Eutrophication (nutrient pollution) in Coastal Waters of the US and Elsewhere

Eutrophication (nutrient pollution) in Coastal Waters of the US and Elsewhere


Eutrophication (nutrient pollution) in Coastal Waters of the US and Elsewhere

Dr. Suzanne Bricker, Center for Coastal Monitoring and Assessment, National Centers for Coastal Ocean Science, NOAA

5:45pm reception (with refreshments) followed by the seminar at 6:00 in caputo 210.


Coastal water quality problems related to eutrophication, also called nutrient pollution, such as low dissolved oxygen, harmful algal blooms and seagrass loss are observed in coastal waterbodies around the world. Results of the National Estuarine Eutrophication Assessment show that these problems are observed at moderate to serious levels in 65% of the U.S. estuaries that were evaluated.  In most places there has been no change in condition in the decade from the early 1990s to the early 2000s and the majority (65%) of systems that were evaluated are expected to show worsening conditions in the future.  The causes of observed eutrophic conditions are typically human related land-based nutrient loads, mostly from non-point sources such as agricultural and urban runoff. However, the physical characteristics of an estuary, such as the amount of freshwater inflow and the tidal range, can influence development of problems with consequent implications for management.  Application of the same method to waterbodies in Europe, Asia and Australia show that eutrophication is a global issue. While reductions of nutrients from land based sources have reduced problems in some areas, other alternative management measures are being explored such as bioextraction of nutrients through shellfish aquaculture and restoration of oyster reefs.

Assessment results are intended to provide decision support for management, but the assessment indicators often fail to convey the impact that degradation has on human uses of coastal systems. An indicator related to human use value was developed by combining bio-physical indicators with indicators of the value related to human use, in this case using recreational fish catch. The average fish catch in the system for which the indicator was developed showed a 26% reduction in catch as a result of low dissolved oxygen impacts with an economic loss to fishermen of $25.4 million a year for a single species.

Brief Bio

Dr. Suzanne Bricker of NOAA's NCCOS Center for Coastal Monitoring and Assessment received a BA in Biology from Northwestern University and a PhD in Oceanography from the University of Rhode Island. For the past 20 years she has been involved in development and application of assessment methods for determining the impact of nutrients on estuarine and coastal water bodies as lead for NOAA's National Estuarine Eutrophication Assessment. The intent is to provide resource managers with the data and information they need to manage coastal resources successfully. Through collaborative work, she and her colleagues were able to demonstrate that this global problem has similar and predictable symptoms throughout the world. Most recently her work has included pursuit of alternative management measures, such as shellfish aquaculture, that complement traditional land-based management measures. For additional information go to and  and