, MD

3 University of Maryland Center for Environmental Science, Cambridge, MD

Case study and chapter authors:

Rex Baumberger, Harbor Branch Oceanographic Institution

Brad Bedford, Harbor Branch Oceanographic Institution 

Robert W. Buddemeier, Kansas Geological Survey

Stefano Ciavatta, University of Venice (Italy)

Michael Connor, San Francisco Estuary Institute

William Dennison, University of Maryland Center for Environmental Science

Susan Dunham, National Oceanic and Atmospheric Administration

Ken Dunton, University of Texas at Austin

Joao Ferreira, Institute of Marine Research (Portugal)

Diane M. Gould, U.S. Environmental Protection Agency

Holly Greening, Tampa Bay Estuary Program

Matthew Hall, Maryland Department of Natural Resources

Brian Lapointe, Harbor Branch Oceanographic Institution

Ben Longstaff, NOAA/University of Maryland Center for Environmental Science

Douglas Lipton, University of Maryland College Park

Bruce Maxwell, Swarthmore College

Jan Newton, University of Washington 

Chris Onuf, U.S. Geological Survey

Roberto Pastres, University of Venice (Italy)

Nancy Rabalais, Louisiana Universities Marine Consortium

William Romano, Maryland Department of Natural Resources

Teresa Simas, Institute of Marine Research (Portugal)

Stephen V. Smith, Centro de Investigación Científica y de Educación 

Superior de Ensenada, (CICESE)

Paul Stacey, Connecticut Department of Environmental Protection

Brian Sturgis, National Park Service

Dennis Swaney, Cornell University

Peter Tango, Maryland Department of Natural Resources

David Taylor, Massachusetts Water Resource Authority

Mirta Teichberg, Boston University Marine Program

Mark Trice, Maryland Department of Natural Resources

Ivan Valiela, Boston University Marine Program

Peter Verity, Skidaway Institute of Oceanography

Baodong Wang, First Institute of Oceanography (China)

Rob Warner, National Oceanic and Atmospheric Administration

Catherine Wazniak, Maryland Department of Natural Resources

Xiao Yongjin, University of Algarve (Portugal)

Xuelei Zhang, First Institute of Oceanography (China)

Mingyuan Zhu, First Institute of Oceanography (China)
foreword 

In 1999, the National Estuarine Eutrophication Assessment described the scale, scope, and 

characteristics of nutrient enrichment and eutrophic conditions in the Nation’s estuaries. At the time, 

it was the most comprehensive examination ever reported of nutrient-related water quality impacts, 

their causes, and expected changes in condition in U.S. coastal water bodies. The results showed that 

most estuarine systems exhibited some level of eutrophication impact in the early 1990s. One of the 

main aims of the report was to develop a national strategy to limit the nutrient enrichment problems 

affecting U.S. estuarine and coastal water bodies.

This updated 2007 report continues to examine eutrophic conditions into the 2000s. It attempts 

to look at changes that occurred in the past decade, and analyze the Nation’s progress in addressing 

what we now see as a ubiquitous problem. Coastal eutrophication is a global problem not limited 

to U.S. coastal waters. This report highlights the nutrient contamination in selected coastal systems 

throughout the U.S., Europe, Australia, and China in an effort to share what we know about the 

development of eutrophication, and to provide successful solutions to better manage the problem. 

In addition to gaining a broader view of the issue, this report has enhanced and improved 

upon earlier work in other ways. The innovative assessment approach using the experience and 

knowledge base of experts from around the Nation has been transformed into a web-enabled 

tool. This web-based tool allows investigators to share data and information effectively and 

communicate in a standardized manner. This represents one of few instances where web-based 

communication has been accomplished for ecological monitoring on such a large scale (accessible 

at http://ian.umces.edu/neea or http://www.eutro.us). Effective communication is vital because 

the assessment will be updated on a periodic basis. The development of a complementary human 

use/socioeconomic indicator is also a significant enhancement designed to bridge the gap between 

scientific and public interest. 

Additionally, this report provides a valuable context for a number of ongoing and planned 

activities designed to address estuarine eutrophication such as the multi-agency National Coastal 

Condition Report and the Gulf of Mexico Alliance Governors’ Action Plan. 

We encourage you to use this work to stimulate further scientific and management efforts to 

protect our precious coastal resources. 

John H. Dunnigan

Assistant Administrator

for Ocean Services and 

Coastal Zone Management

Dr. Donald F. Boesch

President 

University of Maryland,

Center for Environmental Science
table of contents

 

i Key Findings 

iii Executive summary

1 Chapter 1 • 

 Introduction and background

2 Understanding eutrophication

4 Conducting a national assessment

5 Updating the assessment

6 Developing an online tool for assessment updates

8 Application of the update

9 Chapter 2 • Approach

10 Evaluating eutrophication 

12 Determining influencing factors 

14 Determining the eutrophic condition 

19 Determining future outlook 

20 Assessment of estuarine trophic status (ASSETS)

21 Chapter 3 • National assessment

22 Summarizing the nation’s eutrophic condition 

24 Exploring physical characteristics on a national scale 

28 Assessing eutrophication on a national scale 

38 Eutrophication and climate change

39 Chapter 4 • Regional Summaries

40 North Atlantic region 

47 Mid-Atlantic region

55 South Atlantic region 

64 Gulf of Mexico region 

74 Pacific Coast region 

83 Chapter 5 • Case studies 

84 Examining eutrophication in other systems: case studies 

86 Boston, Massachusetts 

88 Casco Bay, Maine 

92 Corsica River, Maryland 

95 Hood Canal, Washington 

99 Laguna Madre, Texas 

101 Long Island Sound, Connecticut and New York 

104 Looe Key, Florida 

106 Maryland Coastal Bays 

109 Mississippi-Atchafalaya River Plume, Louisiana 

111 San Francisco Bay, California 

113 Skidaway River estuary, Georgia 

115 Tampa Bay, Florida 

118 Waquoit Bay, Massachusetts 

121 Changjiang (Yangtze) Estuary, China 

124 Jiaozhou Bay, China 

127 Mondego River, Portugal 

131 Moreton Bay, Australia 

134 Venice Lagoon, Italy 

139

140

142

Chapter 6 • 

 Improvements to the assessment

Improving the method 

Comparing the EPA National Coastal Assessment with the 

NEEA 

144

153

Determining typology 

Developing a human-use indicator for Barnegat Bay 

157 Chapter 7 • 

 conclusions and CONSIDERATIONS for 

Monitoring, Research, and Management 

A1 acknowledgements 

A3 references

A5 Data sources 

A7 estuary summaries

Estuary summary introduction

North Atlantic region

Mid-Atlantic region

South Atlantic region

Gulf of Mexico Region

Pacific Region