Methodology and Guidance: 2022 Integrated Report

States are required under the Clean Water Act (CWA) Section 303(d) to compile a list of waters that do not support their designated beneficial uses and submit the list in a biennial Integrated Report to the Environmental Protection Agency (EPA) for approval. Beneficial uses include drinking water, recreation, aquatic life, and agriculture.The 303(d) list identifies the pollutant(s) causing the impairment and prioritizes the development of Total Maximum Daily Loads (TMDLs) to meet state water quality standards and support beneficial uses.

The draft assessment methodology document describes Utah’s assessment methods for the 2022 IR cycle. The document complies with federal regulations that require states to evaluate all existing and readily available data against both narrative and numeric criteria when developing their 303(d) lists.

The Draft 2022 IR Assessment Methods document was open for a public comment period (174 KB) from January 20, 2021, to February 26, 2021. Any comments on assessment methods received after the close of the comment period are considered out of scope for the 2022 Integrated Report. DWQ has reviewed the feedback submitted during the public comment period and provided a formal response to comments along with the final assessment methods for the 2022 Integrated Report.

Summary of Methods Changes

Final 2022 303(d) Assessment Methods – Changes from previous version and draft

SectionSubsectionPage RangeTiming of ChangeNature of Change
Assessment Process and Time FramesDeveloping the Methods/Public Review of the Methods Process and Schedule26Draft 303(d) MethodsEdits to timing details for 2022 Integrated Report.
Scope of the AssessmentWaterbody Types32Response to CommentsEdits to language describing river and stream waterbody type.
Scope of the AssessmentAssessment Units32Draft 303(d) MethodsRemoved a section on required datums used for assessment unit shape files. Changed AU stream mileage estimation to perennial stream miles only.
Data QualityCredible Data Matrices37-38Response to CommentsChanged calibration and sonde requirements to reflect sonde specifications typical of equipment used by DWQ staff and other water quality monitoring entities.
Data Submission ProcessPeriod of Record43Draft 303(d) MethodsChanged to reflect current POR and our plan to incorporate accepted data from the 2018/2020 IR within the 2022 POR.
Assessments Specific to Flowing Surface Waters of the State and CanalsConventional Parameter Assessments45Response to CommentsStream grab samples are assessed against the instantaneous minimum, 7-day average, and 30-day average criteria. DWQ will assess against early life stage (ELS) criteria where ELS presence has been confirmed in a specific waterbody.
Assessments Specific to Flowing Surface Waters of the State and CanalsConventional Parameter Assessments45-50Draft 303(d) MethodsChanged the percent exceedance language. Now, we calculate a percent exceedance based on the number of samples (or averages) exceeding the criterion divided by the total number of samples. Details therein.
Assessments Specific to Flowing Surface Waters of the State and CanalsNutrient Assessments Specific to Headwater Streams50-54Draft 303(d) Methods; Response to CommentsNew method. Edited language from draft 303(d) methods to better reflect EPA approval letter and added the approved decision matrix to the text.
Assessments Specific to Flowing Surface Waters of the State and CanalsNarrative Standards: Biological Assessments55-59Response to CommentsUpdated links, removed sentence describing how other states use O/E.
Escherichia coli Assessment for All WatersData Preparation72-75Draft 303(d) MethodsChanged percent exceedance language in Scenario A to be consistent with conventional parameter assessments section.
Narrative Standards for All WatersHarmful Algal Blooms (HAB)79Draft 303(d) MethodsAssessments on hold.
Appendix 1Priority Parameters134-144Draft 303(d) MethodsAdded Headwater Numeric Nutrient Criteria parameters and noted the hold on HAB assessment parameters.
Appendix 6EPA Delisthing Codes158Draft 303(d) MethodsUpdated EPA Delisting Codes
Appendix 8Response to comments161Response to CommentsAdded comment/response matrices to methods.

Questions and Comments

Elise Hinman (
Integrated Report Coordinator
(385) 602-7277

Jodi Gardberg (
Watershed Protection Section Manager
(801) 536-4372