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Nonpoint Source Water Pollution

Nonpoint Source > Watershed Assessment > Impaired Waters - Integrated Report > External Data and Listings > Framework Requirements for Level 3 Data Framework Requirements for Level 3 Data

Potential Use of Your Data by OWQ

In addition to any Level 1 or Level 2 use, water quality data meeting the data quality and other requirements for Level 3 may be used by OWQ for the following:

  • TMDL modeling;
  • CWA Section 305(b) water quality assessments;
  • CWA Section 303(d) listing decisions;
  • Demonstrating the effectiveness of any implementation effort such that one/more impairments may be removed from the State’s 303(d) Impaired Waters List; and,
  • Determining representative background conditions for the purposes of developing National Pollutant Discharge Elimination System (NPDES) permits.

The designated uses outlined in Indiana’s water quality standards as well as the narrative and numeric criteria to protect them provide the foundation for most of OWQ’s Level 3 decision making processes. Therefore, data submitted for Level 3 uses must relate to a water quality standard or designated use articulated in the state’s water quality standards.

Due to the regulatory nature of most Level 3 uses, any water chemistry and biological data as well as field measurement data submitted for consideration in OWQ’s Level 3 processes must have a high level of scientific rigor.

Data Quality Documentation and OWQ Review

Data submitted to IDEM for Level 3 uses must include a detailed study plan or QAPP. Because the data quality needs of your organization may differ from those of OWQ programs, OWQ must determine whether your data can be reliably used for Level 3 decisions. This is accomplished by reviewing the documentation provided with your data set. Table 4 provides generalized requirements for Level 3 data. More specific acceptance criteria for Level 3 uses are provided in following sections.

Table 5: Generalized acceptance criteria for Level 3 data.
Characteristics of the Data Set Generalized Acceptance Criteria for Level 3 Data
Age of data In accordance with OWQ’s consolidated assessment and listing methodology (CALM), data must be less than or equal to five years of age to be considered for Level 3 uses.
Sampling design Sampling design may be either synoptic or probabilistic. OWQ will review the sampling design to determine whether the study provides representative data for the purposes of Level 3 decision making processes. Although statistical assessments at the watershed scale may be submitted, for most Level 3 uses the data will be applied to the waterbody on which they were collected and for which they are representative./
Comparability Data submitted for Level 3 uses must be equivalent to data collected by OWQ. All data submitted for Level 3 will be reviewed to ensure comparability with IDEM’s sampling and analytical methods and QC procedures.
Geographic information Location information is required and must be submitted electronically in GIS-compatible format. Site location information must be sufficient to identify the specific waterbody to which the water quality results apply.
Submission requirements (e.g. formatting, required components, etc.) Any data provided for Level 3 uses must be submitted electronically. U.S. EPA contract laboratory forms and contract laboratory format are preferred. Templates are provided for organizations that do not use the contract laboratory system. Raw data, QC data, bench sheets and chromatograms (if applicable) need not be included as part of the analytical report but must be available upon request.
Documentation of data quality (metadata for the data set) A QAPP that conforms to U.S. EPA Requirements for QA Project Plans (QA/R-5) is preferred. Other documentation may be acceptable if it provides sufficient information to ascertain the quality of your data set through comparison with OWQ’s Level 3 acceptance criteria.

Sampling and Analytical Methods

Generally, decisions regarding the specific sampling and analytical procedures to be used are driven by an organization’s intended use for the data. Due to the regulatory nature of Level 3 uses, data submitted by an external organization may be considered for Level 3 uses only if the organization used sampling and analytical methods directly comparable to those employed by OWQ.

Field measurements are collected in accordance with IDEM Assessment Branch’s standard operating procedure (SOP) Manuals for the Surveys Section and the Biological Studies Section. Direct reading equipment and observations that do not require data reduction are recorded on field sheets. Your organization’s field sheets need not be identical to those used by OWQ. However, they should contain as much of the same information as possible as they may be requested by OWQ to resolve any questions regarding your data.

Field observations requiring calculations may be reduced in the field and validated afterward. External organizations submitting field data for Level 3 uses should conduct the internal quality control verification process prior to submission of their data to IDEM and will be expected to include the results of their verification process in their data submission package. OWQ’s quality control procedures for field data are outlined in Appendix F of the assessment branch SOP manual.

