Technical reports

A technical memorandum that provides cost estimating and economic criteria to be used in the development of water supply facilities costing for the 2005 District Water Supply Plan.

This technical memorandum reports on an analysis to determine the relative comparative impact of using an alternative water supply source upon the cost of delivered potable water for typical local utilities in east-central Florida.

This report presents a review of the literature for five selected centrarchid species to provide information for the determination of biologically meaningful minimum flows and levels.

The goal of this study was to provide answers to outstanding questions about the character and causes of algal blooms in Lake Griffin that have a direct bearing on the management of the ecosystem.

This study is the most complete sediment quality assessment to date of the Cedar-Ortega River Basin and shows that the sediments are widely contaminated with a variety of organic and metal contaminants. The information from this assessment will be used to guide management efforts to protect and restore the basin’s natural resources.

The purpose of this preliminary investigation was to identify, examine, and evaluate issues involved in development of Lake Apopka as a supplemental supply for the city of Apopka reuse system.

The objectives of this project are to develop a conceptual water resources model of sandhill lakes and, based on this model, to identify significant water resource, environmental, and socioeconomic values of sandhill lakes and to evaluate whether these values can be sufficiently defined to develop criteria under the relevant F.A.C. rules.

This handbook describes water resource constraints and defines thresholds (for planning purposes) beyond which unacceptable impacts to water quality and to wetland and aquatic systems are expected to occur.

For this study, a model was developed to provide small-area population projections for the 18 counties within the St. Johns River Water Management District, upon which the future water demand projections are based.

This report documents work toward objectives to better understand the multiple price signals sent to customers via block rate structures, to assess how wealth an price sensitivity are related, and understanding and factoring in source substitution for irrigation. Researchers set a goal of generating decision-making concerns for rate design, water use and revenue forecasting, resource planning and customer support.

The objective of this study was to determine biota sediment accumulation factors of different organochlorine pesticides (OCPs) in two biota species (Eastern mosquitofish, Gambusia holbrooki and calico crayfish, Orconectes immunis) in relation to varying levels of OCP and total organic carbon (TOC) content of soils collected throughout the North Shore Restoration Area of Lake Apopka.

The report provides scientific information for elected officials and interested persons to support the decision-making process to implement aquifer storage and recovery technology. Demonstration sites throughout the district’s service area were used to determine the extent to which ASR can be applied to meet local or regional needs through use of alternative water supplies.

Field experiments were conducted at five golf courses in central Florida to evaluate the performance of irrigation systems and to evaluate the effects of irrigation amounts on turf quality and rooting depths.

The St. Johns River Water Management District initiated a project to update a sinkhole database to include sinkholes that had occurred since 1992 and to make initial evaluations of sinkhole occurrences throughout the district. This report does this and expands on a database that documents sinkholes from 1984 to 1992 that was compiled by the Florida Sinkhole Research Institute at the University of Central Florida.

The report documents the update to 2002 modeling efforts in east-central Florida by the district to address water supply planning needs. This report looks at the original groundwater model and its interaction with a new surface water model.

This report documents how the flow model simulates the effects that increased groundwater pumpage in north-central Florida will have on water levels in the surficial aquifer system and the upper Florida aquifer, groundwater system water budgets and spring flows.

The report documents the study done to determine appropriate injection well design requirements for disposal of liquid generated by demineralization processes used to produce drinking water. An evaluation methodology was developed and described to aid in determination of the appropriate well design and construction technology requirements based on concentrate corrosion rate factors.

This report outlines the assessment made of the level of precision achieved by best management practices (sample set compared to targets) in a 1988 study, the extent to which the Benchmark Farms project data are consistent with expectations for irrigation data, and recommendations for quality assurance checks that can be implemented into the data collection and recording process to ensure data integrity.

This document is the third in a series of annual reports of the activities and accomplishments for the East-central Florida Water Supply Planning Initiative that was designed to educate local governments, water supply utilities and the public about water supply issues facing the east-central Florida area, and to encourage cooperation and coordination in developing solutions to the regional problems. A further goal of the initiative is to begin implementing projects to meet the area’s future water supply needs.

