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Some Context behind the Implementation of Numeric Nutrient Criteria or Why do we have these Water Quality Regulations?. Mark W. Clark and Thomas Obreza Soil and Water Science Department University of Florida, Gainesville April 20, 2012. Overview. Federal Clean Water Act
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Some Context behind the Implementation of Numeric Nutrient Criteria or Why do we have these Water Quality Regulations? Mark W. Clark and Thomas Obreza Soil and Water Science Department University of Florida, Gainesville April 20, 2012
Overview • Federal Clean Water Act • State Designated Uses • Protective Criteria • Implications of Impairment
Clean Water Act 1972 • As part of the Federal Clean Water Act 1972, USEPA requested states develop: • Designated uses for waters of the state (lakes, reservoirs, rivers, streams, estuaries and wetlands), • Criteria that would protect designated uses, • Corrective process that would be implemented if a designated use was not being met (i.e. if the waterbody was determine to be “impaired”)
Designated Uses for Florida Waterbodies • Class I – Potable Water Supplies • Class II – Shellfish Propagation or Harvesting • Class III – Recreation, Propagation and Maintenance of a Healthy, Well-Balanced Population of Fish and Wildlife • Class III-Limited – Fish Consumption; Recreation or Limited Recreation; and/or Propagation and Maintenance of a Limited Population of Fish and Wildlife • Class IV – Agricultural Water Supplies • Class V – Navigation, Utility and Industrial Use F.A.C. Chapter 62-302 Surface Water Quality Standards http://www.dep.state.fl.us/legal/rules/shared/62-302.pdf
Approaches to Protect Designated Use • Criteria • A standard, rule, or test on which a judgment or decision can be based • Concentration or measurement that is protective of the intended uses of the water • Types of Criteria: • Numeric • Narrative
Example of Numeric Criteria Dissolved Oxygen Criteria (Current) • Class I • Shall not be less than 5.0. • Class II • Shall not average less than 5.0 in a 24-hr periodand shall never be less than 4.0. • Class III • Fresh-Shall not be less than 5.0. • Marine-Shall not average less than 5.0 in a 24-hr period and shall never be less than 4.0. • Class IV • Shall not average less than 4.0 in a 24-hr periodand shall never be less than 3.0.
Example of “Narrative” Nutrient Standard • Rule 2-302.530 FAC • “in no case shall nutrient concentrations of a body of water be altered so as to cause an imbalance in natural populations of flora or fauna”
Assessment and Reporting of State Water Quality • Continuous monitoring of state waters • Biannual reporting of state water quality referenced against standards for specific designated use. • 305(b) list sent to USEPA indicating those water bodies that “potentially do not attain” designated use.
Motivation for “Numeric” Criteria - National Water Quality Assessment • The National Water Quality Inventory (1996 report to congress) cites nutrients (nitrogen and phosphorus) as one of the leading causes of water quality impairment in our Nation's rivers, lakes and estuaries. • 40%of the rivers were impaired due to nutrient enrichment; • 51% percent of the surveyed lakes, and • 57% of the surveyed estuaries were similarly adversely affected. • Nutrients have also been implicated with both the large hypoxic zone in the Gulf of Mexico, hypoxia observed in several East Coast States, and Pfiesteria-induced fish kills and human health problems in the coastal waters of several East Coast and Gulf States.
EPA’s National Strategy for the Development of Regional Nutrient Criteria • In 1998 EPA rolled out the National Strategy for Development of Regional Nutrient Criteria to encourage all states and tribes to adopt numeric nutrient water quality criteria. • 2002 FDEP and EPA agreed on plan to establish numeric nutrient criteria. • Between 2002 and 2009 FDEP spent over 20 million dollars developing numeric criteria.
Quality of State Waters Florida Water Quality Assessment 2002 305(b) report
Estuary Impacts Florida Water Quality Assessment 2002 305(b) report
Lake Impacts Florida Water Quality Assessment 2002 305(b) report
Stream Impacts Florida Water Quality Assessment 2002 305(b) report
Quality of Florida Waters 2010 • 1,9180 miles of rivers and streams (8%) • 378,435 acres of lakes (26%) 2010 Integrated Water Quality Assessment for Florida Report Nutrients were the first and second reason for listing lakes and estuaries as impaired (based on narrative standard) and the fourth reason for listing streams (after Dissolved Oxygen, mercury and fecal coliform) • 549 nutrient related TMDL’s
Lawsuit from Earthjustice • On behalf of several environmental organizations of Florida, a suit in July 2008 claimed that: • There was an unacceptable delay by the federal government to set limits for nutrient pollution. • Claimed that EPA had previously determined the need for numeric criteria under the CWA. • Argued that EPA was obligated to promptly propose criteria for Florida.
