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Oregon Coordinate Reference System Standard
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Article Content
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| Oregon Lambert |
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Ten different major map projections have been commonly used in Oregon, and all have varied error across the state. A common projection for data display, analysis, publishing and transfer is needed. The Oregon Geographic Information Council (OGIC) endorsed the use of Oregon Lambert as a standard for state agencies.
Oregon Lambert is recognized by the European Petroleum Survey Group (EPSG) which maintains and publishes an international coordinate reference system database. The EPSG spatial reference ID for Oregon Lambert is 2992.
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Total area error for the state is 0.0045% (2,900 acres out of 64 million).
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Average length error for the state is 0.0176% (1.76 in 10,000).
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Error in distance measurement may be as high as 0.053% (5.3 in 10,000).
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| COORDINATE REFERENCE SYSTEM DESCRIPTION |
Projection
| LAMBERT CONIC CONFORMAL
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Datum
| NAD83
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Units
| INTERNATIONAL FEET, 3.28084
(.3048 Meters)
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Spheroid
| GRS1980
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Parameters
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1st Standard Parallel
| 43 00 0.000
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2nd Standard Parallel
| 45 30 0.000
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Central Meridian
| -120 30 0.000
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Latitude of Projection's Origin
| 41 45 0.000
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False Easting
| 400,000.00000 Meters
(1,312,335.958 Feet)
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False Northing
| 0.00000 Meters
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Notes: US Survey foot = 1200/3937 meters (0.3048006096 m)
International foot = 0.3048 m exactly, 1 meter = 3.28084 Intl. feet
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| Oregon Lambert History |
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| Oregon GIS Program Leaders (GPL) formed a committee to evaluate and recommend a common projection for data display, analysis, publishing and transfer for Oregon. The committee was comprised of representatives from the DAS/IRMD Geospatial Enterprise Office (SSCGIS), the Oregon Department of Transportation (ODOT), the Oregon Department of Forestry (ODF), the Oregon Department of Environmental Quality (DEQ), and the Oregon Department of Geology and Mineral Industries (DOGAMI). | Additionally, other organizations within the state were consulted. The committee reviewed projections in use, compared how neighboring states deal with similar issues, and calculated projection errors. They submitted a recommended standard, Oregon Lambert, to the Oregon Geographic Information Council (OGIC) who endorsed the standard for use by state agencies. |
Recommendations:
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Projection metadata accompany all spatial data transfers for Oregon agencies.
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Spatial data published by Oregon agencies use the adopted standard, Oregon Lambert.
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| Oregon Lambert Methodology |
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The total change in latitude for the state was calculated and then the standard parallels were set at 1/6th of the change north of the minimum and 1/6th of the change south of the maximum. The final values for the standard parallels were rounded to even or half degrees. The central meridian was set at 120 degrees 30', the mid point east to west of the state. The origin was shifted 400,000 meters to the west to put the entire state in the positive quadrant.
Error statistics (pdf)
Minimum, maximum, and mean percentage errors for each map projection. | Images Showing Calculated Percentage Error
These maps were created from error statistic calculations based on formulas in Map Projections- A Working Manual by John Snyder, USGS Professional Paper 1385, 1987. Each "cell" is a 7.5' USGS quad.
Polygon error (gif) Oregon Lambert, NAD83, Intl. Ft
Polygon error (gif) US Lambert, NAD27, Meters
Length error (gif) US Lambert, NAD27, Meters
Polygon error (gif) State Plane North Zone, NAD83, Intl. Ft
Length error (gif) State Plane North Zone, NAD83, Intl. Ft
Length error (gif) UTM Zone 10, NAD83, Meters
Polygon error (gif) Oregon Albers, NAD83, Meters
Length error (gif) Oregon Albers, NAD83, Meters
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