Technical reports

The Floridan aquifer system is the primary source of water supply in the Wekiva River surface water basin. The principal reason for establishing minimum levels and flows in the Wekiva Basin was to ensure that flow from artesian springs emanating from the Floridan aquifer system and the base flow of each stream would be adequate to prevent significant harm to aquatic and wetland resources. Additionally, minimum flows and levels are to be a consideration for the declaration of a water shortage.

The reconnaissance reports compile information and make recommendations to help resource managers identify priority needs for research into and management of the Lower St. Johns River Basin (LSJRB). This volume reviews and summarizes work relating to aquatic and wetland biological communities in the LSJRB.

A two-phase study was conducted to evaluate the flooding problems of the basin and to formulate a comprehensive flood management plan to reduce flood and erosion damages. Water quality and environmental conditions in the basin were assessed. An analysis of water quality in the basin, environmental conditions, and wetland loss was also part of this study.

Water use data were collected by county and compiled by category of use. Water use covers all water withdrawals from groundwater or surface water sources. The appendix presents specific data for each county.

Lake Washington is the major drinking water supply source for south Brevard County. The lake is dammed at its north end by a temporary sheet-pile weir, constructed in 1976. Because lake levels have receded below the weir crest during extended droughts, a permanent weir has been recommended. This report identifies potential weir sites and provides a hydrologic and environmental evaluation.

MODVIEW version 1.0 is a graphical-kernel-system program that enables datasets arranged in the format of a two-dimensional array to be viewed as colored patterns of numerical ranges.

This assessment identifies areas in which water resource problems have become critical or are projected to become critical within 20 years (through the year 2010) and identifies remedial or preventive actions designed to correct or prevent these problems.

The information used to compile this report has been reduced into a series of tables containing data from aquifer tests.

This report is the tenth annual abandoned artesian well inventory and work plan for controlling or plugging inventoried wells. An appendix lists plugged and repaired wells by county.

The SSARR hydrologic model and the DWOPER hydraulic model can simulate flooding potential for Black Creek at a given time. Three tasks that need to be accomplished before these models can be used in real-time simulation and warning are discussed.

A well-planned flood warning system contains three general components: scientific, emergency management, and public response. This report focuses on the data collection network of the scientific component. The existing flood warning network for the drainage basin is not extensive enough to provide adequate data to represent conditions in the basin. This report outlines six options that will aid in flood forecasting.

Recharge areas of the Floridan aquifer in the St. Johns River Water Management District were mapped using a geographic information system to analyze the geologic and hydrologic factors that affect recharge.

The reconnaissance reports compile information and make recommendations to help resource managers identify priority needs for research into and management of the Lower St. Johns River Basin. This volume discusses sedimentation processes, as well as the lack of information on sedimentation processes and characteristics.

The reconnaissance reports compile information and make recommendations to help resource managers identify priority needs for research into and management of the Lower St. Johns River Basin. This volume examines the relationship and influence of the interconnection between the lower St. Johns River and the groundwater flow system associated with the river.

The reconnaissance reports compile information and make recommendations to help resource managers identify priority needs for research into and management of the Lower St. Johns River Basin. Volume 2 is an overview of the surface water system and the existing rainfall and streamflow monitoring networks in the lower basin.

The goal of the Surface Water Improvement and Management (SWIM) program is to protect or restore significant water bodies. The SWIM priority list will guide the selection of water bodies for SWIM programs. The list was developed from a quantitative analysis to identify the most significant surface water subbasins in the district. Significance was evaluated using socioeconomic and ecological criteria, in conjunction with criteria that defined the need for management action based on water quality concerns. This list is a supplement to an earlier report which introduced the 1991 SWIM priority list.

To determine the hydrologic dynamics of the Upper Etonia Creek system and to evaluate possible measures toward mitigating the low lake levels, the surface water hydrology of the Upper Etonia Creek chain of lakes was simulated with the SSARR model.

Water use data were collected by county and compiled by category of use. Water use covers all water withdrawals from groundwater or surface water sources. The appendix presents specific data for each county.