Timeline of EPA NNC Implementation in Florida • January 26, 2010 • EPA published Proposed “Water Quality Standards for the State of Florida’s Lakes and Flowing Waters” (75 FR 4173). • EPA conducted 13 public hearing sessions in six cities in Florida and held a 90-day public comment period following publication of the proposed rule. • 22,000 public comments on the proposed rule
EPA Final Rule • November 14, 2010 • EPA Administrator signed Final “Water Quality Standards for the State of Florida’s Lakes and Flowing Waters.” (did not include S. Florida flowing waters) • February 4, 2011 • Implementation of Site-Specific Alternative Criteria (SSAC) provision • March 6, 2012 • Initial Implementation date of final rule extended for 15 months to allow cities, towns, businesses and other stakeholders as well as the State of Florida a full opportunity to review the standards and develop flexible strategies for implementation. • March 5, 2012 • EPA promulgated an extension of the effective date of this rule by 4 months to July 6, 2012
Florida’s Alternative Rule • April 22, 2011 • FDEP asked EPA to withdraw the determination. EPA did not approve or deny request, June 13, 2011 • November 10, 2011 • FDEP proposes alternative rule • December 8, 2011 • Alternative rule approved by Florida Environmental Regulation Commission (Adoption of Nutrient Standards)
Florida’s Alternative Criteria Passed into Law • December 9, 2012 • FDEP submits amendments to chapters 62-302 and 62-303, F.A.C. (numeric nutrient standards) • January 24, 2012 • Florida House approves amendments • February 10, 2012 • Florida Senate approves amendments • February 16, 2012 • Governor signs Water Quality Criteria into law • Pending EPA approval
Is this the end? • That was just for inland waters north of Lake Okechobee • Rule for estuaries, coastal waters and flowing waters in the South Florida Region is currently due to be proposed by EPA May 21, 2012. • Rule for wetlands has not even been discussed.
Some Pro’s and Con’s of Narrative vs Numeric Criteria • Narrative criteria • Pro’s • Allows for site specific interpretation • Con’s • Waterbody is already impaired by the time narrative criteria of impairment is met • Threshold of impairment is somewhat subjective • Numeric Criteria • Pro’s • Threshold of impairment is a “bright line” • Makes establishing TMDL easier if impairment occurs • Con’s • Initial criteria determination is rarely site specific and prone to under or over protection of waterbody.
New Numeric Nutrient Criteria • New criteria will not automatically restrict the use of fertilizer. • New criteria will not change the designated use of a water body. • New criteria will establish a “brighter line” to evaluate potential nutrient impacts to state waters. • New criteria will likely be used to establish discharge permit levels for point sources. • New criteria will increase the number of water bodies listed as impaired
Impaired Waterbody • What if a water body does not meet protective criteria – i.e. “potentially does not attain designated use”? • Section 303(d) of the Clean Water Act (CWA) requires states to submit lists of surface waters that do not meet applicable water quality standards (impaired waters) • The Florida Watershed Restoration Act (1999) clarified FDEP’s authority for the TMDL program and directed the Department to develop a methodology, to implement.
