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Future of Hillsborough Comprehensive Plan for Unincorporated Hillsborough County Florida CONSERVATION AND AQUIFER RECHARGE As Amended by the Hillsborough County Board of County Commissioners June 5, 2008 (Ordinance 08-13) Department of Community Affairs Notice of Intent to Find Comprehensive Plan Amendments in Compliance published August 4, 2008 {DCA PA No. 08-1ER-NOI-2901- (A)-(l) August 26, 2008 Effective Date 1 Hillsborough County Conservation and Aquifer Recharge Hillsborough County Conservation and Aquifer Recharge TABLE OF CONTENTS PAGE II. INTRODUCTION ............................................................................................... 5 III. INVENTORY AND ANALYSIS .............................................................................. 7 IV. GOALS, OBJECTIVES, AND POLICIES ............................................................... 36 Hillsborough County Conservation and Aquifer Recharge 2 List of Tables TABLE 1 WATERSHED PLAN PRIORITIES ................................................................ 25 TABLE 2 AIR QUALITY FOR TAMPA METROPOLITAN AREA ......................................... 33 3 Hillsborough County Conservation and Aquifer Recharge I. EXECUTIVE SUMMARY Hillsborough County, by virtue of its subtropical climate and variable hydrology and geology, supports a rich and diverse complement of natural resources. The County borders the largest estuary in the State, Tampa Bay, and three major rivers (the Hillsborough, Alafia and Little Manatee) flow through the County's borders. The County is underlain by the Floridan AquiferAquifer, the largest and highest quality potable water aquifer in the State, as well as by some of the richest phosphate deposits in the world. The karst topography of the County has created a mosaic of solution sinks and depressions which contain a wide variety of wetland flora and fauna, while the higher well-drained elevations support rare xeric hammocks and scrub habitat. The role of the Conservation and Aquifer Recharge Element is to maintain or improve the quality of the County's environment and natural resources, and its citizens' quality of life, in light of the anticipated population growth. The Conservation and Aquifer Recharge Element must work in harmony with the Future Land Use, Coastal Management and Port, Community Facilities, Transportation and other elements of the Future of Hillsborough Comprehensive Plan for Unincorporated Hillsborough County in ensuring environmental protection while fostering economic growth and development. Hillsborough County Conservation and Aquifer Recharge 4 II. INTRODUCTION PURPOSE OF CONSERVATION AND AQUIFER RECHARGE ELEMENT The purpose of the Conservation and Aquifer Recharge Element is to provide a plan and policy direction for the preservation, conservation, and management of the natural resources of Hillsborough County. This element is intended to provide guidelines for future governmental programs and decisions related to the protection and enhancement of the County's natural environment, as well as the public health, safety and welfare. The objective of the Conservation and Aquifer Recharge Element is to ensure that the air, land, water and living resources of Hillsborough County remain an asset, rather than become a liability, to the quality of life of all existing and future inhabitants. NEED FOR CONSERVATION AND AQUIFER RECHARGE ELEMENT Hillsborough County, by virtue of its subtropical climate and variable hydrology and geology, supports a rich and diverse complement of natural resources. The County borders the largest estuary in the State, Tampa Bay, and three major rivers (the Hillsborough, Alafia and Little Manatee) flow through the County's borders. The County is underlain by the Floridan Aquifer, the largest and highest quality potable water aquifer in the State, as well as by some of the richest phosphate deposits in the world. The karst topography of the County has created a mosaic of solution sinks and depressions which contain a wide variety of wetland flora and fauna, while the higher well-drained elevations support rare xeric hammocks and scrub habitat. Over the past century, however, development has slowly degraded the rich natural resources of the County. The unregulated filling of wetlands, discharge of pollutants, mining of phosphate deposits, clearing of forests, dredging of bay bottoms, channeling of streams and rivers, and over pumping of groundwater supplies has irretrievably destroyed or altered much of the original natural resource base. Environmental legislation passed at the federal, state, regional and local levels over the past three decades has done much to stem the tide of this destruction; however, advance planning and further safeguards will be