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Land Use Acres % Rangeland 3255.75 15.00 Citrus 8682.00 40.00 Improved Pasture 1085.25 5.00 Miscellaneous (Urban) 8682.00 40.00 Land Use Totals (Acreage and %) 21705.00 100.00 POLLUTION REDUCTION STRATEGY: The Indian River Farms Water Control District (IRFWCD) in Indian River County, Florida is an area over 53,000 acres that is drained by an extensive network of poorly managed man-made canals. The IRFWCD discharges into the Indian River Lagoon, an Estuary of National Significance and a St. Johns River Water Management District (SJRWMD) Surface Water Improvement and Management (SWIM) program priority water body. In the East Indian River County Master Stormwater Management Plan (Master Plan), a pollutant loading analysis showed that the three discharge canals of the IFRWCD convey large amounts of suspended solids, nutrients, and floating vegetative debris into the lagoon, seriously degrading estuarine habitat. The canals also transport tremendous quantities of human -generated trash (Styrofoam cups, plastic, bottles, etc.) into the Lagoon. Treatment alternatives were investigated in the Master Plan. It was recommended that sediment and floating debris collection systems be used to effect a significant reduction in muck contributing solids, nutrients, floatables and trash into the Lagoon. This project is included as Alternative No. 4 in the "East Indian River County Master Stormwater Management Plan," pages 114-118, inclusive, and pages 207-213 capital improvements discussion. This project is specifically listed as a High Priority Level under Capital Project Prioritization on page 210. In the Master Plan, best management practices (BMPs) were investigated for the potential to improve the water quality of the three discharges of the IRFWCD canals. Several of these BMPs were determined to be well-suited for placement within the limited space available in the existing canal rights-of-way. The two general types of improvements which appeared to be effective given the existing conditions were floating debris capture systems and structural pollution control devices. The need for this project is described in the November 1996 'Indian River Lagoon Comprehensive Conservation and Management Plan" under the Water and Sediment Quality Improvement section. Recommendations for large drainage systems, such as the IRFWCD, are found in Action FSD-12, Freshwater and Stormwater Discharges Action Plan. The 2002 IRL SWIM Plan Update discusses the IRFWCD and the need to reduce TSS and nutrients in Chapter 5, page 133. A major concern stated in the SWIM Plan is the total phosphorus loading from the IRFWCD being higher than that from the Turkey Creek basin which is 1.5 times larger in area. Methods to treat or control pollution from stormwater runoff (BMPs) have traditionally included practices that are typically land intensive (dry retention areas, wet detention ponds) and have low maintenance requirements. However, as land has become scarcer and more valuable in Florida, efforts have also been focused on treatment technologies that are not as land intensive. Many of the more compact systems are adaptations of domestic and industrial wastewater treatment components. These active systems, which often include electrical or mechanical components, have come to be known as "structural" pollution control devices (PCDs). They have a higher operation and maintenance requirement than passive systems. Vortex collection devices force a circular flow of runoff within the structure, creating a vortex to improve the capture of suspended solids. Three manufacturers of these types of units are CDS Technologies, Inc. (CDS), Vortechnics, Inc. and H.I.L.Technology, Inc. (HIL). These are all patented technologies which use water pressure to force the water into the structure in a circular motion. The circular motion of the water and the momentum in the particles cause the suspended solids to be removed from the flow. The suspended solids continue to work downward and eventually are deposited into the bottom of the structure. The CDS system has been used successfully in many applications in Florida as well as other locations around the country. The CDS system uses a screen to directly capture all particles larger than 2400 microns. In addition, the vortex action results in the capture of some suspended material smaller than 2400 microns, as small as 600 microns. Testing of CDS equipment indicates that most gross pollutants will be captured, including the coarse and medium sands (approximately 80% of the content of most runoff flows). For the typical pre -cast design, the material collected is stored in the bottom of DEP Agreement No. G0182, Attachment A, Page 2 of 10