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a � project is listed in the St. Johns River Water Management District Comprehensive 5 -Year Plan as a priority project for funding during year 2 , FY2000 (IRLCCMP, revised 1998) . ESTIMATED POLLUTANT LOAD REDUCTION: Construction drawings are approximately 80 percent complete and SJRWMD permit applications have been submitted. Changes to the design and permit may become necessary for the North Pond, if the property owner designates a different location for the stormwater facility. The goal is to achieve the maximum amount of pollutant reduction within the constraints of the previously developed area. There will be no increase in peak discharge rates for either the mean annual or the 25-year/24-hour storm events. PROJECT OBJECTIVES : In 1994, Woodward-Clyde, consultants under contract to the Indian River Lagoon National Estuary Program (IRLNEP), published eight volumes of technical reports describing the historical data reviewed, their assessment of the data and its reliability. The three reports considered pertinent to Indian River County are the following: Status and Trends Summary of the Lagoon, The Preliminary Water and Sediment Quality Assessment of the Indian River Lagoon, and Loadings Assessment of the Indian River Lagoon . In these volumes of literature, the Indian River County area of the Lagoon (from Sebastian Inlet to the St. Lucie County Inlet) is designated by Woodward-Clyde as Segment 3 . Segment 3 , known as the South Central Indian River Lagoon basin, is further divided into 24 sub-basins. Figure B indicates the area of the East Roseland project within Segment 3 . The major canal systems and large basins within Segment 3 that have been extended by ditching contribute the largest pollutant loadings in this segment. Three Chapter 298 districts exist within this basin. They are Fellsmere Farms Water Control District, Sebastian River Water Control District, and Indian River Farms Water Control District. These three districts are varied in land use and drainage characteristics. The highest loadings in the South Central Indian River Lagoon segment occur in the Indian River Farms Water Control District sub-basins, due to the characteristics of this urban built-out area, which utilizes extensive ditching, and canal systems draining to the Indian River Lagoon. When compared to other segments throughout the Indian River Lagoon region, it was calculated by Woodward-Clyde that Segment 4 (St. Lucie County area) accounts for the highest segment-wide pollutant loads, followed by Segment 3 , the Indian River County area. Woodward-Clyde noted that Indian River Farms Water Control District and Sebastian River Water Control District are among the highest area loading rates for the entire waterbody. Woodward-Clyde attributes these high loadings to the intense agricultural uses or the combinations of urban and agricultural development. Woodward-Clyde listed priority issues for the Lagoon as follows : ( 1 ) reduction of stormwater runoff loads from the urban areas; (2) the initiation of studies to determine if septic tanks are impacting the Lagoon by contributing fecal coliforms and excess nutrients; (3) the retrofitting of stormwater systems in developed urban areas, including US Highway 1 ; and (4) the use of best management practices (BMPs) in stormwater treatment. To conclude, in Segment 3 , the effects of the Sebastian River and the Indian River Farms Water Control District discharges are obvious, as salinity values drop to about 26.0 ppt near the Vero North, Main, and South Canal outfalls . This part of the Lagoon has a small surface area, so evaporation is reduced. Another example of the effect of the freshwater discharge into this segment is color. According to Woodward-Clyde, wet season color values are higher than dry season values by a factor of three, indicating discharge of colored, tannin-laden waters during wet season stormwater and groundwater flow. Total phosphorus values around the three Vero canal discharge points (South, Main and North canals), as well as at the Sebastian River, the Fellsmere Canal, and C-54, are substantially higher than elsewhere in the Lagoon. Total Kjeldahl Nitrogen is also elevated in the portion of the Lagoon between Wabasso and Vero Beach, indicating that this entire segment of the Lagoon is affected by discharges from the Sebastian River and the Indian River Farms Water Control District. Several technical objectives relating to the improvement of water quality for the East Roseland area include: ( 1 ) limit average discharge rates; (2) limit post-development peak discharge rates to pre-development peak levels; (3 ) provide approximately one-half inch detention for the watershed; and (4) reduce flood elevations by constructing stormwater runoff storage. Activities in the Indian River County ' s Surface Water Management Plan are expected to reduce solids, sediments, organic matter, freshwater and nutrients discharged from Indian River County' s stormwater systems. These actions will influence Lagoon trends in a positive direction. To date, Pollutant Load Reduction Goals DEP Agreement No. G0061 , Attachment A, Page 2 of 9