1999-277 - Laserfiche WebLink

Home Browse Search

4D Contract #SD609AA EXHIBIT "A" —SCOPE, OF WORK VERO LAKES ESTATES STORMWATER 3YSTE4I RETROFIT I. IN'T'RODUCTION & BACKGROUND: The proposed project includes modifying u series of existing upland ponds for stormwater detention and water quality treatment for a 3,871 -acre watershed, located a utile south of the south prong of the St. Sebastian River, an area of special concern within the Indian River Lagoon, a state priority water body designated under the Surface Water Improvement & Management Program (SWIM) and part of the state's Unified Watershed Assessment. Thu project site, Vero Lakes Estates is located south of County Road 512, east of Interstate Highway 95, and west of the City of Sebastian in Indian River County (COUNTY).. The residential subdivision was platted between 1956 and 1960 and presently consists of a series of dirt roads with lot sixes ranging from 0.25 acres to I acre. The majority of lots within the 3,871 -acre drainage basin are presently undeveloped. The existing drainage system consists of front and back lot swales which drain north/south directly to three main collector ditches, known as Canals A, B and C. These three ditches serve the 2.410 -acre Vero Lakes Estates drainage area as well as 1,461 acres of off site area which drain to the ditches. Canals A. B and C drain from west to east to a discharge point in the Sebastian River Water Control District Lateral D Canal which eventually drains to the South Fork of the Sebastian River and to alae Indian River Lagoon. In the existing condition, the subdivision has marginal capacity for stormwater treatment due to the large drainage area and relatively small drainage swales and ditches. The vast majority of this 3,871 -acre northern COUNTY watershed drains eastward to the Indian River Lagoon (IRL). This project will help to improve the water quality in the St. Sebastian River (designated a Class III Aquatic Preserve by the Florida Department of Environmental Protection [FDEP]), and in the IRT.. system, an Estuary of National Significance, by capturing stormwater runoff and routing it into a series of detention facilities for treatment prior to discharge. TI. E'S'TIMATED POLLUTANT LOAD REDUCTION: The construction permit (DISTRICT Permit #4-061-0163AGC-ERP) for Vero Lakes Estates includes typical block Swale improvements throughout the subdivision, various ditch improvements, and four (4) lake area stormwater improvements. COUNTY estimates that the average annual total suspended solids (TSS) pollutant load reduction would be *80% for the Vero Lakes Estates area, which is routed through the hakes upon completion of all improvements within the subdivision area. This Scope of Work addresses upgrading the majority of the subdivision's stortttwater systems east of 98`x` Avenue, including two lake area stormwater improvements with ditch improvements to interconnect the lakes, canal reshaping and cleaning, and road paving throughout tate project area. COUNTY estimates a 60% reduction in [lie TSS annual pollutant load from this segment of Vero Lakes Estates upon completion of this work. Page 9 of 28