U.S. Geological Survey         Data Series 105

By Clinton D. Hittle and Mark A. Zucker

Northeastern Florida Bay Estuarine Creek Data, Water Years 1996-2000

Data Series 105 Abstract and Conversion Table Introduction, Figure 1, & Table 1 Methods of Investigation Field Data Collection Discharge Computation for Instrumented Sites, Tables 2 & 3 Discharge Estimation for Noninstrumented Sites Data Files - Northeastern Florida Bay Estuarine Creeks References Cited

Discharge Computation for Instrumented Sites Discharge was computed on a 15-minute interval at instrumented sites using mean water velocity and the cross-sectional area of the channel. Velocity and area relations developed for each site were used to calculate discharge time-series data for all instrumented sites along the northeastern coastline of Florida Bay. The ADCP was used to determine channel depth at specific distances across the width of each creek. These depths were used with simultaneous stage readings to develop a relation between water level and total cross-sectional area for the individual sites.   To develop a time-series record of mean water velocity for any stream using acoustic velocity data, a relation must be established between the AVM or ADVM velocities and directly measured ADCP mean water velocity. Three case scenarios, based on a velocity estimation model, describe flows under varying conditions at the instrumented sites in Florida Bay. These scenarios are presented and discussed in Hittle and others (2001).   The velocity relation (discharge rating) for West Highway Creek was revised after publication of Hittle and others (2001). Separate discharge ratings were originally required to compute positive and negative flow, and the negative flow equation was stage dependent (Hittle and others, 2001). Equation 1 is a simplified rating that was subsequently developed to compute mean positive and negative water velocities for West Highway Creek between 1996-2000, independent of stage. The rating was developed using a simple linear regression:          V = 0.874Vi – 0.013     (1) R2 = 0.96   where V is mean water velocity, Vi is acoustic line velocity and R2 is the coefficient of determination. Equation 1 is based on the mathematical formula in Hittle and others (2001, eq. 3).   Stillwater Creek, located in western Long Sound, was instrumented in 1999 to establish a better understanding of freshwater flow entering Long Sound. Prior to instrumentation, Stillwater Creek discharge was estimated using discharge from West Highway Creek; however, the estimation equation R2 value was the lowest of all the creeks (table 2).     Table 2. Discharge estimation equations for noninstrumented sites [Abbreviations: Q, discharge; QWHWY is discharge value at West Highway Creek, QMUD is discharge at Mud Creek, QTAY is discharge value at Taylor River, and QTRT is discharge at Trout Creek] Station Name Discharge Estimation Primary Formula Coefficient of Determination (R2) Alternate Formula Coefficient of Determination (R2) 1 Formulas for East Highway, Oregon, and Stillwater Creeks revised after publication of Hittle and others (2001, p. 17). 2 Instrumented beginning mid-1999. 3 Discharge estimation formulas and R2 value from Hittle and others (2001). East Highway Creek1 Q=0.44QWHWY - 5.4 0.95 Q=0.28QTRT - 5.4 0.92 Oregon Creek1 Q=0.25QWHWY - 0.43 0.90 Q=0.05QTRT + 11.8 0.85 Stillwater Creek1,2 Q=0.27QWHWY + 5.2 0.84 Not developed Not applicable East Creek3 Q=0.827QWHWY + 10.7 0.99 Q=0.76QTAY - 7.0 0.87   Upstream Taylor River, which is located about 2 mi north of the mouth of Taylor River, represents wetland creek flows, whereas the Taylor River site represents flow through the coastal embankment. The upstream site was instrumented in 1999 to obtain a better understanding of flow in creeks that lie within the Everglades wetlands. There is no estimated record prior to the installation of this site due to the present lack of correlation between the upstream and downstream Taylor River sites. All currently instrumented sites, except for Upstream Taylor River and Stillwater Creek, have continuous 15-minute record during water years 1996-2000 (table 3).     Table 3. Period of record for Florida Bay monitoring stations [Period of record is given in water years, except where noted] Station Name Type of Site Period of Record Estimated Continuous 15-minute East Highway Creek Noninstrumented 1996 - 2000 Not applicable West Highway Creek Instrumented Not applicable 1996 - 2000 Oregon Creek Noninstrumented 1996 - 2000 Not applicable Stillwater Creek Instrumented beginning 1999 1996 - mid-1999 mid-1999 - 2000 Trout Creek Instrumented Not applicable 1996 - 2000 Mud Creek Instrumented Not applicable 1996 - 2000 East Creek Noninstrumented 1996 - 2000 Not applicable Taylor River Instrumented Not applicable 1996 - 2000 Upstream Taylor River Instrumented beginning 1999 Not applicable mid-1999 - 2000 McCormick Creek Instrumented Not applicable 1996 - 2000

U.S. Department of the Interior,
U.S. Geological Survey
9100 N.W. 36th Street
Miami, FL 33178
email Clinton D. Hittle cdhittle@usgs.gov or Mark A. Zucker mzucker@usgs.gov