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Nonpoint Source Water Pollution

Nonpoint Source > Watershed Assessment > Impaired Waters - Integrated Report > External Data and Listings > How Might Your Data Fit Into the Framework? How Might Your Data Fit Into the Framework?

The mission of OWQ 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. This mission is consistent with the goal of the CWA to restore and maintain the chemical, physical and biological integrity of the nation’s waters. The CWA is implemented by IDEM through various programs within OWQ. Depending on the nature and quality of your data set, results may be used by one or more of the following programs:

  • Integrated Report program (CWA Sections 305(b) and 303(d))
  • Total Maximum Daily Load (TMDL) program
  • Nonpoint Source grant programs (CWA Sections 205(j) and 319)
  • Rule 13 Municipal Separate Storm Sewer Systems program (MS4)
  • State Revolving Loan Fund program
  • National Pollutant Discharge Elimination System (NPDES)
  • Regional Sewer District program

The external data framework is a tiered system, based on U.S. EPA’s graded approach to data quality, which recognizes that the quality of data should be commensurate with the intended use of those data. For example, regulatory decisions (Level 3) require the highest quality data – equivalent to that collected by IDEM OWQ – while the data quality requirements for nonregulatory uses (Levels 1 and 2) are not as stringent.

Table 1: Summary of the three data levels
Data Quality Level Data Quality Characteristics Potential Uses of the Data by OWQ programs
3
  • High level of scientific rigor;
  • Data quality must be documented and comparable to OWQ;
  • Study designs may vary but must be appropriate for the intended use of the data;
  • Sampling and analytical methods must be equivalent to those used by OWQ;
  • Internal quality assurance (QA) required, external QA may be required, QA results must be available to OWQ upon request; and,
  • Data must be associated with a particular site on a particular waterbody; Geographical location information in a GIS-compatible format is required.
  • TMDL modeling;
  • CWA Section 305(b) water quality assessments;
  • CWA Section 303(d) listing decisions;
  • Removal from the State’s 303(d) Impaired Waters List;
  • Determining representative background conditions for the purposes of developing NPDES permits; and,
  • Any Level 1 or Level 2 use
2
  • Medium level of scientific rigor;
  • Data quality must be documented;
  • Study designs may vary but must be appropriate for the intended use of the data;
  • Sampling and analytical methods may or may not be equivalent to those used by OWQ;
  • Internal QA is required with optional external QA; and,
  • Data must be associated with a particular site on a particular waterbody and geographical location information is required.
  • Supplementary information for use in planning and prioritization of OWQ monitoring efforts or TMDL development;
  • Demonstrating the effectiveness of TMDL implementation efforts;
  • Demonstrating the effectiveness of watershed management plan implementation efforts over time;
  • Baseline data collection for analysis of trends over time;
  • Watershed management planning;
  • Demonstrating compliance with minimum control measures specified in MS4 permits;
  • Establishing need for low interest loans to assist with regional sewer and water district formation ; and,
  • Any Level 1 use.
1
  • Low level of rigor, but based on sound science;
  • Data quality documentation is optional;
  • A wide variety of study designs are acceptable;
  • QA is optional; and,
  • Data must be associated with a particular waterbody or watershed and geographical location information is optional.
  • Education and raising awareness of water quality issues;
  • Supplementary information for TMDL development; and,
  • Supplementary information for development of Indiana’s integrated water monitoring and assessment report.

Monitoring activities are typically determined based on an organization’s unique project needs, not the needs of IDEM OWQ. However, if your organization is currently in the process of planning or will be developing a monitoring plan, it may be possible to design a study to produce data that meets both needs, increasing the value of your efforts. If your organization already has a monitoring program in place, it may be possible to monitor in a way that provides data that will also meet OWQ’s needs with only minor adjustments to your current activities.

This document provides generalized requirements regarding timelines for data submission, how your data will be reviewed, and the types of technical assistance available. Specific guidance in separate sections for each data quality level including:

  • How your data might fit into OWQ processes;
  • Minimum documentation required for data submission;
  • Sampling and analytical methods;
  • Site location considerations and information on frequency and timing of monitoring activities;
  • Minimum data requirements;
  • Quality control procedures and data quality requirements; and,
  • Minimum reporting requirements.