Project Work Plan

Study Title: Hydrodynamic and Bathymetric Characteristics of Estuarine Rivers within the Ten Thousand Islands Aquatic Preserve (this task is work order no. 5 under the existing agreement with SFWMD on project “Resolution Bathymetric Mapping of South Florida Estuarine and Coastal Systems”)
Study Start Date: October 1, 2004 Study End Date: November 30, 2005
Web Sites:
Location: 10000 Islands, Everglades National Park, Southwest Florida
Funding Source: USGS Greater Everglades Priority Ecosystems Science (GE PES)
Other Complementary Funding Source(s): Cooperative funding from South Florida Water Management District
Principal Investigator(s): Mark Hansen and Eduardo Patino
Study Personnel: Gina Peery, Lars Soderqvist, Craig Thompson, Jeff Woods, Ruth Coastley
Supporting Organizations: SFWMD
Associated / Linked Studies:

Overview & Objective(s):

During the last few decades, the coastal environments of south Florida have shown signs of ecological deterioration that has been attributed to changes in freshwater inflows caused by management practices and corresponding increases of salinity and nutrient content in estuarine waters. With plans to restore water levels in the Southern Golden Gate Estates area north of Tamiami Trail to more natural conditions, changes are expected in the amount, timing, and distribution of freshwater discharge through bridges and culverts under US-41, and therefore altering current conditions in the wetlands and estuaries to the south. Bathymetric and hydrologic information throughout the Ten Thousand Islands Aquatic Preserve and adjacent ecosystems is critical for the development and calibration of hydrodynamic models that would help with the evaluation of restoration results. With construction of the Southern Golden Gate Estates Hydrologic Restoration and Tamiami Trail Culvert projects underway, the need to determine the physical characteristics of rivers and bays within the areas to the south of US-41 that will be greatly impacted by both of these projects, becomes even more urgent. There are significant physical information gaps throughout the wetlands and estuaries within the study area that still need to be addressed. Among these gaps are the bathymetry of rivers and bays of the Ten Thousand Islands Preserve, estimates of freshwater flows across the Trail, groundwater information within the marshes south of Tamiami Trail (including specific conductance/salinity), surface flows at or near the mouth of tributaries for the determination of contaminant transport, water level, and salinity data throughout the area. The results of this study will prioritize information needs (bathymetric and hydrologic) for all tributaries flowing into the Ten Thousand Islands Aquatic Preserve, by conducting bathymetric surveys along priority estuarine rivers and offshore coastal areas and by describing the hydrodynamic characteristics of estuarine rivers (tidal magnitudes) and relevance to the overall circulation and mixing patterns of the area.

This project has two objectives. The purpose of Task 1 is to describe the hydrodynamic characteristics of estuarine rivers of the Ten Thousand Islands Aquatic Preserve, from Barron River to Palm Bay. The purpose of Task 2 is to conduct bathymetric surveys along priority estuarine rivers and offshore coastal areas within the Ten Thousand Islands Aquatic Preserve.

Specific Relevance to Major Unanswered Questions and Information Needs Identified: (Page numbers below refer to DOI Science Plan.)

This study supports regional “landscape-scale” hydrologic models which are a high priority issue in the DOI science plan. Landscape-scale modeling helps managers understand and plan for how multiple projects will interrelate across broad geographic areas under multiple jurisdictions. For example, the South Florida Water Management District (SFWMD) Model (2 x 2 Model) provides a picture of how the regional water management system works (Pg 18). Also, several recent initiatives including the development Minimum Flows and Levels (MFL) and the Southwest Florida Feasibility Study necessitate the development of hydrodynamic models of coastal waters in South Florida. The next generation hydrologic model that uses higher resolution in key areas, known as the South Florida Regional Simulation Model (RSM), is being developed by SFWMD. Two higher resolution (500 x 500 meters) hydrologic models, known as the TIME and SICS, are available for the southern Everglades and are being used to predict salinity in the coastal wetlands (Pg 18). Additional models, particularly at local levels, and linkages among models are needed for the detailed design and adaptive management of individual projects.