This report is the ninth annual abandoned artesian well inventory and work plan for controlling or plugging inventoried wells. An appendix lists plugged and repaired wells by county.

The Little Wekiva River basin is highly urbanized, and street flooding, damages to residential and commercial buildings, losses of bridges and culverts, and channel and bank erosion can occur within the basin during major storms. A two-phase study evaluated the flooding problems of the basin and formulated a comprehensive flood management plan to reduce flood and erosion damages. Water quality and environmental conditions in the basin were also assessed.

This report presents rainfall distributions for specific surface water drainage basins in the district for the convenience of applicants for Management and Storage of Surface Water permits, consulting engineers, and other users.

The primary objective of this research was to develop a finite-difference groundwater flow model that could be used to predict the response of the Floridan aquifer system of the Jacksonville area of northeast Florida to various pumping scenarios. The model used was MODFLOW. The predevelopment (prior to 1880) and current Floridan aquifer systems were modeled as steady-state systems consisting of three aquifer layers separated by three confining-unit layers. The overall calibration system consisted of two phases.

This inventory includes data for 222 wastewater treatment plants with permitted capacities of 0.1 million gallons per day or greater and located within or serving areas within the St. Johns River Water Management District. Information may be used to identify sources of treated wastewater for potential reuse.

Water use data were collected by county and compiled by category of use. Water use covers all water withdrawals from groundwater or surface water sources. The appendix presents specific data for each county.

Fifty-eight samples were collected from nine pumps in the upper basin to characterize the water quality of agricultural discharges. Water quality was characterized based on dissolved oxygen levels, suspended solids, chloride, nutrient levels, nitrate-nitrite nitrogen, and total phosphorus.

This report, part 4 of a series, presents the results of frequency analysis of warm season and cold season rainfall. The report is based on the collection and detailed analysis of rainfall data and directed at a specific hydrologic/engineering study goal.

This report, part 5 of a series, presents the results of frequency analysis of wet season and dry season rainfall. The report is based on the collection and detailed analysis of rainfall data and directed at a specific hydrologic/engineering study goal.

Water use data were collected by county and compiled by category of use. Water use covers all water withdrawals from groundwater or surface water sources. The appendix presents specific data for each county.

The Floridan aquifer is the primary source of water supply in northeast Florida. The effects of increased growth and urbanization along the coast have raised concerns about the long-term availability of potable groundwater supplies. This report presents a preliminary examination of water resource problems, concentrating on the occurrence of saline water in the Floridan aquifer in the coastal areas of Nassau, Duval, and northern St. Johns counties.

A residential area located on the north shore of Lowry Lake in north-central Polk County experienced localized flooding during high stages in the lake. A water management study completed by the St. Johns River Water Management District in 1987 identified diversion of floodwaters from the lake into the Upper Peace River Basin, located in the Southwest Florida Water Management District, as the most cost-effective of several flood control alternatives. This report presents the results of a re-evaluation of the diversion alternative under specific discharge criteria.

The Hicks Ditch basin, an 18.2-square-mile watershed east of Lake Eustis and south of the Ocala National Forest, experiences periodic flooding, resulting in damages to agricultural levee systems and standing water on farm lands. This floodplain study is the first step toward the development of a water management plan for the Hicks Ditch basin.

This report provides a general inventory of the groundwater resources of the lower St. Johns River and St. Marys River groundwater basins, including hydrogeologic features, recharge and discharge areas, groundwater quality characteristics, present and projected water use, direct water reuse, and areas suitable for future water resource development.

The identification of groundwater recharge areas is an important part of managing water resources to ensure future availability of groundwater and to protect groundwater quality. The recommended areas of prime groundwater recharge, as defined by this report, are the areas within a groundwater basin that contribute the greatest volume of water per unit area to the Floridan aquifer. A geographic information system methodology was used to delineate the recharge areas of the Floridan aquifer in this study.

The upper St. Johns groundwater basin is one of five groundwater basins in the St. Johns River Water Management District and is located largely in Brevard and Indian River counties. This report provides a general inventory of the water resources of the upper St. Johns groundwater basin, including hydrogeologic features, recharge and discharge areas, groundwater quality characteristics, present and projected water use, direct water reuse, and areas suitable for future water resource development.

