Presentation Transcript

1. Nutrient Criteria Development in Louisiana Water Quality Standards Section Water Permits Division Office of Environmental Services Louisiana Department of Environmental Quality December 2, 2010
2. OverviewNutrient Criteria Development Background LDEQ’s Plan to Develop Nutrient Criteria Evaluation of Approaches (EPA Guidance) LDEQ Data Collection Efforts (Inland Rivers and Streams) Data Summary (Inland Rivers & Streams) Other Issues and Studies
3. I. BackgroundLouisiana Water Quality Standards (WQS) Based on and authorized by Clean Water Act (CWA) Section 303(c) CWA Section 304 Requires EPA to develop criteria as guidance which Louisiana may use in adopting standards WQS are provisions of Louisiana State Law Authorized by Section 2074 B (1) of the Louisiana Water Control Law of the Environmental Quality Act (Louisiana Revised Statute, L.R.S. 30:2071-2078)
4. I. BackgroundRole of WQS in WQ Management Set and revise WQS for state waters Used to assess use attainment 305(b) Report Endpoint for: Total Maximum Daily Loads (TMDLs) Wasteload Allocations (WLAs) Load Allocations (LAs) Permit limits
5. I. BackgroundSuspected Causes of Impairment “Top” causes of impairment: Dissolved oxygen, fecal coliform and nutrients Nutrients: Nitrogen and Phosphorus DRAFT 2008 303(d) List Suspected Impairment in 10 Subsegments Suspected Sources of Impairment: Natural Conditions Natural Sources On-Site Treatment Systems Site Clearance (Land Development or Redevelopment) Residential Districts Forced Drainage Pumping Upstream Source Source Unknown
6. I. BackgroundNitrogen (N) and Phosphorus (P) Man-caused contributions to N and P Overuse of fertilizer (residential and agricultural) Rainfall flowing over cropland and pastures with no Best Management Practices (BMPs) Rainfall flowing over urban and suburban areas Wastewater treatment plants discharge Overflow from septic systems
7. II. LDEQ’s Plan for Nutrient Criteria Development EPA’s 304(a) Technical Guidance: Water Body Specific Rivers and Streams, Lakes and Reservoirs, Wetlands, and Estuaries Describes several criteria development methods Statistical and Relationships Recognizes an Ecoregional Framework Ecoregion = area of relative homogeniety in ecological characteristics “Reference” condition – “least-impacted”
8. II. LDEQ’s Plan for Nutrient Criteria Development States need a plan to: Develop the information set Assess reference condition for nutrients Develop criteria Determine how to apply numeric criteria State plans considered by EPA to be commitment on the States part to: Develop numeric nutrient criteria, and Adopt quantitative nutrient standards
9. II. LDEQ’s Plan for Nutrient Criteria Development LDEQ submitted 1st version of plan in December 2001 Continued working toward development of ecoregion-based numeric nutrient criteria for LA water bodies Submitted an updated and expanded version in December 2004 Accepted as ‘mutually agreed upon’ by EPA on June 20, 2006 http://www.deq.louisiana.gov/portal/tabid/69/Default.aspx
10. II. LDEQ’s Plan Ecoregional Approach
11. II. LDEQ’s Plan Water Body Types Freshwater Inland Rivers and Streams Inland Wetlands Lakes and Reservoirs Estuarine and Coastal Waters Brackish and Saline Wetlands Nearshore Gulf of Mexico Big Rivers and Floodplains Boundary Waters Sabine, Red, Ouachita, and Pearl Mississippi River and Atchafalaya River Basin
12. II. LDEQ PlanResearch in Louisiana Water Bodies
13. III. Evaluation of ApproachesSummary of EPA Guidance Methods EPA Level III Ecoregion Nutrient Criteria Recommendations based on 25th percentile of all streams in Louisiana Evaluate the 75th percentile of reference streams in Louisiana 35 65 74 75 34 73 75% 25% ReferenceStreams All Streams USEPA. 2000. Nutrient Criteria Technical Guidance: Rivers and Streams
