FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION
VERSION 2004
TITLE: SURFACE WATER NUTRIENT SAMPLING SITES
Geodataset Name: NAWQAN Geodataset Type: SHAPE Geodataset Feature: POINT
GENERAL DESCRIPTION:
This dataset contains the sampling sites and data for the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program Study-Unit investigations of Surface Water Nutrients for the conterminous United States, excluding the High Plains Regional Ground-Water Study. DATA SOURCE(S): USGS SCALE OF ORIGINAL SOURCE MAPS: NA DATE OF AUTOMATION OR SOURCE: 1999 GEODATASET EXTENT: State of Florida
Datafile Name: NAWQAN.DBF ITEM NAME WIDTH TYPE PRECISION SHAPE 6 SHAPEPOINT 0 SU 10 CHARACTER - SITE 254 CHARACTER - NAME 30 CHARACTER - SAMP_TYPE 10 CHARACTER - LU_TYPE 30 CHARACTER - URBAN 8 DECIMAL 3 AGRICULTUR 8 DECIMAL 3 RANGELAND 8 DECIMAL 3 FOREST 8 DECIMAL 3 WATER 8 DECIMAL 3 WETLANDS 8 DECIMAL 3 OTHER 8 DECIMAL 3 LAT_DD 8 DECIMAL 3 LON_DD 8 DECIMAL 3 STATION 50 CHARACTER - DATEN 8 DATE - TIMEN 8 DECIMAL 5 PURPOSE 50 CHARACTER - P00060 8 DECIMAL 5 P00061 8 DECIMAL 5 P00010 8 DECIMAL 5 P00095 8 DECIMAL 5 P00300 8 DECIMAL 5 P00400 8 DECIMAL 5 P00915 8 DECIMAL 5 P00925 8 DECIMAL 5 P00930 8 DECIMAL 5 P00935 8 DECIMAL 5 PALK 8 DECIMAL 5 P00940 8 DECIMAL 5 P00945 8 DECIMAL 5 R00950 10 CHARACTER - P00950 8 DECIMAL 5 P00955 8 DECIMAL 5 P01046 8 DECIMAL 5 P01056 8 DECIMAL 5 P70300 8 DECIMAL 5 P00608 8 DECIMAL 5 R00613 10 CHARACTER - P00613 8 DECIMAL 5 R00631 10 CHARACTER - P00631 8 DECIMAL 5 R00623 10 CHARACTER - P00623 8 DECIMAL 5 P00625 8 DECIMAL 5 R00671 10 CHARACTER - P00671 8 DECIMAL 5 R00666 10 CHARACTER - P00666 8 DECIMAL 5 P00665 8 DECIMAL 5 DESCRIPT 30 CHARACTER -
FEATURE ATTRIBUTE TABLES CODES AND VALUES:
ITEM ITEM DESCRIPTION SHAPE Data attribute inherent to the ESRI shapefile format, which defines the data as a point, polyline, or polygon. SU USGS station identification number SITE USGS station identification number NAME Site Name SAMP_TYPE Sampling Type; to identify the reason a particular sample was collected. Can be helpful in aggregating groups of samples for analysis and interpretation. LU_TYPE Land Use Type Urban Agricultur Rangeland Forest Water Wetlands Other URBAN Percent Urban Land Use AGRICULTUR Percent Agriculture Land Use RANGELAND Percent Rangeland Land Use FOREST Percent Forest Land Use WATER Percent Water Land Use WETLANDS Percent Wetlands Land Use OTHER Percent Other Land Use Lat_dd Latitude; in degrees, minutes, seconds Lon_dd Longitude; in degrees, minutes, seconds STATION USGS station identifier DATE Date of sampling event or measurement TIMEN Time of sampling event or measurement PURPOSE Purpose code for sampling collection P00060 Mean daily streamflow, feet cubed per second P00061 Instantaneous daily streamflow, feet cubed per second P00010 Water temperature, degrees Celcius (C.) P00095 Specific conductance, microsiemens (us)/cm@25 degrees C. P00300 Dissolved oxygen, mg/L P00400 pH, whole water, field standard units P00915 Calcium, dissolved, mg/L as Ca P00925 Magnesium, dissolved, mg/L as Mg P00930 Sodium, dissolved, mg/L as Na P00935 Potassium, dissolved, mg/L as K PALK Alkalinity, mg/L as CACO3 (mostly field titration of filtered water) P00940 Chloride, dissolved, mg/L as Cl P00945 Sulfate, dissolved, mg/L as SO4 P00950 Fluoride, dissolved, mg/L as F P00955 Silica, dissolved, mg/L as SiO2 P01046 Iron, dissolved, ug/L as Fe P01056 Manganese, dissolved, ug/L as Mn P70300 Residue, dissolved, at 180 degrees C., mg/L P00608 Ammonia, dissolved, mg/L as N P00613 Nitrite, dissolved, mg/L as N P00631 Nitrite and nitrate, dissolved, mg/L as N P00623 Ammonia and organic nitrogen dissolved, mg/L as N P00625 Ammonia and organic nitrogen, total, mg/L as N P00671 Orthophosphate, dissolved, mg/L as P P00666 Phosphorus, dissolved, mg/L as P P00665 Phosphorus, total, mg/L as P DESCRIPT FGDL added item based on Name item
