1 / 40

Indiana’s Draft 2010 303(d) List of Impaired Waters

Indiana’s Draft 2010 303(d) List of Impaired Waters. Jody Arthur Integrated Report Coordinator Office of Water Quality, IDEM. Clean Water Act Sections 305(b) and 303(d) . 305(b) requires states to make water quality assessments and provide water quality reports to U.S. EPA

colby
Download Presentation

Indiana’s Draft 2010 303(d) List of Impaired Waters

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Indiana’s Draft 2010 303(d) List of Impaired Waters Jody ArthurIntegrated Report Coordinator Office of Water Quality, IDEM

  2. Clean Water Act Sections 305(b) and 303(d) 305(b) requires states to make water quality assessments and provide water quality reports to U.S. EPA 303(d) requires states to submit a list of impaired waters to U.S. EPA Both now combined into one report submitted to U.S. EPA every two years Indiana Integrated Water Monitoring and Assessment Report

  3. IDEM’s Five-Year Basin Rotation • Monitoring • 305(b) Assessment • Integrated Reporting • 303(d) Listing

  4. The Integrated Report A comprehensive report of water quality conditions throughout Indiana Includes: Basin-scale assessments Reach-specific assessments on streams Lakes assessments Consolidated List contains reach-specific information for every lake and stream in IDEM’s Assessment Database

  5. Assessments at Two Scales Reach-Specific Assessments Comprehensive Assessments • Apply only to the reach sampled • Results compared to Water Quality Standards • Data from randomly selected sampling sites (probabilistic) + sites selected for a specific reason (targeted) • All designated uses • Apply to an entire basin • Results derived from statistical calculations • Data from sampling sites selected randomly throughout Indiana (probabilistic monitoring) • Aquatic Life Use and Recreational Use

  6. Example of Reach-Specific Assessment Results for Aquatic Life Use Support Provides assessment information for specific locations

  7. Example of Comprehensive Assessment Results for Aquatic Life Use Support

  8. Comprehensive Assessment • Allows Indiana to meet the CWA Section 305(b) goal of assessing “all waters of the state” • Overall trends in water quality • Also allows basin to basin comparison • Statistically robust with known level of confidence • Can predict water quality conditions for the basin • Does not indicate where specific impairments are located or the reasons for impairment • Probabilistic monitoring • Data can also be used to make reach-specific assessments • Resource intensive leaving comparatively few resources for follow-up

  9. Reach-Specific Assessments • Allow Indiana to meet the CWA Section 303(d) goal of identifying impairments that require Total Maximum Daily Loads (TMDLs) • Useful for watershed planning and restoration activities on local level • Can be used to determine if improvements have occurred (measures of success) • Applicable only to specific waters • Can’t extrapolate the results to other waters in the basin unless sampling data are directly representative • Incomplete picture

  10. IDEM’s Reach-Specific Water Quality Assessments Designated uses IDEM assesses Recreational Use (RECR) Aquatic Life Use (ALUS) Drinking Water Use Other Assessments Fish Tissue Lake Trends and Trophic State

  11. IR Categories in IDEM’s Consolidated List All waters in Assessment Database assigned an assessment unit (AU) Each AU placed in one category of the Consolidated List for each of its designated uses 303(d) list is a subset of the Consolidated List (Categories 5A+5B) AUs listed once for each impairment Draft 303(d) list builds on the previously approved list Finalized prior to submission to U.S. EPA

  12. IR Categories in IDEM’s Consolidated List Category 1  All designated uses have been assessed and are fully supported Category 2  The use has been assessed is fully supported and no other uses are impaired Category 3  Insufficient data and information to determine if the use is supported Category 4  The use is impaired but no TMDL required Category 5  The use is impaired and a TMDL is required

  13. 303(d) List Development Data are compiled and assessments made based on IDEM’s Consolidated Assessment and Listing Methodology (CALM) Assessment decisions entered into Assessment Database Assessment database queried for all assessments to date Each assessment unit placed in appropriate Integrated Report category for each designated use in accordance with IDEM’s CALM 303(d) list  Categories 5A and 5B (a subset of IDEM’s Consolidated List)

  14. U.S. EPA Delisting Rules New data indicates that Water Quality Standards are now being met Assessment and/or listing methodology changed and AU no longer considered impaired Original listing found to be in error A program other than TMDL is better suited to address the problem The problem is not caused by a pollutant TMDL is approved

