FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION
TITLE: MAJOR DAMS
Geodataset Name: MJDAMS Geodataset Type: SHAPE Geodataset Feature: POINT
GENERAL DESCRIPTION:
This dataset contains major dams of the State of Florida.
DATA SOURCE(S): United States Geological Survey SCALE OF ORIGINAL SOURCE MAPS: 1 :2,000,000 DATE OF AUTOMATION OR SOURCE: 1999 GEODATASET EXTENT: State of Florida
FEATURE ATTRIBUTE TABLES:
Datafile Name: MJDAMS.DBF Datafile Name: MJDAMS.DBF ITEM NAME WIDTH TYPE PRECISION SHAPE 6 SHAPEPOINT 0 NID_ID 7 CHARACTER - DAM_NAME 65 CHARACTER - OTHER_NAME 65 CHARACTER - HAZARD 11 CHARACTER - STATE_NAME 20 CHARACTER - COUNTY 30 CHARACTER - RIVER 30 CHARACTER - PRM_PURPOS 15 CHARACTER - NID_DAMTYP 8 CHARACTER - YEAR_COMPL 11 DECIMAL - NID_HEIGHT 8 DECIMAL - OWN_TYPE 14 CHARACTER - NEAR_CITY 30 CHARACTER - OWNER 50 CHARACTER - SURF_AREA 12 DECIMAL 2 DRAIN_AREA 14 DECIMAL 2 NORM_STOR 14 DECIMAL 2 MAX_STOR 14 DECIMAL 2 LONGITUD_X 18 DECIMAL 6 LATITUDE_Y 16 DECIMAL 6 FIPS_STATE 2 CHARACTER - FIPS_CNTY 6 CHARACTER - DESCRIPT 50 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.
NID_ID The official National Inventory of Dams identification number for the
dam, known formerly as the National Id
DAM_NAME The official name of the dam. For dams that do not have an official
name, the popular name is used
OTHER_NAME The reservoir name or names in common use other than the official name
of the dam.
HAZARD A term indicating the potential hazard to the downstream area
resulting from failure or mis-operation of the dam or facilities.
Low A dam where failure or mis-operation results in no probable
loss of human life and low economic and/or environmental loss.
Losses are principally limited to the owner's property.
Significant A dam where failure or mis-operation results in no
probable loss of human life but can cause economic loss,
environmental damage, disruption of lifeline facilities, or
impact other concerns. These dams are often located in
predominantly rural or agricultural areas but could be located
in areas with population and significant infrastructure.
High A dam where failure or mis-operation will probably cause loss
of human life.
STATE_NAME The name of the State in which the dam is located.
All records FLORIDA
COUNTY The name of the County in which the dam is located
RIVER The official name of the river or stream on which the dam is built.
If the stream is unnamed, it is identified as a tributary ("TR") to
a named river. If the dam is located offstream, the name of the river
or stream is entered plus "-OS" or "OFFSTREAM".
PRM_PURPOS A term indicating the primary purpose for which reservoir is used.
Debris Control The dam catches debris in case of flash floods.
Flood Control The dam holds water in times of high stream flow, to
protect downstream areas from flooding. The dam may normally hold a
reservoir and also have capacity for flood control, or may hold water
only for flood control.
Hydroelectric The dam holds water used for power generation.
Navigation The dam controls stream flow to allow for navigation, or
allows for navigation around an obstacle in a stream.
Other The dam meets the selection criteria for dams but is used for a
purpose other than irrigation, power generation, flood control,
navigation, water supply, recreation, fire or farm water supply,
fish & wildlife habitat, debris control, or holding tailings.
Recreation The dam holds a reservoir designed for recreational use.
Tailings The dam holds a pond containing, in aqueous form, ore and
waste materials discarded in ore-treatment processes.
Water Supply The dam holds water for domestic or commercial use.
NID_DAMTYP A term indicating the dam type as one of the following: Arch,
Buttress, Gravity.
Gravity A dam constructed of concrete and/or masonry which relies
on its weight and internal strength for stability. Includes all dams
that are not either arch or buttress dams.
Arch A concrete or masonry dam which is curved upstream so as to
transmit the major part of the water load to the abutments.
Buttress A dam consisting of a watertight part supported at intervals
on the downstream side by a series of buttresses (reinforcing structures).
YEAR_COMPL The year when the main dam structure was completed. A value of 0
indicates that the year is unknown.