USER NOTES:
The National Water-Quality Assessment Program is designed to describe the status and trends in the quality of the Nation's ground- and surface-water resources and to provide a sound understanding of the natural and human factors that affect the quality of these resources (Leahy and others, 1990). A "Study Unit" is a major hydrologic system in which NAWQA studies are focused. Study Units are geographically defined by a combination of ground- and surface-water features (Gilliom and others, 1995). As part of the NAWQA program, Study-Unit investigations were planned for 60 areas throughout the Nation to provide a framework for national and regional water-quality assessments (Leahy and others, 1990). The 60 planned Study-Units were divided into three groups of 20. Each group would be intensively studied on a rotational basis with 20 studies beginning in fiscal year 1991 (FY 1991 runs from October 1990-September 1991), 20 more studies beginning in fiscal year 1994 (October 1993-September 1994), and the final 20 studies beginning in fiscal year 1997 (October 1996-September 1997). Each study cycle would span 10 years. In 1996, the number of Study-Units was scaled back to 59 when two of the original 60 Study Units combined. Also, because of budgetary restraints, some of the original planned Study Units have been scheduled to start later than originally planned and others have not even been scheduled to start yet. This shapefile contains basic geographic information about a subset of the 213 surface water sites that were sampled for nutrients as part of NAWQA within the conterminous United States, excluding the High Plains Regional Ground Water-Study, which was conceived in late 1997. This shapefile only contains the 5 surface water sites located in the state of Florida. The dataset for the entire conterminous United States can be obtained from the following EPA website: http://www.epa.gov/airmarkets/cmap/data/index.html. This shapefile also includes the NAWQA standard abbreviation of each Study Unit, the station identification code, sampling type, land-use type, percentages of specific land use types, and latitude and longitude coordinates. The stream data are the results from 8459 water samples collected at 213 surface water sites across the conterminous United States. All of the sampling sites are located in the 20 major watersheds that comprise the first group of NAWQA study units. Samples were collected from October 1991 through December 1996. About 90 percent of the samples were collected during 1993, 1994, and 1995. All samples were flow-weighted and cross-sectionally integrated by standard USGS methods (Ward and Harr, 1990). Complete descriptions of sample collection and processing methods are provided by Shelton (1994). Sampling at many sites was not spaced evenly throughout the year. Sampling at the intensive fixed sites was more frequent during periods when pesticide levels were expected to be elevated. At the basic fixed sites, extra samples were collected during extreme flow conditions. Thus, care must be used in the interpretation of these data. For example, summary statistics such as the mean or median concentration for a specific compound may be biased unless procedures are used to account for the uneven sampling frequency. In addition, the number of samples collected varied considerably among the sites. Thus, the results shown in the surface water data file are influenced more by conditions at some sites than others. Data analysis procedures that account for