| Item |
Item Description |
| OBJECTID |
Internal feature number.
|
| Shape |
The representation of the entity in the data.
Point = 0-dimensional element
|
|
| Dams00x020 |
Internal feature number.
|
| Dam_name |
The official name of the dam. For dams that do not have an official
name, the popular name is used.
<blank> = The name of the dam is not provided in the National Inventory of
Dams.
|
|
| Other_name |
The reservoir name or names in common use other than the official name
of the dam. Names are separated with semicolons.
<blank> = There are no other names for the dam, or the other names are
unknown.
|
|
| Nidid |
The official National Inventory of Dams identification number for the
dam, known formerly as the National Id. The first two characters of the
identity are the State two letter abbreviation, based on the location of
the dam. The last five characters of the identity are a unique number
(AB#####).
|
| Longitude |
Dam longitude as a single value, in decimal degrees.
|
| Latitude |
Dam latitude as a single value, in decimal degrees.
|
| County |
The name of the county in which the dam is located. If the dam falls in
more than one county, the names may be separated by a slash, a comma, or
a semicolon.
<blank> = The name of the county is not provided in the National Inventory of
Dams.
|
|
| 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".
<blank> = The name of the river is not provided in the National Inventory of
Dams.
|
|
| City |
The name of the nearest city, town, or village that is most likely to be
affected by floods resulting from the failure of the dam.
<blank> = The name of the city is not provided in the National Inventory of
Dams.
|
|
| Own_name |
The name of the owner of the dam.
<blank> = The name of the owner is not provided in the National Inventory of
Dams.
|
|
| Own_type |
A term indicating owner type.
<blank> = The owner type is unknown.
F = The dam is owned by a Federal agency.
L = The dam is owned by a County, City, Regional, or other similar local
government or government agency.
P = The dam is owned by an individual or individuals, or by a private
company.
S = The dam is owned by a State or by a State agency.
U = The dam is owned by a public utility.
|
|
| Dam_type |
A code or codes indicating the dam type, in order of importance. Codes
are concatenated if the dam is a combination of several types. For
example, CNCB would indicate a concrete buttress type dam.
<blank> = The dam type is unknown.
CB = Buttress
CN = Concrete
ER = Rockfill
MS = Masonry
MV (or MultiArch) = Multi-arch
OT = Other
PG = Gravity
RE = Earth
ST = Stone
TC = Timber crib
VA = Arch
|
|
| Purposes |
A code or codes indicating the purposes for which reservoir is used, in
order of importance. The codes are concatenated if the dam has multiple
purposes. For example, SCR would indicate the primary purposes of Water
Supply and Flood Control and Storm Water Management, followed by
Recreation. The data may contain words or abbreviations that were used
instead of the appropriate codes; these have been retained.
<blank> = The purpose of the dam is not provided in the National Inventory of
Dams.
C = Flood control and storm water management
D = Debris control
F = Fish and wildlife pond
H = Hydroelectric
I = Irrigation
N = Navigation
O = Other
P = Fire protection, stock, or small farm pond
R = Recreation
S = Water supply
T = Tailings
|
|
| Yr_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 vertical distance between the
lowest point on the crest of the dam and the lowest point in the
original streambed), the hydraulic height (the vertical distance between
the maximum designed water level and the lowest point in the original
streambed), or the structural height (the vertical distance between the
lowest point of the excavated foundation and the top of the dam) of the
dam. The height is given in feet, to the nearest foot.
0.00000000000 = The height is unknown.
|
|
| 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.
0.00000000000 = The maximum storage is unknown.
|
|
| Normal_sto |
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.
A value of 0 may indicate that the normal storage is unknown or may
indicate that the dam is normally dry.
|
| Surf_area |
The surface area, in acres, of the impoundment at its normal retention
level.
0.00000000000 = The surface area is unknown.
|
|
| 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.
0.00000000000 = The drainage area is unknown.
|
|
| Hazard |
A term indicating the potential hazard to the downstream area resulting
from failure or mis-operation of the dam or facilities.
L = The potential hazard is low. A dam where failure or misoperation
results in no probable loss of human life and low economic and/or
environmental loss. Losses are principally limited to the owner's
property.
S = The potential hazard is significant. A dam where failure or
misoperation 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.
H = The potential hazard is high. A dam where failure or misoperation
will probably cause loss of human life.
U = The potential hazard is unknown.
|
|
| State |
The two letter abbreviation for the State in which the dam is located.
|
| Symbol |
A code indicating how the dam is symbolized in the National Atlas Map Maker.
The symbol is determined from the primary Purpose code given for the dam,
which is the first or only code listed under the attribute Purpose. Where
the Purpose attribute contains a word or abbreviation instead of the
appropriate code, the first letter of the Purpose value was still used to
determine the symbol code. In these cases the symbol may not accurately
represent the true primary purpose of the dam.
<blank> = The dam has an unknown purpose.
C = The dam is for flood control and storm water management.
D = The dam is for debris control.
F = The dam contains a fish and wildlife pond.
H = The dam is for hydroelectric power.
I = The reservoir contained by the dam is for irrigation.
N = The dam is for navigation.
O = The dam or reservoir contained by the dam has a primary purpose other
than flood control and storm water management; debris control; fish and
wildlife pond; hydroelectric; irrigation; navigation; fire protection,
stock, or small farm pond; recreation; water supply; or tailings
P = The dam contains a fire protection, stock, or small farm pond
R = The reservoir contained by the dam is for recreation.
S = The reservoir contained by the dam is for water supply.
T = The dam contains a tailings pond.
|
|
| DESCRIPT |
FGDL added field based on DAM_NAME
|
| FGDLAQDATE |
The date FGDL acquired the data from the source.
|
| AUTOID |
Unique ID added by GeoPlan
|
In the online National Atlas of the United States Map Maker, at scales
smaller than 1:4,850,000 the data is thinned for display purposes. For
scales between 1: 4,850,000 and 1:22,000,000, dams are only shown if they
have a height of 500 feet or more, or a normal storage capacity of 50,000
acre-feet or more, or a maximum storage capacity of 250,000 acre-feet or
more (1280 dams). At scales smaller than 1:22,000,000, dams are only
shown if they have a height of 5000 feet or more, or a normal storage
capacity of 500,000 acre-feet or more, or a maximum storage capacity of
2,500,000 acre-feet or more (290 dams).
The National Inventory of Dams (NID) is a collection of information about
dams in the United States and its territories, produced by the U.S. Army
Corps of Engineers (USACE). The USACE works closely with the Association
of State Dam Safety Officials (ASDSO), the Federal Emergency Management
Agency, and other State and Federal agencies to update and publish the NID.
The National Inventory of Dams contains more than 79,000 dams, provided
voluntarily by a wide variety of agencies. This information is used to track
information on the country's water control infrastructure and to allocate Federal
resources for dam safety programs.
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.
|