How do you know if you are in a TMDL watershed? http://www.dep.state.fl.us/water/tmdl/index.htm
FDEP’s Watershed Management Approach - Five Phase Cycle • Phase 1: Watershed Evaluation, evaluate status of the quality of surface water and groundwater to identify potentially impaired waters for which TMDL’s may be needed. • Phase 2: Strategic Monitoring, verification of listing as impaired and to collect data for TMDL development • Phase 3: Developing and Adopting TMDL’s, prioritization of impaired waters then development and adoption of TMDL for basin. • Phase 4: Developing Watershed Management Plans, plan specifying how pollutant loadings from point and nonpoint sources of pollution will be allocated and reduced in order to meet TMDL requirements. (BMAP) • Phase 5: Implementing Watershed Management Plans, implementation of Phase 4
What if a Waterbody is Verified Impaired? • Determine source of Impairment low dissolved oxygen level excessive algae growth excess nutrient load • Determine threshold concentration or load of pollutant that will still maintain waterbody designated use (assimilative capacity or Total Maximum Daily Load) • Determine existing load to waterbody
Example relationship between limiting nutrient (P)and chlorophyll-a Mean TP vs. Algal blooms over 40ug/L (Walker and Havens 1995)
Determine Nutrient Budget Atmospheric Inputs How much can be added and still maintain target water column concentration? Surface Inputs Water Column target concentration (100 ppb) Surface Outflows 40 ppb Internal Loading (recycling) System Uptake (assimilation) How much is presently being added? Sediment
TMDL includes a Margin of Safety • A margin of safety (MOS) is required as part of a TMDL in recognition that there are many uncertainties in scientific and technical understanding of the chemical and biological processes that occur. • The MOS is intended to account for such uncertainties in a conservative manner that protects the environment. • According to EPA’s guidance, a MOS can be achieved through reserving a portion of the load for the future, or using conservative assumptions in calculating the load. • TMDL = ∑Point Sources + ∑Nonpoint Sources + Margin of Safety
Nutrient Load Reduction • TMDL is the assimilative capacity of a watershed and waterbody while still protecting the designated use. • The Difference between actual loading and TMDL is the load that needs to be reduced. • Load reduction required needs to be allocated among stakeholders.
Basin Management Action Plan • A Basin Management Action Plan (BMAP) is the primary tool to go about implementing the Total Maximum Daily Load (TMDL) • The process for BMAP development involves collaboration among local stakeholders and FDEP staff. • Once consensus among stakeholders over the BMAP has been achieved, it is adopted by Secretarial Order and enforced.
Recommended Guidelines for TMDL Allocations • FDEP Formed Allocation Technical Advisory Committee (ATAC) • First step to achieve equity was to “level the playing field” in treatment effort between point and nonpoint sources. Point source are already required to provide, at a minimum, technology based treatment levels. • ATAC felt nonpoint sources should be expected to provide comparable minimum levels of treatment, before additional reductions were expected of point sources. • The ATAC subsequently decided that the comparable minimum treatment for nonpoint sources should be the Best Management Practice (BMPs) developed and adopted for that activity.
TMDL Allocation Example Maximum load allowed (TMDL) Allocation process address this excess load
Step 1 • Calculate the amount of pollutant reductions that would be achieved if: • a) 45% of all agricultural and silviculture operations in the basin and in upstream watersheds implemented the appropriate BMPs • b) 45% ofurban areas met stormwater treatment requirements for new development, and • c) 45% of the homes with septic tanks within the 100-year floodplain were hooked up to a regional sewer system.
Effect of Step 1 Reductions 40,000 pounds short
Step 2 • If step 1 was not sufficient to meet the TMDL, then calculate if • a) 90% of all agricultural and silviculture operations in the basin implemented the BMPs, • b) 90% ofurban areas met stormwater treatment requirements for new development, and • c) 90% of the homes with septic tanks within the 100-year floodplain were hooked up to a regional sewer system.
Effect of Step 2 Reduction 22,000 pounds short
Step 3 • If the reductions for step 2 are not sufficient to meet the TMDL, the third recommended step is to allocate reductions to all sources except those where loading is at background levels or those that have provided treatment beyond BAT levels, in increments of 10% until the TMDL is met.
Effect of Step 3 Reductions Step 1 10,000 lbs Step 2 28,000 lbs Step 3 15,000 lbs 53,000 lbs Only need an 8% reduction in step 3, not 10 % reduction to meet TMDL target
Iterative Process • Continuous monitoring required to determine progress toward TMDL target • Use attainability is evaluated biannually • Revisit TMDL target if use attainment is not met • Change TMDL or allocation if necessary • Efficacy of BMPs may be revised with more data which may require reassessment of load allocation
How Does this Relate to GIBMP’s? • These Policies are the underlying driver to regulate water quality in the State of Florida • Ultimate goal is not to create condition of impairment that results in triggering TMDL/BMAP process. • Implementation of GI BMPs will reducing the likelihood of triggering impairment condition. • GI BMP’s provide tools that reduce loads in TMDL watersheds and are part of urban BMAP load reduction strategy.