For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. ForewordThe U.S. Geological Survey (USGS) is committed to providing the Nation with reliable scientific information that helps to enhance and protect the overall quality of life and that facilitates effective management of water, biological, energy, and mineral resources (http://www.usgs.gov/). Information on the Nation's water resources is critical to ensuring long-term availability of water that is safe for drinking and recreation and is suitable for industry, irrigation, and fish and wildlife. Population growth and increasing demands for water make the availability of that water, measured in terms of quantity and quality, even more essential to the long-term sustainability of our communities and ecosystems.The USGS implemented the National Water-Quality Assessment (NAWQA) Program in 1991 to support national, regional, State, and local information needs and decisions related to water-quality management and policy (http://water.usgs.gov/nawqa). The NAWQA Program is designed to answer: What is the quality of our Nation's streams and groundwater? How are conditions changing over time? How do natural features and human activities affect the quality of streams and groundwater, and where are those effects most pronounced? By combining information on water chemistry, physical characteristics, stream habitat, and aquatic life, the NAWQA Program aims to provide science-based insights for current and emerging water issues and priorities. From 1991 to 2001, the NAWQA Program completed interdisciplinary assessments and established a baseline understanding of water-quality conditions in 51 of the Nation's river basins and aquifers, referred to as Study Units (http:// water.usgs.gov/nawqa/studyu.html).In the second decade of the Program (2001-2012), a major focus is on regional assessments of water-quality conditions and trends. These regional assessments are based on major river basins and principal aquifers, which encompass larger regions of the country than the Study Units. Regional assessments extend the findings in the Study Units by filling critical gaps in characterizing the quality of surface water and groundwater, and by determining water-quality status and trends at sites that have been consistently monitored for more than a decade. In addition, the regional assessments continue to build an understanding of how natur...

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Future DirectionsOver the past five years from the inception of the USGS Place-Based Program, the focus has mainly been on program planning, data collection, process studies, and development of modeling tools. Several projects have now completed or are nearing completion of this phase and have entered into the phase of data analysis, credibility assurance (quality assurance) initial reporting, KEEPING ON COURSE -MODELS, MONITORING AND PERFORMANCE INDICATORS Visions and goals are inherently conceptual. Results are concrete.Translating one into the other, especially on the scale required by south Florida ecosystem, is challenging. The restoration project is using models, monitoring, restoration, and performance indicators to translate conceptual ideas to the real world, adapt projects to changing conditions, and provide accountability.Models -Restoration workers employ a series of computerized models to predict the responses of key variable to changing environmental, social, or economic conditions. Developing simulations that forecast responses to different scenarios permits researchers to identify management alternatives as well as target conditions that will yield desired goals. Computerized models also can be updated as new information is gained, allowing predictions to be continually refined.Monitoring -An adaptive management strategy demands continual feedback. Developing and implementing monitoring programs are a major emphasis for many restoration projects. Some monitoring tracks variables subject to rapid change. Other monitoring programs record long term trends. Monitoring data are essential in assessing the effectiveness of restoration actions, tracking progress, and identifying problems or the need for project modification.Performance Indicators -The restoration project also uses quantitative indicators (levels of phosphorus in runoff) and qualitative indicators (quality of life) to track and assess projects. Comparing actual conditions against predicted targets provides a yardstick for measuring the progress (were are we now, how much farther to go?) and for evaluating the results (what are the benefits/are they worth the costs). Models, monitoring, and performance indicators provide direction, feedback, and accountability for both short and long-term actions. This affords flexible, timely, and responsible management of projects and project funds. Ground-water discharge (G i ) 0.09 (3) 0.06 (2) 2 0.35 (13) Ground-water recharge (G o ) 1 0.88 (31) 0.84 (30) 3 0.90 (32) Net ground-water flux (G i -G o ) -0.78 1 -0.78 1 -0.55 1 Estimated by difference between other two estimates in each column. 2 Estimated using results from Guardo and Prymas (1998). 3 Estimated using results from Hutcheon Engineers (1996).

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The bibliographic list of publications which follows is arranged alphabetically by senior author. The publications are also indexed by geographic area (see p. VIII) and by subject.V