This report compares the use of wetland protection criteria in water supply planning at the St. Johns River Water Management District to the South Florida Water Management District and the Southwest Water Management District.

This report assesses the conditions of selected constraint wetlands and water bodies used in the east-central Florida groundwater optimization model. This evaluation could be used to determine if the constraint wetlands and water bodies continue to have value as indicators of unacceptable impacts to water supplies.

This report analyzes the underlying causes of the 1998-99 bird mortality at the North Shore Restoration Area of Lake Apopka and reviews key components of the mortality event.

This report addresses the decline in aggregate surface outflow from the Harris Chain of Lakes and the reasons for the reduction in outflow.

The objective of this study was to examine key aspects of the structure and function of algal blooms in Lake Griffin in order to investigate possible causes for the structure and dynamics of blooms. Two primary sampling sites were established in Lake Griffin, and samples were collected over a 19-month period.

The East-Central Florida Water Supply Planning Initiative is designed to assist local governments and water supply utilities in meeting future water supply needs while protecting the water resources and related natural systems. Initiative activities in 2003 were focused on Volusia, Brevard, Orange, Seminole, Lake, and Osceola counties. The primary focus was on developing new water supply.

This report documents the process, activities, and results of the modeling subgroups in workgroup areas I, II, and V. Documentation includes the minutes of the subgroup meetings, model peer review comments and recommendations, and results of the modeling subgroup process.

This report summarizes the findings of Task C.5 for the seawater demineralization feasilbility investigation which involved the development of comparative-level cost estimates and concept designs for the five preferred sites.

This technical memorandum was prepared to provide the St. Johns River Water Management District with information on current desalination technologies and an update on advancements in the industry.

The purpose of Task C.1 is to develop criteria suitable for use as a preliminary (macro level) screening measure within the coastal areas of the St. Johns River Water Management District for siting seawater demineralization facilities. Task C.1 represents the first step in the multi-step process of site identification. This step identifies whether or not a site has preferred features.

The purpose of Task B.6 is to present rules and regulations applicable to the permitting of seawater demineralization plants in the St. Johns River Water Management District. These rules, regulations, and permit requirements are important to an understanding of some of the restraints and schedule considerations associated with a seawater demineralization facility.

This annotated bibliography represents the body of knowledge concerning demineralization technology, concentrate disposal, permitting, and economics related to seawater demineralization in the United States.

This report discusses the methodology applied to develop the list of five preferred sites. It also includes the results of the intermediate screening steps and identifies the five preferred sites.

This study was undertaken to directly collect water quality data from a seawater demineralization system operating in the St. Johns River Water Management District (SJRWMD) for comparison to surface water discharge regulatory requirements. Surface water discharge is the most common method utilized worldwide for discharge of seawater demineralization concentrate and is a likely alternative for any future seawater demineralization facilities built in SJRWMD.

This report contains applicable rules and regulations as they relate to demineralization concentrate management, as well as recommendations for potential actions to support an environmentally sound, logical, and clear regulatory process.

This bibliography is the result of a literature survey and a review of existing reports, articles, and other literature specifically related to demineralization technology and the environmental and cultural impacts of demineralization concentrate management. The information in those reports and publications has been entered into an electronic database.

This bibliography is the result of a literature survey and a review of publications specifically related to investigations of the surface water and groundwater of the St. Johns River Water Management District and of the hydrologic, geologic, and quality parameters associated with those waters.

This document provides information to support the relational database and GIS data layers required as part of this project.

This paper reports on an evaluation process undertaken to determine a feasible organizational and financial framework for developing new water supply sources.

The objective of this study was to determine how river levels affected fish abundance and communities, using a long-term dataset from several Florida rivers to evaluate trends, in order to facilitate the establishment of minimum flows and levels.

This technical memorandum presents results of a service area demand study used to determine the projected water demands for surface water in Volusia and Seminole counties through 2025.

