Laserfiche WebLink
' <br />4.0 EXISTING CONDITIONS <br />4.1 PHYSICAL DESCRIPTION <br />The study area of Rockridge is located in east central Indian River County, <br />' <br />Florida, west of the Intracoastal Waterway (Indian River) at approximately <br />27°37' north latitude and 80020' west longitude. The weather is mild, with <br />' <br />a mean annual temperature of 72.60. This is due in part to the County's <br />proximity to the north -flowing Gulfstream in the Atlantic Ocean. Rainfall <br />' <br />in the study area averaged 64.27 inches for the period from 1982-1986. <br />4.1.1 HYDROLOGY <br />Indian River County is underlain by two aquifers, these aquifers referred <br />' <br />to as the shallow aquifer and the Floridan aquifer. Both aquifers are <br />regional and are separated from each other by a confining unit. <br />' <br />The shallow aquifer (also known as the surficial aquifer) begins at land <br />' <br />surface and extends to a depth of from 100 to 150 feet below land surface <br />(bls). At the study site, the shallow aquifer extends to approximately 150 <br />' <br />feet bls. The shallow aquifer consists of layers of sand, shell, and clay <br />which deposited <br />were during the Pleistocene age. These layers of <br />sedimentary material are collectively known as the Anastasia Formation. <br />' <br />The Anastasia Formation does not make up the entire shallow aquifer in that <br />it grades toward the west into a fine grained sand unit known as the Fort <br />' <br />Thompson Formation. The Fort Thompson Formation contains only a few <br />consolidated sandstone layers. <br />' Collectively, the two formations of the shallow aquifer exhibit good <br />porosity however poor effective porosity. The permeability of the shallow <br />' aquifer is quite restricted due to the irregular nature of the <br />interconnection of voids between the sand grains. Yields from 10 -inch <br />' IRC.VB4 <br />6/4/87 <br />4-1 <br />