Indiana Surface Water Quality Monitoring Strategy

The first Surface Water Quality Monitoring Strategy was developed in the 1990’s to better direct the collection of data used in the assessment of surface water quality in Indiana’s rivers, streams, and lakes for designated water uses, such as recreation, and related uses such as human consumption of fish, and the overall health of aquatic life as it is affected by water quality.

The 2017-2021 Water Quality Monitoring Strategy refines the previous Indiana Water Quality Monitoring Strategy 2011-2019, which marked a significant change in monitoring designs. It was developed by an interdisciplinary work group comprised of staff from several programs within the Office of Water Quality (OWQ), including monitoring staff responsible for collecting the water quality data needed to meet Indiana Department of Environmental Management (IDEM) water management needs. The OWQ collects surface water quality, biological, and habitat data for the following purposes:

  • To fulfill requirements of the CWA § 305(b), § 303(d) and § 314 to assess all waters of the state to determine if they are meeting their designated uses and to identify those waters that are not.
  • To support OWQ programs including water quality standards (WQS) development, National Pollutant Discharge Elimination System (NPDES) permitting, and compliance.
  • To support public health advisories and address emerging water quality issues.
  • To support watershed planning and restoration activities.
  • To determine water quality trends and to evaluate the performance of programs.
  • To engage and support a volunteer monitoring network across the state.

The following monitoring programs are employed to achieve the above objectives:

  • Probabilistic monitoring in one basin/year on a 9-year rotating basin cycle.
  • Fixed Station monitoring at 165 sites across the state (2 added in 2014 for Natural Resource Conservation Service (NRCS) National Water Quality Initiative (NWQI).
  • Fish tissue and sediment contaminants monitoring on a 5-year rotating basin cycle.
  • Targeted (watershed characterization) monitoring for Total Maximum Daily Load (TMDL) reassessments and development, watershed baseline planning, and performance measures determinations.
  • Cyanobacteria monitoring of 10-12 lakes.
  • Special studies such as hydrograph controlled release facilities (HCR) and remediation follow-up sampling.
  • Thermal verification studies.
  • Hoosier Riverwatch (HRW) program citizen volunteer monitoring.

This WQMS identifies key water quality monitoring objectives and the monitoring approaches used to collect the data necessary to meet them. The activities related to U.S. EPA priorities or requirements and those related to the protection of human health are ranked as IDEM’s primary priorities. All others are ranked as secondary priorities based on resource constraints and other factors including the degree to which they meet the OWQ mission:

The OWQ mission is to monitor, protect, and improve Indiana's water quality to ensure its continued use as a drinking water source, habitat for wildlife, recreational resource and economic asset.

IDEM’s WQMS is developed to facilitate an adaptive management process in order to ensure that the monitoring programs are providing the data required for IDEM program management as well as to meet emerging concerns. OWQ plans to revise the WQMS every five years and will evaluate its monitoring programs annually to determine what worked well and what was problematic in order to modify or improve logistics. IDEM will work with U.S. EPA to determine the appropriate timelines for formal review and approval of future revisions to this WQMS.