20230213 17413800 1.0 TRUE Joe Gordon Metro Data Resource Center 503-797-1587 503-797-1909 600 NE Grand Ave. Portland OR 97232 joe.gordon@oregonmetro.gov 20230201 ArcGIS Metadata 1.0 Metro Data Resource Center 503 797-1742 503 797-1909 600 NE Grand Ave. Portland OR 97232 drc@oregonmetro.gov No cost Shapefile 146 146 http://www.oregonmetro.gov/rlisdiscovery Email drc@oregonmetro.gov or call 503-797-1742 for further instructions. Contours (five ft. interval) 2002-01-31 Metro Data Resource Center Created as a by-product of the 2001 digital ortho-rectified imagery. Covers Portland metropolitan area (511 sq. mi.). Metro's contactor was Triathlon, Inc., 13800 Commerce Parkway, Richmond BC V6V 2J3. Contact is Shirley McLaren, 604 233-5045, smclaren@triathloninc.com. Copyright 2001 by Metro. Date of last data update: 2021-09-06 This is official RLIS data. Contact Person: Joe Gordon joe.gordon@oregonmetro.gov 503-797-1587 RLIS Metadata Viewer: <a href='https://gis.oregonmetro.gov/rlis-metadata/#/details/1856' rel='nofollow ugc'>https://gis.oregonmetro.gov/rlis-metadata/#/details/1856</a> RLIS Terms of Use: <a href='https://rlisdiscovery.oregonmetro.gov/pages/terms-of-use' rel='nofollow ugc'>https://rlisdiscovery.oregonmetro.gov/pages/terms-of-use</a> The orthophotography is collected annually for creating the Metro vacant land layer. The vacant layer is a major component in the buildable land inventory. The photos are also used in many of the region's GIS systems as a base layer. A consortium of local governments purchased this imagery. These contours are useful when USGS contours do not show sufficient detail. http://library.oregonmetro.gov/rlisdiscovery/browse_graphic/contours_5.png 5 ft contour lines in blue on a gray basemap of the region for orientation. PNG Portland Multnomah County Washington County Clackamas County Oregon Contour topography elevation hypsography contour line RLISContourtopographyelevationhypsographycontour linePortlandMultnomah CountyWashington CountyClackamas CountyOregon This database and GIS data are made available under the RLIS Open Database End User License Agreement. See https://rlisdiscovery.oregonmetro.gov/pages/open-database-license. The information in this file was derived from digital databases on Metro's GIS. Care was taken in the creation of this file. Metro cannot accept any responsibility for errors, omissions, or positional accuracy. There are no warranties, expressed or implied. true -123.153528597 -122.367487422 45.70263875 45.23396470 Ground condition 2021-09-06 Control: Contractor established 20 exterior ground control points around the perimeter of the project area. In addition, eight points were used in the interior of the project area. These points were targeted prior to the photo mission with positional and elevation data collected for each point to an accuracy of +/- 4 inches. Vertical Datum: Orthometric NAVD88 (in international feet). Photography: Date of acquisition: July 23, 25, 26, 2001 Film: Kodak Aerocolor III Negative Film 2444 Negative scale: 1"=1,600'' Format: 9"x9" aerial mapping format Altitude: Approx. 9,600 feet Exposure: Each exposure covers about 4 sq. mi. and the camera system used precision airborne GPS equipment. Conditions: ClearFocal length: 6". Aerial triangulation: Contractor used analytical aerial triangulation (AT), using established photogrammetric procedures, to establish a dense secondary network of control points throughout the project area. Digital terrain model: Contractor collected major surface features as breaklines in preparation for the contour generation process. All DTM collection was carried out on SSK softcopy workstations using Contractor''s proprietary softcopy collection software, Virtual Mapping Software (VMS). From the DTM a Triangulated Irregular Network or TIN surface was generated. The TIN surface was made up of triangles composed of vertices defined by the masspoints as well as breaklines. No triangle was allowed to cross a breakline, thus ensuring that the form of the TIN surface captured any sudden changes in the terrain surface. The TIN surface is suitable for generating contours at regular intervals of 5 feet, with a vertical accuracy that can be expressed as "90% of the 5 foot contours are accurate to within 2.5 foot in areas of open, un-obscured ground." This meets the NMAS specification for mapping at 1"=200'' Changed native SDE storage precision from low to high 2010-01-22 Contours_5.dbf Contour attribute table Elevation Elevation in feet NA Subset Intervals of feet - 10, 20, 50 and 100 NA