The Illinois State Water Survey (ISWS) has collected significant amounts of water quality data over the 100+ years of its existence.
From 1945 to 1978, a state-supported program monitored water quality in Illinois streams and rivers every five years. In addition, numerous research projects supported by state funds and other grants and contracts have collected water quality data across Illinois for short periods.
This website was created to provide access to these various datasets in a standardized format.
The initial version of this website will contain data collected mainly from the Illinois River. As resources allow, additional datasets will be
reviewed, compiled, and included in this database. The table below provides a brief description of the geographic and temporal extent of the
datasets available thus far; this information will be updated as additional datasets are included (see the Database Summary
a more detailed overview of the database contents).
As of 8/15/08, the Water Quality Database contains data from the following projects:
ISWS SEPA In-stream Dissolved Oxygen StudyMeasurements of DO, temperature, pH, and conductivity were made to determine the
effect operation of Sidestream Elevated Pool Aeration (SEPA) stations had on DO levels in the Calumet waterway system. Data were collected
in 1995-1996 using continuous monitoring equipment (Sondes) and supplemented with cross-sectional DO and temperature measurements.
(ISWS Contract Report 2000-02, 2000)
||Illinois River above Joliet
||ISWS Contract Report 2000-02
ISWS Illinois River at Peoria MonitoringA long-term monitoring program collecting water quality data on the
Illinois River at Peoria Illinois from 1965-1994. Samples were collected weekly and analyzed for multiple WQ parameters, bacteria, and
algal populations. Most samples were collected mid-morning. These data provide a historical long-term benchmark on water quality characteristics
of the Illinois River at Peoria. Limited data collection continued until 1999.
||Illinois River at Peoria
ISWS Upper Illinois Waterway StudyWater quality data was obtained from field surveys made primarily during July,
August, and September of 1971 and July 1972 on the upper part of the Illinois Waterway from Chillicothe (milepoint 179.0) to Lockport
(milepoint 292.1). A limited amount of water quality data was collected during several days in late October and early November 1971,
and bottom sediment oxygen demand characteristics were investigated during August through November 1972. A limited amount of information
related to bacterial and algal characteristics of the upper waterway were also gathered. These data were collected to evaluate the
relationship between oxygen demand and available DO resources within the waterway. (ISWS Report of Investigation 79, 1975).
||Upper Illinois River
||ISWS Report of Investigation 79