14. III. Evaluation of ApproachesSummary of EPA Guidance Methods Frequency distribution of all streams in Louisiana for arbitrary determination of percentile breakpoints for least- and most-impacted streams USEPA. 2000. Nutrient Criteria Technical Guidance: Rivers and Streams
15. III. Evaluation of ApproachesSummary of EPA Guidance Methods Trophic state classification (eutrophic, mesotrophic, and oligotrophic) to define degree of plant material in a water body using percentiles and cluster analysis Empirical models (simple and multiple linear regression) to determine relationships between nutrients and algal biomass Impact of land use on in-stream nutrient concentrations Identify relationships between dissolved oxygen, nutrients, and chlorophyll a
16. III. Evaluation of ApproachesLane and Day (2008) Describe reference conditions for rivers and streams in four targeted inland ecoregions Use previously collected and recent data for nutrients, dissolved oxygen, and other parameters in identified water bodies Analyze data and approaches for evaluating nutrient conditions in the least-impacted reference streams Compare water quality, primary productivity, and the EPA recommended variables TN, TP, Chlorophyll a, Transparency
17. IV. LDEQ Data Collection Efforts Inland Rivers and Streams Historical data collection 1991 through 1996, 2 times in year (not monthly) Data gap analysis Data Inventory Recent data collection Monthly Oct 2008 through Oct 2009 Parameters measured: Continuous Monitoring Water Quality Canopy Cover Habitat Assessments Biological (Fish)
18. V. Data Summary for Inland Rivers and Streams Total Phosphorus (TP) Total Nitrogen (TN) Sum of Nitrate-Nitrite (NO3NO2) and Total Kjeldahl Nitrogen (TKN) Chlorophyll a (CHL A)
19. V. Data Summary Additional Considerations Seasonal Differences Drainage Area Small Medium Large
20. VI. Other Issues and Studies Regulatory Issues/Rulemaking Requirements Fiscal and Economic Impact Statements (FEIS) Required by L.R.S. 49: 953 for all rules (including WQS) whether or not there is a fiscal and economic impact Economic Cost/Benefit and Small Business Flexibility Act No. 820 of 2008 Regular Session Enacted R.S. 49:968.2-965.8 Requires state agencies to prepare an economic impact statement and a regulatory flexibility analysis prior to adoption of any proposed rule affecting small businesses Newer requirements not included in 2006 Nutrient Criteria Development Plan and may expand time necessary for promulgation process
21. VI. Other Issues and StudiesGulf of Mexico Alliance (GOMA)Action Plan II 2009-2014 Action 1: Characterize Nutrients and Nutrient Impacts to Coastal Ecosystems in the Gulf of Mexico Action 2: Coordinate Efforts to Support State Development of Nutrient Criteria for Gulf of Mexico Coastal Ecosystems Action 3: Increase Regional Coordination to Reduce Hypoxia in Gulf of Mexico Coastal Waters and Estuaries Action 4: Reduce Excess Nitrogen and Phosphorus Inputs to Gulf of Mexico Coastal Waters and Estuaries http://gulfofmexicoalliance.org
22. VI. Other Issues and StudiesCoastal Protection and Restoration FY 2011-2012 Expenditures exceed $1 Billion Protection Hurricane Buffers, Levees, etc. Restoration Wetlands, Diversion, etc. http://www.ocpr.louisiana.gov
23. Nutrient Criteria Development in Louisiana CONTACT INFORMATION Dugan Sabins (dugan.sabins@la.gov) Steph Braden (steph.braden@la.gov) Kristine Pintado (kris.pintado@la.gov) Amanda Vincent (amanda.vincent@la.gov) Water Quality Standards Section Water Permits Division Office of Environmental Services Louisiana Department of Environmental Quality