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Dissolved Oxygen Report
The Workgroup has retained a consulting engineering team
led by HDR Consulting, Huff and
Huff Inc and Interfluve Inc. to conduct a study identifying ways to
improve dissolved oxygen levels in Salt Creek and the
East Branch of the DuPage River. A web site for the
project has been developed:
West Branch Report (Still being
developed)
East Branch Report
Salt Creek Report
Continuous Dissolved Oxygen
Monitoring Program
The DuPage River Salt Creek
Workgroup (DRSCW) launched the continuous dissolved
oxygen (DO) monitoring network in 2006. Prior to that
DO was monitored continuously at only one site in the
Upper DuPage, at the City of Wheaton under the authority
of Wheaton Sanitary District and four on Salt Creek
under the authority of Metropolitan Waster Water
Authority of Greater Chicago (MWRDGC). In 2009 there
were three on the West Branch, five on the East Branch
and eight on Salt Creek. The attached Map shows the
2009 distribution of permanent DO stations in the West
and East basins of the DuPage River and of Salt Creek
The sites maintained by the DRSCW
are equipped with a HydroLab DS 5X equipped to collect
data on DO, pH, conductivity and water temperature.
Stations have a sample interval of one hour and run from
April through to October (the seasonal period recognized
as containing the lowest annual levels of stream DO).
The project functions under a quality assurance plan
agreed on with the Illinois Environmental Protection
Agency.
Why continuous monitoring? DO is a
water quality indicator that oscillates throughout the
day as alga and other aquatic vegetation add or remove
oxygen from the water column, a phenomena called diurnal
variation. Variation during 24 hours can be very large
as seen in adjacent graph. These sites are on the West
Branch of the DuPage River and the variation revealed in
the box and whisker plots shows that the variation was
largest at WBMG, a site impounded by a dam. Such
conditions are conducive to algae growth and typically
experience low DO values in the mornings.
DO Sonde in Hanover Park, West Branch DuPage River.
The platform used by the DRSCW is equipped to collect
data on DO, conductivity, pH and water temperature
DO variation on the West Branch of the DuPage River at
Hanover Park (WBAD) and McDowell Grove Naperville (WBMG)
2007. Note the larger spread of DO in the McDowell
grove example;
Included here are other links that
have been generated as part of this study:
This report was prepared in part using U.S.
Environmental Protection Agency funds under Section 319
of the Clean Water Act distributed through the Illinois
Environmental Protection Agency. The findings and
recommendations herein are not necessarily those of the
funding agencies.
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