 |
Investigating Episodic Contaminant Transport in Estuaries
|
Project Title: Developing and applying a new in situ technology for the investigation of episodic contaminant transport events within estuaries
Research Locations: Narragansett Bay, RI
Last Update: 2-01-02
Seasonal and episodic events such as tidal and wind driven-currents, rainstorms, channel dredging and ship activity may lead to the resuspension of sediments and significant changes in the concentration of dissolved oxygen, chemical contaminants and nutrients in coastal waters. The consequences of event-driven chemical variability include eutrophication, hypoxia, harmful algal blooms and fisheries disruption. This project will employ a combination of traditional surve techniques and innovative towed instruments to characterize the changes in water and sediment quality in estuaries.
Approach
To characterize contaminant transport, researchers used traditional survey techniques (e.g., sediment traps) as well as a new sensor package (the XZ-Profiler, see figures) custom designed, in part, for this project. The
sensor package can be towed behind an underway vessel (in undulating or depth-
keeping mode), allowing for continuous measurements of copper, iron, nitrate, nitrite, phosphate and ammonium as well as salinity, temperature, dissolved oxygen, pH, chlorophyll and turbidity. At the same time, Acoustic Doppler Current Profiler surveys were used to better characterize spatial circulation patterns. In this way, plumes of resuspended contaminants could be tracked and represented in three dimensions.
Results
- Field tests have confirmed the viability and utility of the newly developed sensor package, which is now commercially available (for details, see "Application").
- This research provides strong evidence that plumes of resuspended contaminants are important sources of toxics and nutrients in estuaries. The adjacent figure shows 2D data depicting an iron plume observed emanating from a point source at a scrap iron loading facility in Providence, Rhode Island.
The Effect of Episodic Events
As part of this project, researchers will perform real-time, in situ
analyses of water properties before and after two storms: one
during the summer and one during the winter. It is hoped that
these data will illuminate the effect of episodic events such as
storms and dredging operations.
On the Market
The XZ-Profiler includes instruments developed by SubChem
Systems, Inc. and WET Labs, Inc. as well as a Sea-Bird Electronics
CTD sensor. The tow body was manufactured by Sea Sciences. The
entire system is available from SubChem Systems, a principal
partner on the CICEET project.
|
Project Coordinator
|
John King University of Rhode Island (401)874-6182 jking@gsosun1.gso.uri.edu |
|
Industry Partner
|
Alfred Hanson SubChem Systems,Inc. (401)874-6294 http://subchem.com hanson@subchem.com |
|
Start -End Date:
|
09/01/2001 -09/01/2002
|
|
NERR Reserve(s):
|
Narragansett Ba ,RI
|
| For more information: |
Dolores Jalbert Leonard Phone: (603) 862-3685 Email: dolores.leonard@unh.edu |