12/08/2020 - Laserfiche WebLink

Home Browse Search

Page 11 Attachment B: Supporting Research November 24, 2020 Update 2— Research Review Phase of IRL Plan Management Action Plans (BMAPs) are created, which act as blueprints for restoring impaired waters by requiring the reduction of pollutant loadings to meet the allowable loadings established in a TMDL. BMAPs represent a set of strategies designed to implement the pollutant reductions established in the TMDL. On June 27, 2018, FDEP adopted a Final Verified List of Impaired Waters forthe Group 5 Basins, which includes the County's portion of the Lagoon. Portions of the County's Lagoon are now listed as impaired for copper, iron, and fecal coliform bacteria (in addition to nitrogen and phosphorus). The Lagoon south of State Road 60 is considered impaired by copper (concentrations greater than 3 µg/L) and fecal coliform bacteria (concentrations exceed shellfish evaluation and assessment section thresholds). The Lagoon north of State Road 60 is considered impaired by iron (concentrations greater than 0.3 mg/L). Both of these sections are designated as Class 2 Waterbodies— Shellfish Propagation or Harvesting waters. TMDL allocations for these parameters have not yet been determined. The County falls within the Indian River Lagoon: Central Indian River Lagoon BMAP, initially adopted in February 2013, which implements TMDLs forthe regulation of TN and TP into the central portion of the Lagoon. This area covers approximately 476,469 acres that ultimately drain to the Lagoon. Principal sources of pollution were identified from agriculture, municipal separate storm sewer systems (MS4), point source facilities (like domestic and industrial wastewater facilities), and stormwater sources (like cities, towns, and water control districts). At the time the BMAP was implemented for the Central IRL, no assigned allocations were determined based on FDEP's evaluation. A two-step process was used to assess progress in the IRL Basin towards the median seagrass depth limit target. FDEP conducted this evaluation using seagrass data from 2003, 2005, 2006, 2007, and 2009. All project zones within the Central IRL were found to be compliant with their two-step evaluation process, meaning stakeholders in this area were not required to make additional reductions at the that time. The BMAP was initially anticipated to cover a five-year period but has not been updated since its adoption in 2013. Any projects completed during this time period were not considered requirements of the BMAP. The County completed various Lagoon improvement projects since 2013, even though it was not a regulatory requirement of them. Since the BMAP's creation, FDEP has been in communication with the County about their intentions to set new, updated BMAP allocations for the County to follow. This effort has especially picked up since early 2020, with FDEP's push forward of new allocations using a new modeling system. Updates are forthcoming on the amounts of nitrogen and phosphorus the County will be expected to remove from waters before they reach the Lagoon. The revised BMAP will have some changes from what was completed in previous BMAPs. In addition to the model being used to determine allocations being different from what was previously used, the BMAP boundaries have been modified to better match the specific model boundaries. The results produced from the model are supposed to take into account acreages and loading estimates, which will produce the reduction requirements for each entity involved in the BMAP area. FDEP has the authority to regulate these amounts and can enforce penalties if they are not met by each entity. The BMAP is further broken down into project zones, with the County falling into Project Zones B, SEB, and SIRL. In Project Zone B, as of the .most recent draft allocation numbers, the County has a required reduction of 165,800 lbs/yr of TN and 21,562 lbs/yr of TP. In Project Zone SEB, as of most recent draft allocation numbers, the County has a required reduction of 44,893 lbs/yr of TN and 112