Project Summary Sheet

Study Title: Freshwater Flows to Northeastern Florida Bay
Study Start Date: 1995 Study End Date: TBD
Web Sites: http:(//sofia.usgs.gov/projects/freshwtr_flow/)
Location (Subregions, Counties, Park or Refuge): Miami-Dade and Monroe Counties, Everglades National Park
Funding Source: USGS Greater Everglades Priority Ecosystems Science (GE PES), U.S. Army Corps of Engineers (USACE)
Principal Investigator(s): Mark Zucker, Clinton Hittle
Study Personnel: Jeff Woods, Marc Stewart, Barclay Shoemaker, Paul Stumpner, Shane Ploos, Christrian Lopez
Supporting Organizations: USACE, South Florida Water Management District (SFWMD), Everglades National Park (ENP)
Associated / Linked Studies: Southwest Florida Coastal and Wetland Systems Monitoring, Tides and Inflow in the Mangrove Ecotone (TIME), Groundwater-Surface Water Interactions and Relation to Water Quality in the Everglades, Geology and Ecological History of the "Buttonwood Ridge" Region, Salinity Patterns in Florida Bay: A Synthesis, Interrelation of Everglades Hydrology and Florida Bay Dynamics to Ecosystem Processes and Restoration in South Florida, Southern Inland and Coastal Systems (SICS) Model Development

Overview & Objective(s): The project objectives are to: 1) determine the quantity, timing and distribution of freshwater flow through estuarine creeks into northeastern Florida Bay, 2) provide real-time scientific data for Everglades modeling and research, and 3) advance accurate methods for gaging estuarine creeks. Flow, water level, and salinity data are collected at estuarine creeks that connect the Everglades wetlands to Florida Bay. This project helps determine how freshwater flow affects the health of Florida Bay, a critical concern of the Comprehensive Everglades Restoration Plan (CERP), and how changes in water-management practices upstream (Taylor Slough and C-111 basins) directly influence flow and salinity conditions in the estuary. The USACE, SFWMD, USGS, ENP, and other agencies as well as universities are currently using the data from this study to answer specific research questions that will directly benefit the restoration effort.

Status: On-going

Recent Products: Published unit values of water level, discharge, salinity, and temperature are available from water year 2001 to water year 2004 for selected stations. Data can be acquired from the USGS South Florida Information Access (SOFIA) database at http://sofia.usgs.gov/exchange/patino/patinoflow.html.

Published manuscripts for selected stations are available in the South Florida Surface Water Data Book at http://water.usgs.gov/pubs/wdr/2004/wdr-fl-04-2a/.

A coastal network map with links to the National Water Information system (NWIS) (real-time status) has been developed and is available at http://fl.water.usgs.gov/Miami/hurricane/.

Planned Products: Published unit values of water level, discharge, salinity, and temperature for water year 2005 and any additional unpublished record. Data will be available from the USGS South Florida Information Access (SOFIA) database.

Manuscripts for selected stations will be published in the 2006 South Florida Surface Water Data Book.

Specific Relevance to Information Needs Identified in DOI's Science Plan in Support of Ecosystem Restoration, Preservation, and Protection in South Florida (DOI's Everglades Science Plan) [See Plan on SOFIA's Web site: http://sofia.usgs.gov/publications/reports/doi-science-plan/]:

This study supports several of the projects listed in the DOI science plan (specifically; The C-111 Spreader Canal and Combined Structural and Operations Plan (CSOP), Additional Water for ENP and Biscayne Bay Feasibility Study; Florida Bay and Florida Keys Feasibility Study) by providing (a) baseline hydrologic data for model calibration and verification, and resource management; (b) discharge at estuarine creeks to determine the quantity, timing and distribution of freshwater flow; (c) discharge at estuarine creeks for load calculations; (d) temperature data for biological studies; and (e) salinity data to determine whether restoration criteria (performance measures) are being met.

This study supports the C-111 Spreader and CSOP projects ("Science Plan" p. 71) by providing (1) critical coastal discharge data to determine nutrient and pesticide loading to the bay, and (2) salinity data to calibrate models or verify model predictions of salinity.

This study supports the Additional Water for ENP and Biscayne Bay Feasibility Study (p. 74) by providing (1) critical coastal discharge data to quantify nutrient and pesticide loading to the bay (p. 63) and (2) baseline data to help determine how restoring natural flows to Taylor Slough will change the quantity, timing, and distribution of flows in Biscayne Bay.

This study supports the Florida Bay and Florida Keys Feasibility Study (p. 77) by providing (1) baseline data to help determine the quantity, timing and distribution of freshwater flow to Florida Bay (2) basic hydrologic data to assist with model calibration and verification (p. 78) of the Florida Bay Hydrodynamic and the USGS TIME and SICS models, and (3) critical coastal discharge data to help determine nutrient, pesticide, and mercury loading.

Key Findings:

1. From 1996 to 2003, Trout Creek has consistently contributed approximately 50% of the total freshwater flow to northeastern Florida Bay.
2. During water year 2004, (as well as water years 1998, 1999, 2000, and 2001), hypersaline conditions (near 40 ppt) were observed in the westernmost portion of the study area. Hypersaline conditions (near 40 ppt) were also observed during water year 2004 in the easternmost portion of the study area.
3. During water year 2005, hypersaline conditions exceeding 50 ppt and near 40 ppt were observed in the westernmost and easternmost portion of the study area, respectively. The hypersaline gradient in northeastern Florida Bay was further documented by a moving boat salinity survey conducted on May 20, 2005, as part of the Coastal Gradients Project.
4. Preliminary data suggest that freshwater flow to northeastern Florida Bay during water year 2004 was the lowest contribution since data collection activities began in water year 1996.