Understanding the Data
Basemaps:
Street Map
This worldwide street map presents highway-level data for the world and street-level data for the United States,
Canada, Japan, Southern Africa, most countries in Europe, parts of Asia, Australia and New Zealand, and
parts of South America including Argentina, Brazil, Chile, and Venezuela. This comprehensive street map
includes highways, major roads, minor roads, one-way arrow indicators, railways, water features, administrative
boundaries, cities, parks, and landmarks, overlaid on shaded relief imagery for added context. The map also includes building footprints for selected areas in the United States and Europe. The street map was
developed by ESRI using ESRI basemap data, DeLorme basemap layers, and road data, USGS elevation data,
Intact Forest Landscapes data for the world; NAVTEQ data for Australia, New Zealand, and South America
(Argentina, Brazil, Chile, Venezuela); and TomTom Dynamap® and Multinet® street data for North America and
Europe.
Aerial Photography
This map presents low-resolution imagery for the world and high-resolution imagery for the United States and other
areas around the world. The map includes NASA Blue Marble: Next Generation 500m resolution imagery at small
scales (above 1:1,000,000), i-cubed 15m eSAT imagery at medium-to-large scales (down to 1:70,000) for the
world. The map features i-cubed Nationwide Prime 1m or better
resolution imagery for the contiguous United States. i-cubed Nationwide Prime is a seamless, color mosaic of
various commercial and government
imagery sources, including Aerials Express 0.3 to 0.6m resolution imagery for metropolitan areas and the
best available United States Department of Agriculture (USDA) National Agriculture Imagery Program (NAIP)
imagery and enhanced versions of United States Geological Survey (USGS) Digital Ortho Quarter Quad (DOQQ)
imagery for other areas. For more information on this map, visit us online at
https://goto.arcgisonline.com/maps/World_Imagery. Dates for the images vary, but can be found under the "Metadata, Content Viewer" description.
Topographic Maps
This map presents land cover imagery for the world and detailed topographic maps for the United States. The map
includes the National Park Service (NPS) Natural Earth physical map at 1.24km per pixel for the world at
small scales, i-cubed eTOPO 1:250,000-scale maps for the contiguous United States at medium scales, and
National Geographic TOPO! 1:100,000 and 1:24,000-scale maps (1:250,000 and 1:63,000 in Alaska) for the
United States at large scales. The TOPO! maps are seamless, scanned images of United States Geological
Survey (USGS) paper topographic maps. For more information on this map, visit us online at
https://goto.arcgisonline.com/maps/USA_Topo_Maps.
Water Availability:
Water Availability Basin
Water availability is the amount of water that can be appropriated from a given point on a given
stream for new out-of-stream consumptive uses. It is obtained from the natural stream flow
by subtracting existing in-stream flow requirements and out-of-stream consumptive uses. For a
detailed description of the Water Availability Report program and the methodology used to
develop it, you may review the report titled
Determining Water Availability in Oregon.
For additional information, please visit
Water Availability Report System.
Ideally a water availability calculation would be
done for every watershed associated with a
point of diversion or an in-stream water right.
A watershed, in this case, includes all lands draining
to the stream upstream of the point of diversion or the
downstream end of an in-stream water right reach.
Because there are so many water rights, the
ideal approach is impractical.
The practical alternative is to limit the number of
watersheds for which water availability is calculated.
The delineation of these watersheds depends
on the location of in-stream demands and
on the physiography of affected streams. Generally
watersheds are defined above the mouths
of significant tributaries, on main channels
above significant tributaries and for all in-stream
demands.
These delineated watersheds are referred to as
Water Availability Basins (WABs). Water availability
is estimated at the downstream end, or
pour point, of each WAB.
Large drainage areas( e.g. the Rogue and
Umpqua basins) are broken into a number of
WABs. The WABs are nested, each upstream
WAB being included in a WAB downstream. For
water to be available in a given WAB, it must be
available in all the other watersheds in which it is
nested.
Priority WABS
OWRD and the Department of Fish and Wildlife jointly identified
priority areas for streamflow restoration in basins throughout the state. These priority areas
represent watersheds in which there is a combination of need and opportunity for flow
restoration to support fish recovery efforts under the Oregon Plan for Salmon and Watersheds.
OWRD is focusing its efforts under the Oregon Plan on these priority areas.
Observation Wells:
Current state observation wells are maintained by the Oregon Water Resources Department. These wells are used to monitor the
health of Oregon's aquifers and are fitted with water-level recording devices. OWRD staff revisit these wells several times
throughout the year.
Gaging Stations:
The Water Resources Department operates more than 200 stream and reservoir gages throughout the
state. More than 160 of these gages are operated as near real-time. These gages transmit stream data
once an hour. The data is received and downloaded to the Department’s database where it is
processed and updated on the web page every hour. In addition,
information from another 225 gages operated by the USGS and other agencies is also shared on the
Department’s website.
Visit the Near Real Time Hydrographics Data website.
Significant Points of Diversion (SIG PODs):
The Oregon Water Resources Department is responsible for implementing the Water
Resource Commission’s 2000 Water-Use Measurement Strategy. The strategy directs the
Department to focus limited resources on significant points of diversion in high priority
watersheds. The Department has identified over 2300 such points and is working with
landowners on installing measurement devices.
PODs by Source Type
Representation of points of diversion by source type of reserviors, sumps, springs, streams and wells. Other source types are not mapped in this theme.
Hydrography:
Gaging Stations
The Water Resources Department operates more than 200 stream and reservoir gages throughout the
state. More than 160 of these gages are operated as near real-time. These gages transmit stream data
once an hour. The data is received and downloaded to the Department’s database where it is
processed and updated on the web page every hour. In addition,
information from another 225 gages operated by the USGS and other agencies is also shared on the
Department’s website.
Visit the Near Real Time Hydrographics Data website.
OWRD Streams
The primary objective of the OWRD stream code system was to assign index code numbers and develope mileage
figures for all streams in the State of Oregon. This involved, in a sense, a re-naming of all streams
using a system of code numbers and mileages which would allow precisely located data input. The
code will provide information which the computer will require to identify
specific points, reaches of streams or drainage areas.
The OWRD stream code is used throughout OWRD as a way to uniquely identify each stream.
River Miles
River miles are approximate and are computer generated.
PLSS:
Townships/Sections
The Public Land Survey System (PLSS) is a way of subdividing and describing land in the United States.
All lands in the public domain are subject to subdivision by this rectangular system of surveys, which is
regulated by the U.S. Department of the Interior, Bureau of Land Management (BLM).