NID_HEIGHT The maximum of either the dam height, the hydraulic height, or the
structural height of the dam. A value of 0 indicates that the height
is unknown.
OWN_TYPE A term indicating owner type.
Federal The dam is owned by a Federal agency.
State The dam is owned by a State or by a State agency.
NEAR_CITY The name of the nearest downstream city, town, or village that is most
likely to be affected by floods resulting from the failure of the dam.
OWNER The name of the owner of the dam.
SURF_AREA The surface area, in acres, of the impoundment at its normal retention
level.
DRAIN_AREA The drainage area of the dam in square miles. It is defined as the
area that drains to a particular point (in this case, the dam) on a
river or stream.
NORM_STOR The normal storage in acre-feet. Normal storage is the total storage
space in a reservoir below the normal retention level, including dead
and inactive storage and excluding any flood control surcharge storage.
MAX_STOR The maximum storage in acre-feet. Maximum storage is the total storage
space in a reservoir below the maximum attainable water surface elevation,
including any surcharge storage.
LONGITUD_X Dam longitude as a single value, in decimal degrees.
LATITUDE_Y Dam latitude as a single value, in decimal degrees.
FIPS_STATE The Federal Information Processing Standard (FIPS) code used by the
U.S. Bureau of the Census for the State in which the dam is located.
FIPS_CNTY The FIPS code used by the U.S. Bureau of the Census for the county in
which the dam is located
DESCRIPT FGDL added item based on Dam_name
USER NOTES:
Dam definition, from Dam Safety Act of 1972 (P.L. 92-367) and Dam Safety Act of
1986 (P.L. 99-662): Any artificial barrier, including appurtenant works, which
impounds or diverts water, and which (1) is twenty-five feet or more in height
from the natural bed of the stream or watercourse measured at the downstream toe
of the barrier, or from the lowest elevation of the outside limit of the barrier,
if it is not across a stream channel or watercourse, to the maximum water storage
elevation or (2) has an impounding capacity at maximum water storage elevation of
fifty acre-feet or more. This Act does not apply to any such barrier which is not
in excess of six feet in height, regardless of storage capacity or which has a storage
capacity at maximum water storage elevation not in excess of fifteen acre-feet,
regardless of height, unless such barrier, due to its location or other physical
characteristic, is likely to pose a significant threat to human life or property in
the event of its failure.
The information in this map layer was provided by the U.S. Army Corps of Engineers
(USACE). The original dam information came from the National Inventory of Dams (NID)
which was produced by USACE in cooperation with FEMA's National Dam Safety Program.
The full NID contains over 75,000 dams and is used to track information on the
country's water control infrastructure.
The data set was created by extracting dams 50 feet or more in height, or with a normal
storage capacity of 5,000 acre-feet or more, or with a maximum storage capacity of
25,000 acre-feet or more, from the 75,187 dams in the U.S. Army Corps of Engineers
National Inventory of Dams.
These data are intended for geographic display and analysis at the national level, and
for large regional areas. The data should be displayed and analyzed at scales
appropriate for 1:2,000,000-scale data. No responsibility is assumed by the
U.S. Geological Survey in the use of these data.
A note concerning data scale:
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:
-Reprojected data to FGDL Albers HPGN (See "Map Projection Parameters" below) -Clipped data to the State of Florida -Name changed from dams00x020 to mjdams -DESCRIPT item added based on Dam_name -Upcased all character records -Dropped old internal coverage items: DAM020G_, DAM020G_ID
REFERENCES:
United States Geological Survey U.S. Army Corps of Engineers National Atlas of the United States
DATA LINEAGE SUMMARY:
This data set was originally released in 1999 by U.S. Geological Survey. In 2001, the data was downloaded in shapefile format by the GeoPlan Center from the National Atlas website: http://nationalatlas.gov/atlasftp.html. Data was clipped from its original extent (the entire United States) to the State of Florida, and projected to FGDL Albers HPGN. When received, data was in Geographic projection, Datum: NAD83, Spheroid: GRS1980, Units: Decimal degrees.
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: Earth Science Information Center, U.S. Geological Survey
Abbr.name: USGS
Address: 507 National Center Reston, VA 20192
Phone: 1-888-275-8747
Web site: http://nationalatlas.gov/
Ftp site: ftp://crunch.tec.army.mil/NIDftp/NID1996/
Email: atlasmail@usgs.gov
Contact Person:
Phone: 703-648-4183
Email: atlasmail@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