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Draft Indian River County Lagoon Management Plan Outline April 2019 limits to annual nitrogen and phosphorus loading, and seagrass losses were determined based on review of a composite of seagrass maps from 1943 to 1999. The establishment of TMDLs required the initiation of the basin management action plan (BMAP) process, which establishes enforceable, more detailed load allocations for impaired waterbodies. Point source dastewater facilities with National Pollution Discharge Elimination System permits were assigned a wasteload allocation in the TMDL, which are included in each facility permit. The stormwater sources, including permitted municipal separate storm sewer systems, other urban nonpoint sources, and agricultural stormwater, were assigne allocations through the BMAP process. However, based on the recovery of seagrasses through 2009, the lat t available aerial mapping data at the time of the BMAP analysis, the Central IRL stormwater entities did not re ive nutrient load allocations. The Central IRL BMAP was adopted by DEP in early 2013. As this first iteration of a BMAP process was ending, the "superbloom" of 2011 occurred. This HAB plagued the North IRL and Bana ' - River Lagoon, and a secondary bloom affected the Central IRL. Green alga, brown tide Aureoumbra lagu' -nsis, and picocyanobacteria each contributed to the blooms; however, the damage to seagrasses from these gal blooms would not be understood for several years. Since this "superbloom," blooms of picocyanobacteria, which are capa e of fixing nitrogen from the atmosphere, and dinoflagellates and Aureoumbra lagunensis, which are limited by itrogen in the water column, have created a new normal of nutrient and carbon cycling that leave the lagoon )n - constant state of alarm for HABs. Seagrass data in the lagoon showed a steady decline in 2011 compared to e 2009 survey. Seagrass made a small gain in 2013 and 2015 in the Central IRL, but the latest seagrass data rom 2017 again showed significant losses in the Central IRL. DEP is in the process of reevaluating the BMA for the Central IRL, and because of the seagrass losses that have occurred in the Central IRL since the BMA was adopted, load allocations for total nitrogen (TN) and total phosphorus (TP) will be allocated to the stekeholers in this area, including Indian River County. 1.3 PLAN ORGANIZATION The plan is organized into the following sections. Section 2.0 summarizes the plan goals and measurable goals to Revitalize the IRL. Thes in accordance with the TMDLs and BMAP, b within the IRL as a result of eutrophicatio Revitalize and repair damage to bent established to measure the progress actions. For the first phase of the pl and more general. For the secon specific, scientifically based, and Section 3.0 describes the cur and Stormwater Divisions, projects using natural pr historical cultural resou protect the IRL./ o jectives. This plan seeks to identify reasonable objectives and goals include regulatory requirements for nutrient load allocations, t also go further to evaluate the legacy loads and ecological damage and other aspects of human interaction. This plan seeks options to c communities such as seagrasses, oysters, and clams. Metrics are f lagoon Revitalization, and measurable goals are identified for lagoon , which includes identifying the Research needs, the objectives are broader phase of the plan, anticipated to be updated after three to five years, more uantified goals will be established to Revitalize the IRL. nt projects. Parks' Conservation Lands Division, Public Works' Coastal Engineering d the Utilities Department have combined forces to complete unique and innovative cesses. These projects Reduce nutrients entering the IRL, Revitalize natural and es, and provide access to the lagoon to educate the public and Rally the community to Section 4.0 identi -s prospective projects. This plan Researches the current and historical resources of the IRL and Responds the changing conditions of the IRL. Projects were selected in each category to Reduce nutrients, minimize lag t. e in lagoon response, Reduce risk, Revitalize natural lagoon resources, and optimize the return on investme Section 5.0 describes Indian River County's education and outreach efforts. Education and outreach are an important and cost-effective approach to Revitalize the IRL because these efforts allow the public to understand why the County is implementing projects to improve conditions and create a sense of responsible stewardship with TETRA TECH 3