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Boston Harbor
and Massachusetts Bay
Massachusetts
Water Resources Authority
Management
and use of a long-term water quality monitoring database for Boston Harbor
and Massachusetts Bay
Suh
Yuen Liang, Doug Hersh, Wendy Leo, Environmental Quality Department, Massachusetts
Water Resources
Authority
Database Management
The Massachusetts
Water Resources Authority (MWRA) maintains an extensive environmental
database, which consists of long-term monitoring data for Boston Harbor
and Massachusetts Bay, and effluent testing data for MWRA treatment plants
and combined sewer overflow treatment facilities. To increase the awareness
and to encourage the use of the MWRA environmental database, in this presentation
we highlight (1) data quality assurance and control, (2) data sources,
database management, and application, (3) studies and sampling locations,
and (4) examples of data use.
Figure
1. Most
of the monitoring data have been collected by MWRA and its consultants
during the past decade. These data are under stringent quality assurance
(QA) and quality control (QC) following the Deming/Shewhart model
for quality management ).
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Figure
2. Data checking takes place in many stages including laboratory data
collection, data entry, QC check plots Figure
2. and statistical summary of data, QA review of data, and loading
to database.
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Figure
3. Data
from other agencies and organizations are included in the database
only when the data are thoroughly documented.
All data are stored in an Oracle relational database management system.
Sources and users of the data are diagrammed.
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Figure
4. Major
categories of monitoring data in the database are: water quality,
effluent chemistry, fish and shellfish chemistry and pathology, sediment
contaminants, plankton abundance, and benthic infauna. Sampling locations
in relation to each monitoring study are shown.
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Examples
of data use by a broad
range of clients are shown in Figures 5 through 10, below.
Figure
5a. A
time series (open symbols) from September 1997 to December 2001.)
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Figure
5b. SeaWIFS-derived
annual mean chlorophyll concentration in Massachusetts Bay.
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Figure
6. Receiver
operating characteristic (ROC) curves of previous day Enterococcus
density (a) and 48-Hour antecedent rainfall (b) for Constitution Beach.
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Figure
7. Observed
(black circles) and predicted (red line) Enterococcus counts between
1996 and 2003 at Deer Island (a) and Nut Island (b) outfalls regions.
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Figure
8. Data
from across studies are synthesized to improve our understanding of
ecological processes in Mass. Bay.
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Figure
9. Surface
temperature (color gradients) and current (arrows) in summer 1999
from Massachusetts Bay hydrodynamic model.
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Figure
10. A two-dimensional hydrodynamic and water quality model of the Lower
Charles River in Boston.
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Summary
MWRA water quality
database has been used intensively for management internally and for compliance
with MWRAs discharge permit and court orders. It also serves as
a data warehouse for the public and the academic community interested
in the health, ecology and physical characteristics of Boston Harbor and
Massachusetts Bay. Water quality data and reports are available to the
public upon request. For complete list of the reports about our water
quality monitoring studies, please visit our Technical Reports page.
References
For
more information, email the Environmental
Quality Department.
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