A list of the specific parameters that may be considered for Level 3 uses and approved analytical methods specified in the Assessment Branch quality assurance project plan (QAPP) is provided in Appendix C. This list is not comprehensive. Most Level 3 processes involve comparing results to a water quality criterion. Therefore, the framework focuses specifically on those parameters for which criteria exist in Indiana’s water quality standards and for which OWQ has established assessment methodologies.

Organizations interested in submitting results for any parameters not shown are encouraged to contact the external data coordinator. Assistance in determining if the sampling and analytical methods they are using are consistent with those required for Level 3 uses is available.

Site Location Considerations

Generally, the designated uses outlined in Indiana’s water quality standards and the narrative and numeric criteria are equally applicable to all waters of the state. Therefore, data collected on any surface water in Indiana are potentially useful for Level 3 processes.

It is anticipated that the monitoring conducted by most external organizations is targeted in nature. However, statistical studies for which sites are selected randomly may also be useful to OWQ for Level 3 processes. Although the data from such studies will be applied on a site-specific basis for the purposes of Level 3 decision-making processes, statistical conclusions may also be appropriate for Level 2 uses such as augmenting agency information for developing TMDLs or reports to U.S. EPA.

Frequency and Timing of Monitoring Activities

Although the frequency and timing of your monitoring activities is driven by your organization’s specific project needs, it may be possible to monitor in a way that provides data that will also meet OWQ needs with only minor adjustments to your sampling plan.

Few Level 3 decision making processes have specific requirements regarding when samples should be collected. The only exception to this is bacteriological monitoring, which must be conducted during the recreational season, April through October, as defined in Indiana’s water quality standards. Monthly grab samples collected during this period may be used for Level 3 decisions. However, collecting five samples, equally spaced over a 30 day-period is preferable because it provides sufficient data to calculate a geometric mean.

For all types of data, OWQ will review the timing and frequency of monitoring activities to determine the usability of data in OWQ processes. Some time periods that are helpful are listed below:

  • The Watershed Monitoring program conducts sampling for water chemistry under different flow regimes during three distinct timeframes: May through June, July through August and September through October. This program also conducts fish community assessments, macroinvertebrate community assessments and habitat assessments once a year at these same sites during the seasonal low-flow timeframe from July through October;
  • The Nutrients Monitoring program collects water chemistry and two measures of algal biomass, chlorophyll a and ash free dry mass at many of the same sites selected for the Watershed Monitoring program. This data is collected three times per year in late spring, summer and fall;
  • The Fixed Station program collects water chemistry and bacteriological samples and field analytical data monthly at fixed station locations throughout the state;
  • The Trace Metals program collects samples for dissolved metals analyses at selected sites throughout the state on a quarterly basis. This program also collects field analytical data and samples for some non-metal parameters;
  • The Fish Tissue Contaminant Monitoring program collects samples once at each site per year; and,
  • The E. coli Monitoring program monitors each site five times with sampling events equally spaced over a 30-day period.

Fact sheets for these and other OWQ monitoring programs are available through the IDEM web sites for the Surveys Section and the Biological Studies Section, both of which reside in the OWQ Assessment Branch.

Minimum Data Requirements

Most Level 3 decision making processes are based on the designated use assessments conducted as part of the OWQ’s CWA 305(b) assessment process. Generally, if the data set submitted by your organization includes the appropriate parameter and contains a sufficient number of results to determine support of one or more designated uses, it may be considered for other Level 3 uses. Minimum data requirements for each type of decision and the appropriate parameter type are provided in Table 5.

Table 6: Minimum Data Requirements for Level 3 Uses
Parameter Type Minimum Data Requirements Decision to Be Made
Toxicants and conventional inorganics Minimum of three measurements Determining aquatic life use support in rivers and streams;

Determining drinking water use support for waters that serve as a public water supply; and,

Determining representative background conditions for NPDES permits.
Nutrient parameters Minimum of three measurements.

