Providing Reasonable Assurance to Prevent TMDLS: The Tampa Bay Experience

In a region that has experienced population growth rates in excess of 20% from 19942000 and with over 110,000 registered pleasure boats, it is imperative that aggressive management strategies be implemented to preserve and protect Tampa Bay's delicate natural resources. Starting in the 1950's, with uncontrolled development along the bay's shoreline, local bay stewards observed deteriorated water quality along with the decline in natural resources such as fisheries and wildlife and the disappearance of critical habitats like seagrass and wetlands. This decline continued for decades until the passage of environmental regulations in the 1970's, which aided in curbing this negative trend. Since this time, local communities and industry have made great strides in improving water quality and assisting in the recovery of this damaged ecosystem. The current challenge for bay stewards is to maintain the improved water quality gains, while providing additional protection brought on by the pressures of the continuing growth of the region. Programs and policies established by the local communities and elected officials have been established to ensure adequate oversight and evaluation of the Bay's resources. The establishment of the Tampa Bay National Estuary Program (TBNEP) in 1991 was paramount in coordinating the activities of the local communities and industries. Management policies were coordinated by local elected officials, while bay resource evaluations were conducted by local, state, and regional technical scientists. These combined efforts aided in the establishment of resource-based goals for the bay, along with interim targets and adaptive management strategies. As part of the Comprehensive Conservation Management Plan for Tampa Bay, a resource goal establishing seagrass coverage that was observed in 1950 (less areas that were permanently altered) was adopted. This goal required the protection of 24,840 acres of existing seagrass bed, along with the restoration of 13,160 additional acres. This was to be accomplished by ensuring that adequate light reached to an area-specific depth of 1.0 to 2.5 meters in regions that historically supported seagrass. A key factor controlling light attenuation in bay waters was algae growth supported by nutrient inputs, especially nitrogen. A paradigm was established that linked nitrogen loads to chlorophyll a concentrations observed in the bay. By limiting nitrogen loads, water quality improvements were expected. The Policy Board adopted an annual average nitrogen load to the bay of 3,800 tons (based on average annual load for the period 1992-1994). The corresponding average annual chlorophyll a target for the major bay segments with the adopted load is as follows: 8.5 u g/l for Old Tampa Bay, 13.2 u g/l for Hillsborough Bay, 7.4 u g/l for Middle Tampa Bay, and 4.6 u g/l for Lower Tampa Bay. To calculate and monitor nitrogen load reductions to the bay, each stakeholder developed an agency action plan describing projects along the bay and within the watersheds that reduced nitrogen loads to the bay. Additionally, the Nitrogen Management Consortium was created to coordinate nitrogen reduction activities between local governments, agricultural interests and regional industries. The Consortium annually monitors the progress towards meeting water quality targets. Adaptive management strategies are evaluated and implemented if necessary. Recently, there has been national interest in identifying and implementing management strategies for impaired surface waters to meet Total Maximum Daily Loads (TMDLs). A concern of local stakeholders was how to coordinate the adopted management plans for Tampa Bay with the need to meet the ever evolving impaired waters regulations. In 2002, the State of Florida adopted its impaired waters regulation, Chapter 62-303, Florida Administrative Code. This regulation stated in Section 62-303.100(5), that "impaired waters shall not be listed on the verified list if reasonable assurance is provided that, as a result of existing or proposed technology-based effluent limitations and other pollution control programs under local, state, or federal authority they will attain water quality standards in the future and reasonable progress towards attainment of water quality standards will be made...". In 2002, Tampa Bay Estuary Program (TBEP, formerly known as TBNEP) submitted reasonable assurance documentation, based on the locally adopted natural resources management strategies, to the Florida Department of Environmental Protection (FDEP) for consideration. FDEP found that the nutrient management strategies developed for Tampa Bay were consistent with the regulation and granted reasonable assurance status. The FDEP approval is contingent on TBEP continuing to monitor, evaluate and adjust management strategies as necessary. A full assessment report is required to be submitted to the State prior to the next impaired waters assessment cycle, or every five (5) years. The development of a resource base goal for Tampa Bay was both challenging and innovative. This presentation will describe the processes used by TBEP; how to establish key components (such as a Nitrogen Management Consortium to implement the management strategy and a Decision Matrix to monitor progress towards targets); and, reporting criteria to ensure that both local management goals and TMDL requirements are achieved.