this unequal distribution of samples among the sites must be used to avoid biased interpretations. This data set is used primarily to display the location of NAWQA Surface Water Nutrient Study Sites and for use with the NAWQA Study Unit boundaries shapefile (NAWQA) for analysis of data at the national scale. It is not recommended for either local or regional analysis due to the small scale of most of the features. A note concerning data scale: The dataset provides location and attribute information for use in national and regional cartographic and network analysis applications. Scale is an important factor in data usage. Certain scale datasets are not suitable for some project, analysis, or modelling purposes. Please be sure you are using the best available data. 1:24000 scale datasets are recommended for projects that are at the county level. 1:24000 data should NOT be used for high accuracy base mapping such as property parcel boundaries. 1:100000 scale datasets are recommended for projects that are at the multi-county or regional level. 1:250000 scale datasets are recommended for projects that are at the regional or state level or larger. Vector datasets with no defined scale or accuracy should be considered suspect. Make sure you are familiar with your data before using it for projects or analyses. Every effort has been made to supply the user with data documentation. For additional information, see the References section and the Data Source Contact section of this documentation. For more information regarding scale and accuracy, see our web pages at: http://www.geoplan.ufl.edu/education.html
FGDL QUALITY ASSURANCE STATUS:
-Projected data to FGDL Albers HPGN (See "Map Projection Parameters" below). -Clipped to the State of Florida -DESCRIPT item added based on NAME -Upcased all character records -Linked with nutrient data file -Dropped items AREA PERIMETER NUTRIENT_S NUTRIENT_1 In addition the following fields had no data so they were dropped: R00010 R00095 R00300 R00400 R00915 R00925 R00930 R00935 Ralk R00945 R00955 R01046 R01056 R70300 R00608 R00625 R00665
DATA LINEAGE SUMMARY:
This data was originally released by USGS in 1999. In 2002, the GeoPlan Center downloaded this dataset in shapefile format from the EPA Downloads website: http://www.epa.gov/airmarkets/cmap/data/index.html. When received, the shapefile was in the following projection: Albers, Datum: NAD 83, Spheroid: GRS80, Units: Meters. The shapefile was then clipped to the State of Florida and reprojected to FGDL Albers HPGN (See "Map Projection Parameter" below). The DESCRIPT item was added based on NAME, old internal coverage items were dropped (AREA PERIMETER NUTRIENT_S NUTRIENT_1), all character records within the attribute table were upcased, and fields with no values were removed.
MAP PROJECTION PARAMETERS:
Projection ALBERS Units METERS Datum HPGN Spheroid GRS1980 1st standard parallel 24 0 0.000 2nd standard parallel 31 30 0.000 Central meridian -84 0 0.000 Latitude of projection's origin 24 0 0.000 False easting (meters) 400000.00000 False northing (meters) 0.00000
DATA SOURCES CONTACT(S):
Name: U.S. Geological Survey Abbr.name: USGS Address: 12201 Sunrise Valley Drive, MS-413 Phone: 703-648-6854 Contact Person: Kerie J. Hitt Email: kjhitt@usgs.gov
FGDL CONTACT:
Name: Florida Geographic Data Library Abbr. Name: FGDL Address: Florida Geographic Data Library 431 Architecture PO Box 115706 Gainesville, FL 32611-5706 Web site: http://www.fgdl.org Contact FGDL: Technical Support: http://www.fgdl.org/fgdlfeed.html FGDL Frequently Asked Questions: http://www.fgdl.org/fgdlfaq.html FGDL Mailing Lists: http://www.fgdl.org/fgdl-l.html For FGDL Software: http://www.fgdl.org/software.html