One of the important data requirements for all these models is the bathymetry. High resolution, GPS based bathymetric surveying is a proven method to map river, lake, and ocean floor elevations. The information available at this time for most of South Florida is dated and needs to be upgraded with new surveys. Updated bathymetry provided by this project supports several efforts in the DOI science plan including the Caloosahatchee, Loxahatchee, and St. Lucie MFL, the Southwest Florida Feasibility Study, and the S.W.I.M. designation of Charlotte Harbor.

Status:

Ongoing. This project is a continuation of work order no. 5 under the existing agreement with SFWMD on project “Resolution Bathymetric Mapping of South Florida Estuarine and Coastal Systems”. The project begins on October 1, 2004.

Recent Products:

High-resolution bathymetric data sets and maps extending from Charlotte Harbor to Estero Bay including the Caloosahatchee River and Pine Island Sound. Also, swath bathymetry data of the following rivers in Southwest Florida: Shark, Little Shark, Harney, Broad, Lostman's, Lopez, Chatham, Hudson, and Turner.

Planned Products:

High-resolution bathymetric data set of the 10,000 Island Region in southwest Florida

WORK PLAN

Title of Task 1: Hydrodynamic Characteristics of Estuarine Rivers within the Ten Thousand Islands Aquatic Preserve
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES)
Task Leaders: Eduardo Patino
Phone: (239) 275-8448
FAX: (239) 275-6280
Task Status (proposed or active): Active
Task priority: High
Task Personnel: Eduardo Patino, Lars Soderqvist, Craig Thompson, Jeff Woods, Ruth Coastley

Task Summary and Objectives:

Hydrologic information will be collected at the main tributary rivers flowing into the Ten Thousand Islands Aquatic Preserve, including (1) Barron River, (2) Ferguson River/Tide Creek, (3) East River, (4) Fakahatchee River, (5) Faka Union River, (6) Wood River, (7) Little Wood River, (8) Pumpkin River, (9) Whitney River, (10) Blackwater River, and (11) Palm Bay River. The information to be collected include time-series data for water level, velocity, salinity, and temperature, for a period not to exceed 3-months. Acoustic Doppler Velocity Meters (ADVM) equipped with an up-looking transducer will be installed to facilitate the collection of water stage and velocity with one single instrument. ADCP discharge measurements will be made for the development of Index-Velocity calibration ratings at all instrumented sites. 13-hr ADCP measurement sessions will be made to capture the tidal characteristics of these rivers, and used for rating development. Discharge will be computed for the 3-month period for all stations, and analyzed to describe tidal magnitudes that include possible variations due to meteorological events, such as rain and wind. Priorities for bathymetric and hydrologic information needs will be set by the comparison of these tidal magnitudes at all measured rivers.

Work to be undertaken during the proposal year and a description of the methods and procedures:

The hydrodynamic characteristics of 11 rivers (Barron River, Ferguson River/Tide Creek, East River, Fakahatchee River, Faka Union River, Wood River, Little Wood River, Pumpkin River, Whitney River, Blackwater River, and Palm Bay River) will be described by performing the following subtasks:

• Subtask 1 - Collect water level, velocity, salinity, and temperature time-series data for a period not to exceed 3 months.
• Subtask 2 - Perform ADCP discharge measurements sessions (up to 13-hr periods), to capture flow conditions over a complete tide cycle (or as much as possible, depending on field conditions).
• Subtask 3 - Develop Index-Velocity ratings for the computation of a 3-month period of discharge record.
• Subtask 4 - Conduct analysis of discharge and salinity records for the description of the hydrodynamic characteristics of all measured rivers, and assign priorities for the collection of bathymetric and long-term hydrologic data, based on tidal magnitudes.

