USGS Home
SOFIA Home

Flow Velocity and Water Level Transects

Metadata also available as - [Outline] - [Parseable text] - [XML]

Frequently-anticipated questions:

What does this data set describe?

Title: Flow Velocity and Water Level Transects
Abstract:
The sheet flow over the Buttonwood Embankment during periods of high flow is an unknown element of the water budget for the Everglades. An ongoing project to estimate the flows over the embankment through modeling will require water-level and water velocity data measured at the embankment to accurately estimate simulated flows over this physical land feature. The actual measurement of water velocities and depths at the embankment would greatly improve the model calibration. Although it is virtually impossible to conventionally measure flow over the entire embankment, water depths and velocities at known points along the embankment, combined with the detailed topography of the embankment being developed in another ongoing project, should allow a much better estimate of the total flow than presently available.
Supplemental_Information:
This project has been integrated into the TIME project. The project was started by Marvin Franklin
  1. How should this data set be cited?

    Dan Nowacki Ray Schaffranek (retired) Marvin A. Franklin (retired), 2005, Flow Velocity and Water Level Transects.

    Online Links:

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -80.4
    East_Bounding_Coordinate: -80.2
    North_Bounding_Coordinate: 25.7
    South_Bounding_Coordinate: 25.5

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Calendar_Date: Jul-1997
    Currentness_Reference: ground condition

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: spreadsheet

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Point data set.

    2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:
      UTM_Zone_Number: 17
      Transverse_Mercator:
      Scale_Factor_at_Central_Meridian: 0.9996
      Longitude_of_Central_Meridian: -81
      Latitude_of_Projection_Origin: 0
      False_Easting: 500000
      False_Northing: 0

      Planar coordinates are encoded using Coordinate Pair
      Abscissae (x-coordinates) are specified to the nearest 0.001
      Ordinates (y-coordinates) are specified to the nearest 0.001
      Planar coordinates are specified in meters

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.
      The flattening of the ellipsoid used is 1/298.257.

  7. How does the data set describe geographic features?

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

    Velocity data and cross section data was collected by Paul Meadows, Darlene Blum, Mark Stephens, Greg Donley, Kenny Kalan, Don Goin, Gina Tillis, Eric Swain, John Pittman, Alex Gallagher, James Dubuisson, Harry Jenter, and Lavetra Sloan.

  3. To whom should users address questions about the data?

    Dan Nowacki
    U.S. Geological Survey
    430 National Center
    Reston, VA 20192
    USA

    703 648-5467 (voice)
    dnowacki@usgs.gov

Why was the data set created?

The objective of the project is to make the best possible estimate of the flow velocities and water depths across Buttonwood Embankment during high flow for use as model input for an ongoing project being conducted in the USGS-WRD office in Miami. Estimates will be used to provide management alternatives and will create salinity concentrations suitable for ecologic integrity.

How was the data set created?

  1. From what previous works were the data drawn?

  2. How were the data generated, processed, and modified?

    Date: Jul-1998 (process 1 of 1)
    Measurement sites were restricted to areas along established airboat trails. Initially internal flows were measured across three transect lines (T1, T2, and T3) bisecting the Taylor Slough Basin from east to west as well as a transect along the centerline of the axis of the slough. In November 1997, a fourth transect (T4) was added to the data collection effort, connecting transects T2 and T3 along a north-south airboat trail. Three-dimensional velocity measurements were conducted at the transect sites using ADVs. Water depth, water-quality parameters, litter-layer thickness, weather conditions, site description, site location, bottom conditions, and vegetative cover were recorded concurrently with ADV measurements. Individual velocity sampling sites were chosen to be representative of the vegetation type and density as well as water depth in the surrounding area.

    Four intensive data-collection trips into the Taylor Slough Basin were conducted during July, September, and November 1997 and July 1998. These trips coincided with precipitation events that produced sufficient water levels for airboat access and covered a wide range of water levels and flow conditions. The ADV meters provided the required levels of accuracy in flow-velocity measurements while enabling rapid collection of multiple time-series of flow data at remote sites. Concurrently, flow measurements were made along bordering road culverts and under L-31W and Taylor Slough bridges. At sites where the use of acoustic instruments was impractical, vertical-axis current meters were used to measure water velocity.

    Water-quality meters (collected with all velocity profiles) collected data at middepth and measured the temperature, specific conductance, salinity, dissolved oxygen, and pH. Measured temperature and salinity values were use in computation of water velocity. All water-quality meters were calibrated at the beginning of each day.

    After positioning the ADV for a velocity measurement with minimal disturbance to the surrounding vegetation and flow field, the hydrographer retreated from the probe and the presumed flow path. About 2 minutes was allowed for the sample area to return to equilibrium before starting a velocity measurement. Measurement bursts lasted 120 seconds, at a 10 hertz sampling rate, and produced time-series measurements of 1200 pints at the appropriate depths in the water column.

    Person who carried out this activity:

    Dan Nowacki
    U.S. Geological Survey
    430 National Center
    Reston, VA 20192
    USA

    703 648-5467 (voice)
    dnowacki@usgs.gov

  3. What similar or related data should the user be aware of?

    Tillis, G. M., 2001, Measuring Taylor Slough boundary and internal flows, Everglades National Park, Florida: USGS Open-File Report 01-225, U.S. Geological Survey, Tallahassee, FL.

    Online Links:

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

  2. How accurate are the geographic locations?

    Global Positioning System (GPS) instrumentation established horizontal sampling locations in North American Datum of 1983 (NAD83) coordinates. Field notes included the latitude and longitude coordinates, GPS drift, and description of distinctive features (nearby staff gages and cypress heads). These coordinates were converted to UTM coordinates (NAD83, Zone 17) for reporting and modeling purposes.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    Data was collected in July, September, and November 1997 and July 1998. Not all sites have data for all collection dates. See the individual datasets for available data.

  5. How consistent are the relationships among the observations, including topology?

    Velocity and flow were collected for Transects One, Two, Three, and the Stationary Transect. Velocity only was collected for Transect Four and C-11. Discharge measurements made with conventional meters are available in the Culverts dataset.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: none
Use_Constraints: none

  1. Who distributes the data set? (Distributor 1 of 1)

    Heather S.Henkel
    U.S. Geological Survey
    600 Fourth St. South
    St. Petersburg, FL 33701
    USA

    727 803-8747 ext 3028 (voice)
    727 803-2030 (FAX)
    hhenkel@usgs.gov

  2. What's the catalog number I need to order this data set?

    Flow and Velocity data

  3. What legal disclaimers am I supposed to read?

    The data have no explicit or implied guarantees.

  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 23-Mar-2007
Metadata author:
Heather Henkel
U.S. Geological Survey
600 Fourth Street South
St. Petersburg, FL 33701
USA

727 803-8747 ext 3028 (voice)
727 803-2030 (FAX)
sofia-metadata@usgs.gov

Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)

This page is <http://sofia.usgs.gov/metadata/sflwww/flow_velocity.faq.html>

U.S. Department of the Interior, U.S. Geological Survey, Center for Coastal Geology
Comments and suggestions? Contact: Heather Henkel - Webmaster
Generated by mp version 2.8.18 on Fri Mar 23 16:17:21 2007