The middle St. Johns groundwater basin is one of five groundwater basins in the St. Johns River Water Management District and is almost entirely within Lake, Seminole, Marion, and northern Orange counties. This report provides a general inventory of the water resources of the middle St. Johns groundwater basin, including hydrogeologic features, recharge and discharge areas, groundwater quality characteristics, present and projected water use, direct water reuse, and areas suitable for future water resource development.

Water use data were collected by county and compiled by category of use. Water use covers all water withdrawals from groundwater or surface water sources. The appendix presents specific data for each county.

The purpose of this report is to assess the accuracy of the Blaney-Criddle method of estimating irrigation requirements. Water use for potatoes was investigated during the 1985-86 growing season. This study resulted in a determination of the supplemental irrigation requirements for potatoes at selected sites and an estimation of the areawide quantity of groundwater withdrawn for this crop.

This report documents rainfall data for use in the district’s stormwater management program, the engineering requirements of water storage analysis and water supply planning.

This report documents work done at the request of city of Port Orange to determine the potential for saltwater intrusion into the surficial aquifer.

This report documents a study of flooding conditions in the Little Wekiva River Basin to develop a comprehensive floodplain management plan for the basin.

This report provides a general inventory of water resources in Volusia County, including hydrogeologic features.

This report documents the general water quality in the Wekiva River basin, using current and historical data.

The study was to collect, evaluate and present data on the lithologic and hydrostratigraphic nature of the Floridan aquifer.

The objectives of this study were to (1) describe the occurrence and movement of groundwater in the Floridan, intermediate, and surficial aquifers, (2) identify areas of saltwater intrusion, (3) examine the relationship between groundwater withdrawals and the occurrence of saltwater intrusion, (4) determine the historical impact of groundwater withdrawals on water levels and quality, and (5) synthesize all available data and assess the effect of growth on available potable water.

This report presents the results of the effort to develop a groundwater flow model of the Floridan aquifer system in the specified counties. A numerical model of the artesian groundwater flow system in the area was developed (1) to provide an improved description of the regional hydrogeologic characteristics of the Floridan aquifer system in the study, (2) to provide a starting point for development of a model capable of predicting the movement of saline groundwater in the study area, (3) to develop a more sophisticated and realistic water budget of the area than has previously been available, and (4) to develop a tool with which to assess the regional impacts of large-scale stresses on the groundwater flow system.

This report, sixth in a series, continues the project “Rainfall Analysis for Northeast Florida.” Forty-six tables present maximum rainfall depth data.

This report consists of 14 wetland vegetation quad maps.

Summary not available.

Summary not available.

Summary not available.

The purpose of this study was to determine the areal extent of the Sebastian freshwater lens, to document the changes in its size with time, and to project the future utility of the lens. This report contains a quantitative appraisal of the Floridan aquifer producing zones.

The purpose of this project was to design an observation well network from which data could be collected to evaluate the impacts of withdrawals from the lower permeable zone of the Floridan aquifer. This report proposes a network of deep monitoring wells in the Orlando and Winter Park area.

The objective of this report was to define the hydrologic criteria required to maintain the ecological integrity of the marshflat flora and fauna downstream of the Lake Washington weir. The project was expanded to include an assessment of minimum surface water requirements for Lake Washington, as well as for the area north of the lake.

This study was undertaken to evaluate the water supply potential of Lake Washington and to develop an appropriate water management plan for Lake Washington and the river downstream.

The purpose of this study was to develop and evaluate solutions to the problem of localized flooding at Lowry Lake. As part of the study, the socio-economic, hydrologic, and site-specific characteristics of the study area were qualified and quantified. This was done by computer simulations of design configurations developed as possible solutions.

The vegetation of trails both frequently and infrequently traveled by tracked off-road vehicles, as well as the vegetation of untraveled areas, was examined to ascertain the effects of this type of traffic through the three major communities of the floodplain: maidencane wet prairie, sawgrass wet prairie, and tree island.