12/08/2020 - Laserfiche WebLink

Home Browse Search

Page 10 Attachment B: Supporting Research November 24, 2020 Update 2 — Research Review Phase of IRL Plan activities not contrary to the public interest. Other than federal and state rules and regulations, the County has several local ordinances that discuss or reference stormwater runoff: Title 11 — Taxes, Utilities and Special Districts: Chapter 200 — Municipal Service Taxing or Benefit Unit, Part III - Stormwater; Title 111 — Police Power Ordinances: Chapter 316 — Fertilizer and Land Management; Chapter 318 — Illicit Stormwater Discharge; Title IX — Land Development Regulations: Chapter 901— Definitions; Chapter 904 — Nonconformities; Chapter 910 — Concurrency Management System; Chapter 911— Zoning; Chapter 912 — Single Family Development; Chapter 913 — Subdivisions and Plats; Chapter 914 — Site Plan Review and Approval Procedures; Chapter 915 — Planned Development (P.D.) Process and Standards for Development; Chapter 917 — Accessory Uses and Structures; Chapter 926— Landscape and Buffer Regulations; Chapter 927 —Tree protection and Land Clearing; Chapter 928 - Wetlands and Deepwater Habitat Protection; Chapter 930 — Stormwater Management and Flood Protection; Chapter 931 - Wellfield and Aquifer Protection; Chapter 932 — Coastal Management; Chapter 934 — Excavation and Mining; Chapter 954 — Off -Street parking; and Chapter 971— Regulations for Specific Land Uses. Along with local County ordinances, a special permit is required if an ERP area requires discharge into the Indian River Farms Water Control District's canals. This permit is known as an "Application for Connection to or use of District Facilities" with required approval from IRFWCD. One of the major rules and regulations the County must adhere to in regard to protecting Lagoon water quality is FDEP's Total Maximum Daily Loads (TMDLs). Using information provided from years of studies conducted by SJRWMD, and in accordance with the CWA, FDEP determined that Lagoon waters within the County were impaired by nitrogen and phosphorus concentrations, which has resulted in decreased seagrass coverage in the Lagoon. As a result, a Secretarial Order added these waters to the Verified List of Impaired Waters for the Lagoon Basin on December 12, 2007. After an impaired water designation, a TMDL is established for each pollutant identified to reduce pollutant loadings with the hope of restoring the waterbody. A TMDL represents the maximum amount of a pollutant that a surface water can absorb and still meet the established water quality standards that protect human health and aquatic life. TMDLs for nutrients and dissolved oxygen for the Indian River Lagoon and Banana River Lagoon were adopted by FDEP in March 2009. Nutrient loading targets were established using a three -fold approach. First, regulators established the full -restoration target for seagrass coverage. This target, and nutrient targets, were based on segment -specific seagrass depth limits, and the relationship between seagrass depth limits and model -simulated Total Nitrogen (TN) and Total Phosphorus (TP) loadings. The median seagrass depth target was established at 1.2 meters —1.7 meters for the Central IRL segments. Second, regulators established the relationship between seagrass depth limit and TN and TP loadings from point and nonpoint sources. Finally, regulators established TN and TP targets based on a 10 percent deviation (shoreward) from the seagrass full -restoration targets and the relationship between seagrass depth limit and nutrient loadings. Based on these test runs, lagoon -wide TN target loading was established at 3.34 lbs/ac/yr and TP target loading was established at 0.546 lbs/ac/yr. Central IRL TN target loading was established at 2.90 lbs/ac/yr and TP target loading was established at 0.574 lbs/ac/yr. According to 62- 304.520(8) Florida Administrative Code (F.A.C.), the Central and southern South Lagoon was defined to have TMDLs of 278,273 lbs/year of TN and 53,599 lbs/year of TP. After a TMDL is established, Basin 111