  15. The Assessment Part of IDEM’s CALM Describes IDEM’s water quality assessment criteria and how they are applied No major changes to methodology for 2010 Added clarification Resegmentation Data minimums required for assessment Use of Tier I and Tier II criteria in assessments Use of site-specific criteria in assessments

  16. Resegmentation IDEM is Redefining AU in IDEM’s Reach Index, Assessment Database Originally developed in 2002 based on National Hydrography Database (NHD) Generally, all streams in a watershed assigned a single AU Prevented accurate application of assessment data IDEM is now revising its reach index Breaking large AUs into smaller, more representative units for assessment NHD now available in higher resolution, allows us to incorporate smaller reaches that didn’t show up on the map when original index was developed

  17. Resegmentation Resegmentation splits one AU into two or more smaller AUs Previous assessment information must be reevaluated to determine applicability to each new AU Any impairments are carried over to all new AUs until reassessment can be completed Short term effect  growth in number of listings Eventually, many will likely be removed once the data are reevaluated

  18. ALUS RECR Example Resegmentation All streams in watershed assigned a single AUID • RECR assessment applies to entire watershed • ALUS assessment applies only to one tributary system • Cannot correctly characterize extent of ALUS impairment in the Assessment Database

  19. RECR ALUS Example Resegmentation Original AU resegmented; data reevaluated for new AUs • RECR assessment can still be applied to each new AU • ALUS assessment can now be applied to the stream on which sample was collected • Extent of impairment can now be correctly characterized

  20. Use of Tier I & Tier II Criteria in Assessments Numeric criteria developed in accordance with methods provided in Indiana’s Water Quality Standard Usually developed to facilitate permitting Tier I meet all data requirements necessary to be incorporated into Water Quality Standard Tier II calculated with a smaller data set  typically more stringent Both applicable for CWA assessments

  21. Use of Site-Specific Criteria (SSC) in Assessments Usually developed to facilitate permitting SSC supersede other criteria but only for the specific substance in question In most cases, SSC are applicable only to reach(es) for which they were developed Resegmentation is often required in order to accurately apply SSC Usually complex Done on a case-by-case basis

  22. Grand Calumet River Resegmentation Initiated to facilitate permitting Necessary because AU originally defined in 2002 for the headwaters of the Grand Calumet River do not accurately reflect complexities of the system Several outfalls in downstream reaches significantly alter hydrology along the reach SSC for Cn applicable only to a one-mile reach within the original AU

  23. Grand Calumet RiverResegmentation INC0122_00 (headwater reach) was the only AU resegmented Split into three more representative AUs Remaining Grand Calumet River reaches downstream assigned new AUIDs and AU names to ensure continuity along entire river

  24. GCR Reassessment

  25. Grand Calumet River Reassessment Reassessed only for cyanide and ammonia All other previously identified impairments carried over to new AUs Reassessment based on original data and more recent data collected by IDEM in 2009

  26. 2009 Sampling by IDEM Known sources of Cn and NH3 upstream Existing fixed stations not sufficient to accurately characterize water quality conditions along newly defined AUs Monthly sampling from March – June, 2009 at two additional locations Additional data needed to determine if dilution from noncontact cooling water was indeed having a mitigating effect on upstream sources of Cn and NH3

  27. Effect of Grand Calumet River resegmentation on 303(d) List Apparent increase in Grand Calumet River listings not a function of water quality degradation Increase is result of resegmentation Impairments on original, single AU now applied to three

  28. Waterbodies added to Category 4A for completed TMDLs

  29. Waterbodies removed from Category 5 for one/more impairments based on new assessments and QAQC

  30. Waterbodies added to Category 5 for one/more impairments based on new assessments and QAQC

  31. Removed Added Back Resegmentations

  32. Indiana’s Draft 2010 303(d) List: Delistings

  33. Indiana’s Draft 2010 303(d) List: Additions

  34. Indiana’s Draft 2010 303(d) List

  35. Indiana’s Draft 2010 303(d) List

  36. Public Comment Period October 28, 2009 – January 26, 2010 IDEM welcomes your comments regarding the 2010 Draft 303(d) List of Impaired Waters

  37. www.idem.IN.gov/4680.htm Contact: Jody Arthur, Integrated Report Coordinator Office of Water Quality, IDEM 317-234-1424 jarthur@idem.IN.gov Where to Find More Information

More Related