Specific Task Product(s):

• Subtask 1 - Make available to GEPES and SFWMD by June 30, 2005 all final quality assured time-series data collected during the 3-months period. Data collection will be completed by February 28, 2005. Data will be posted into the USGS SOFIA web site.
• Subtask 2 - Measurements sessions will be completed by January 31, 2005. Data will be posted into the USGS SOFIA web site.
• Subtask 3 - Index-velocity ratings will be completed by February 28, 2005 and made available upon request.
• Subtask 4 - Complete analysis of discharge and salinity records and assign priorities for the collection of bathymetric and long-term hydrologic data, based on tidal magnitudes. This task will be completed by June 30, 2005.

Title of Task 2: Bathymetric Surveys of Estuarine Rivers and Offshore Coastal Areas within the Ten Thousand Islands Aquatic Preserve
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES)
Task Leaders: Mark Hansen
Phone: (727) 803-8747 ext 3036
FAX: (727) 803-2030
Task Status (proposed or active): Active
Task priority: High
Task Personnel: Mark Hansen, Gina Peery

Task Summary and Objectives:

High resolution, GPS based bathymetric surveying is a proven method to map river, lake, and ocean floor elevations. Several recent initiatives including the development Minimum Flows and Levels (MFL) and the Southwest Florida Feasibility Study (SWFFS) necessitate the development of hydrodynamic models of coastal waters in South Florida. One of the important data requirements for these models is accurate bathymetry. The information available at this time for most of South Florida is dated and needs to be upgraded with new surveys.

This project addresses the collection and interpretation of data necessary to develop the present day bathymetry of the lower portions of South Florida including the bathymetry of rivers and bays within the Ten Thousand Islands Preserve. In order to create accurate numerical models, current bathymetric data must be obtained. Bathymetry data is also needed for the creation of seagrass vision maps (a National Estuary program (NEP) effort) and to populate the species response models being created as assessment tools for several restoration programs. The strategy is to acquire bathymetric data for the aforementioned areas employing a USGS acoustic based system named System for Accurate Nearshore Depth Surveys (SANDS). This USGS system can acquire data in water depths of ~25cm, but in practice boat/motor draft limitations prevent surveying in water depths less than 45cm. Precise differential GPS receivers are used to measure boat position and dynamic elevation, a survey quality 200 kHz depth sounder acquires water depth measurements, and a motion sensor measures heave, pitch, and roll of the boat. A measurement is collected about every 3m along a survey line. The vertical accuracy of the system is +/- 8cm and +/- 4cm inches horizontally.

Work to be undertaken during the proposal year and a description of the methods and procedures:

The bathymetric surveys of estuarine rivers and offshore coastal areas within the Ten Thousand Islands Aquatic Preserve will be described by performing the following subtasks:

• Subtask 1 - Conduct a bathymetry meeting between the USGS team and District staff to discuss the bathymetry tasks of the project.
• Subtask 2 - Conduct inspection of areas to be surveyed.
• Subtask 3 - Complete all fieldwork associated with conducting high-resolution bathymetric survey.
• Subtask 4 - Complete data analyses and reports

Specific Task Product(s):

• Subtask 1 - Project staff will provide to SFWMD a summary of the technical exchange that takes place at the bathymetry meeting.
• Subtask 2 - Inspection of areas to be surveyed will be completed before June 2005.
• Subtask 3 - Bathymetric surveys will be completed by August 2005. On completing the fieldwork associated with the bathymetry tasks, project staff shall notify PES and SFWMD in writing and deliver a draft meta-data that includes a description of field conditions and a summary field log. All metadata will be stored into the USGS SOFIA web site.
• Subtask 4 - Project staff shall provide post processing of the benchmark and hydrographic data, store and maintain all data and provide access to this data for reproduction as needed. At the conclusion of the project, project staff shall provide a final data package to include the following:
  1. Hard copy plot of locations of surveyed areas.
  2. Digital ASCII XYZ data in UTM Zone17, GRS80/NAD83 horizontal coordinates, and NAVD88 vertical coordinates in tabular format. A copy of the coordinates in State Plane Coordinate (SPC) Feet Florida East Zone NAD83 shall also be provided, consistent with District GIS database.
  3. Copies of raw and processed digital data files on CD-ROM. All data shall comply with SFWMD GIS data requirements.