Two or more of parameters must have been exceeded on same date in order to classify a waterbody as impaired.
Determining aquatic life use support in rivers and streams; and,

Determining representative background conditions for NPDES permits.
Benthic aquatic macroinvertebrate community and QHEI Minimum of one measurement, preferably with corresponding qualitative habitat use evaluation (QHEI) score Determining aquatic life use support in rivers and streams
Fish community (IBI) and QHEI Minimum of one measurement, preferably with corresponding qualitative habitat use evaluation (QHEI) score Determining aquatic life use support in rivers and streams
Mercury and PCBs in fish tissue One actual concentration value (including estimated values above the method detection limits) Determining fishable use support (human health); and,

Determining representative background conditions for NPDES permits.
Bacteria (E. coli) Minimum of ten grab samples or one geometric mean result calculated from five equally spaced samples over 30 days. Sampling must have been conducted during recreational season (April-October) Recreational use support (human health); and,

Determining representative background conditions for NPDES permits.
Total phosphorus and chlorophyll a Minimum of three total phosphorus results with corresponding chlorophyll a results collected over three years (consecutive or nonconsecutive). Recreational use support (aesthetics) in lakes and reservoirs
Toxicants Minimum of three measurements Drinking water use support for waters that serve as a public water supply
Bacteria (total coliforms) Minimum of ten grab samples or one geometric mean result calculated from five equally spaced samples over 30 days. Drinking water use support for waters that serve as a public water supply

Quality Control Procedures

OWQ’s Assessment Branch QAPP specifies the quality control checks for field measurements and laboratory data required for data to be considered for Level 3 uses. Field quality control checks are measures used to assess the quality of field data. Laboratory quality control checks are measures used to assess the quality of the data results from the analytical procedures performed in the laboratory.

OWQ’s quality control checks are summarized in Appendix C so that external organizations can determine if their sampling and analytical procedures will produce data that can be used for Level 3 uses. In some cases, only minor alterations to existing processes can result in broader use of your organization’s data.

Data Quality Requirements

OWQ has established acceptance criteria in order to help ascertain whether data quality of your data set is sufficient for Level 3 uses. The monitoring conducted by external organizations is typically driven by different needs than those of OWQ. Given this, data sets submitted by external organizations may have different data quality objectives than OWQ. Thus, when external data are received, OWQ must determine whether those data quality objectives will result in data that can be reliably used for Level 3 decisions.

This is accomplished by reviewing submitted data against acceptance criteria. These criteria specify the data quality needed for Level 3 decision making processes. In addition to the generalized acceptance criteria in Table 4, OWQ has established specific acceptance criteria based on the type of data submitted for Level 3 data uses. These criteria are based on the following data quality indicators: precision, bias, accuracy, representativeness, comparability, completeness and sensitivity.

OWQ’s acceptance criteria for laboratory analytical results for water and fish tissue samples are provided in Appendix C and are expressed in terms of precision and accuracy. In addition to precision and accuracy, OWQ will review your data submission for other data quality indicators:

  • Comparability: Are the sampling and analytical methods comparable to OWQ methods?
  • Representativeness: Is the study design capable of providing representative data for the intended Level 3 use; and,
  • Completeness: Does the information meet the minimum data requirements for a given Level 3 use?

Note that for laboratory data sets, qualified results may be acceptable for Level 3 uses. Therefore, it is important to include in your documentation definitions for any data qualifiers and flags associated with your data. In addition, laboratory quality control results must be available to OWQ upon request in order for your results to be used in any Level 3 processes.

Acceptance criteria for biological community data is based on the sampling methods used, the sensitivity of the analytical methods (i.e. the taxonomic level of identification) and the level of taxonomic expertise of the individual performing the identifications. More detailed information on OWQ’s acceptance criteria for biological data is provided in Appendix C.

Data Reporting Requirements

Any data provided for Level 3 uses must be submitted electronically. U.S. EPA contract laboratory forms and contract laboratory format is preferred. Templates are provided for organizations that do not use contract laboratory system. Raw data, QC data, bench sheets and chromatograms (if applicable) need not be included as part of the analytical report but must be available upon request.

4) Indiana’s water quality standards are provided in Indiana Administrative Code (IAC 327, Article 2).