needed to ensure the preservation and conservation of the County's remaining natural resources for future generations. ELEMENT ORGANIZATION The Conservation and Aquifer Recharge Element is comprised of three integral parts including the Inventory and Analysis; the Goals, Objectives and Policies; 5 Hillsborough County Conservation and Aquifer Recharge and the Plan Implementation and Monitoring sections. The Inventory and Analysis section presents historic and current conditions upon which to base the recommended planning and management strategies. The Goals, Objectives and Policies section presents the recommended planning guidelines, programs and other operative provisions which are intended to drive private and governmental decisions regarding natural resources. Finally, the Plan Implementation and Monitoring section recommends probable strategies and intergovernmental coordination for implementing the goals, objectives and policies. Hillsborough County Conservation and Aquifer Recharge 6 III. INVENTORY AND ANALYSIS GEOGRAPHIC SETTING Hillsborough County is located on the coast of west-central Florida, bounded on the west by Tampa Bay and Pinellas County, on the east by Polk County, on the north by Pasco County, and on the south by Manatee County. Hillsborough County has a surface area of approximately 1,072 square miles. Land-surface altitudes range from sea level along the coast to approximately 160 feet above sea level at the Hillsborough-Polk County line southeast of Keysville. Hillsborough County can be broken down into five physiographic provinces (White, 1970). The provinces are the Coastal Swamps, the Gulf Coastal Lowlands, the Zephyrhills Gap, the Polk Upland, and the DeSoto Plain. The physiographic areas are primarily a function of topographic relief and underlying sediments. The Coastal Swamps and Gulf Coastal Lowlands areas lie between the Tampa Bay estuary and the Polk Uplands in southeastern Hillsborough County and range in width from 2 miles to approximately 12 miles. Elevations of land surface range from sea level to 90 feet above sea level. Soils are characteristically sandy and contain little organic material. The Polk Upland is the dominant topographic feature in southeastern Hillsborough County, extending eastward from central Hillsborough County and south from the Hillsborough River valley. The western edge is a gentle slope and the northern edge follows the drainage basin ridge between the Hillsborough and Alafia Rivers. Its siliclastic composition has contributed to the topographic character of these areas, for in most of the Polk Upland, the effects of solution sinks are not as intense as they are generally throughout peninsular Florida, and surface streams are much more prominent here. Elevations range up to 160 feet above sea level in the Polk Uplands, a poorly drained plateau underlain by deeply weathered sand and clay-rich sand. The uplands have flatwoods with cypress heads and strands existing in most places, with thick, well drained sands along the margins. The Alafia and Little Manatee Rivers originate in the Polk Uplands with widely branching tributaries. A small portion of the DeSoto Plain is in south-central Hillsborough County. This plain is similar to the Polk Upland but very flat. The Zephyrhills Gap is the southernmost surface water drainage outlet from the central Florida valley, between the central ridge and the Ocala Uplift. This area follows the Hillsborough River valley; which is an erosional basin with sluggish surface drainage and many karst features. Much of the clastic sediments have been removed in northeast Hillsborough County. A thin sand and clay layer overlie karst limestone in this Gap area. Many sinkholes and springs occur in the Hillsborough River connecting it with the Floridan Aquifer. 7 Hillsborough County Conservation and Aquifer Recharge Elevations range from 10 to 140 feet above sea level. The Hillsborough valley is much older than the other rivers in the County, which is evident from the ancient beach terraces cut back by the Hillsborough River that are not cut by the Alafia River. Poorly drained swamps and marshes support cypress and wetland vegetation, while flatwoods are found on the higher ground. Major surface drainage features in Hillsborough County are the Hillsborough, Alafia, and Little Manatee Rivers (Figure 1). The Hillsborough River begins in the Green Swamp and flows southwestward, draining 690 square miles before emptying into Hillsborough Bay. The Alafia begins in Polk County and flows westward, draining a 420 square mile basin, and also enters Hillsborough Bay. The Little Manatee River begins in southeast Hillsborough County and northeast Manatee County and flows west to Tampa Bay, draining 225 square miles. Much of the precipitation in northwest Hillsborough