The purpose of this study was to demonstrate the treatability of a specific water source, identify the appropriate technology and basic design parameters for treatment, and determine the capital and operational costs for a potential facility to produce potable water from the St. Johns River.

The purpose of this technical memorandum is to provide a general overview and basic summary of the different types of treatment technology that could potentially be applied to a specific surface water source. The report also references recent studies that are applicable to treatment of surface water from the St. Johns River.

This technical memorandum was developed to review the raw water characteristics of the St. Johns River. These data are being summarized for use in the evaluation and selection of appropriate treatment processes for the pilot program.

The purpose of this report is to outline the methodology that will be used to accomplish the primary objectives of the plan, which are to establish and maintain effective communication with key stakeholders, to identify and resolve issues, and to develop community support.

The purpose of this report is to outline the methodology that will be used to complete the siting study.

The purpose of this report is to present the methods, analysis, and results of the Levels 1 and 2 siting analysis phases.

The purpose of this report is to present the methods, analysis, and results of the Level 3 analysis.

This report presents results of the affordability analysis conducted as part of the St. Johns River water supply project, which was conducted to determine the feasibility of using water from the St. Johns River as a potable water source as an alternative to groundwater.

This report identifies potential water supply development projects that were not identified in the district water supply plan of 2000.

The purpose of this report was to evaluate whether the preliminary minimum flows and levels established by the St. Johns River Water Management District for the St. Johns River near DeLand will provide protection to the estuarine resources, as required by Rule 62040.471(1)(c), Florida Administrative Code.

The purpose of this study was to conduct an environmental assessment and to determine whether the preliminary minimum flow and level for the St. Johns River near DeLand at State Road 44 protects specified natural resource and environmental values.

This report addresses methods to assess changes in detrital transfer and sediment transport (and load) as part of the protocol for minimum flows and levels in rivers and lakes.

This report is a summary of the districtwide and detailed assessment performed between 1997 and 2002.

The objective of this project was to predict the rates of deposition, erosion, and transport of fine sediment, to evaluate proposed remedial dredging works, and to develop management strategies in the lower Cedar/Ortega rivers.

Seven human use and ecological water resource values were evaluated in this report. The purpose of this report is to present an evaluation, within the constraints of existing data, concerning whether any of these values will require minimum flows more stringent than those developed for protection of the Blue Spring manatee population.

This project was undertaken to establish a baseline of knowledge for visitor characteristics, including economic impacts and associated recreational values, for eight priority springs in the St. Johns River Water Management District, priority springs being those springs prioritized for the establishment of minimum flows and levels.

This report contains brief descriptions of each of the rare endemic and non-endemic plants and rare land and riverine vertebrates, non-rare endemic plant species, and rare natural communities that were documented in a survey done by the Florida Natural Areas Inventory.

This report identifies and documents a series of appropriate methods for assessing changes to filtration and absorption of nutrients and other pollutants and water quality related to hydrologic conditions imposed by minimum flows and levels.

This report identifies five classes of “self-supply well reduction in or loss of service” in the St. Johns River Water Management District.

Information from the Florida Natural Areas Inventory database is provided for rare species and rare natural wetland community types for 19 priority springs within the St. Johns River Water Management District.

This report summarizes information concerning the life histories of three diadromous fishes in the St. Johns River — American shad, hickory shad, and American eel — that may be affected by changing water flows and levels, to support the establishment of appropriate minimum flows and levels.

This report presents a preliminary evaluation of the supplemental data collected at 20 surface water sites in the lower St. Johns River basin.

Local government officials, water supply utilities, and the St. Johns River, South Florida, and Southwest Florida water management districts began working together through the Initiative to develop solutions to their collective water supply issues. This document summarizes, by issue area, 2004 Initiative Phase II activities and provides recommendations for activities in 2005.

This report presents the findings of a basinwide sediment quality assessment conducted within the Lower St. Johns River Basin, 1996–1999. The objective was to determine the presence, concentration, and distribution of potentially toxic organic compounds and metals.