Integrated Water Monitoring and Assessment Report

Section 305(b) of the Clean Water Act (CWA) requires the Indiana Department of Environmental Management (IDEM) to assess and report on whether Indiana waters support the beneficial uses designated in Indiana’s water quality standards. IDEM’s CWA Section 305(b) assessments are made in accordance with IDEM’s Consolidated Assessment and Listing Methodology (CALM) by comparing existing and readily available water quality data to the applicable water quality criteria in the State’s water quality standards.

The large majority of the data IDEM uses in its 305(b) assessments are collected by IDEM staff using a rotating basin approach. IDEM has divided Indiana into nine major water management basins and monitors one major basin each year. IDEM staff assess the data collected in each basin the following year.

In addition to agency-collected data, IDEM solicits data through its External Data Framework from external organizations and agencies, including the United States Geological Survey, Indiana University’s School of Public and Environmental Affairs, and the Indiana State Department of Health. IDEM also solicits water quality data from other colleges, universities and local organizations, such as county health departments, watershed management groups and cities and towns.

IDEM’s water quality assessment results are reported to U.S. EPA every two years through the Indiana Integrated Water Monitoring and Assessment Report, which describes the condition of Indiana’s lakes, streams, ground water and its Lake Michigan shoreline.

Indiana’s 2018 Integrated Water Monitoring And Assessment Report

IDEM will submit its 2018 Integrated Report to U.S. EPA on or before August 31, 2018.   IDEM published the notice of its 90-day public comment period for the draft 2018 303(d) List of Impaired Waters and Consolidated Assessment and Listing Methodology (CALM) used to develop it, in the Indiana Register on April 11, 2018. 

The 90-day public comment period is currently underway and will close on July 10, 2018. IDEM will accept public comments during this time. Interested parties will find all the information they need to review and provide comment on the draft 2018 303(d) list and CALM on IDEM’s web page for the 303(d) list

After the public comment period closes, IDEM will review and develop responses to all comments received and will include the public comments and its responses to U.S. EPA as part of IDEM’s 2018 IR.

Indiana’s Integrated Water Monitoring and Assessment Reports for Previous Cycles

Indiana’s 2010 Integrated Water Monitoring and Assessment Report and earlier versions are available upon request by contacting IDEM’s Integrated Report Coordinator.