Benchmarks | ||||||
|---|---|---|---|---|---|---|
| Category | Survey | |||||
| Feature Dataset Name | STAND-ALONE | |||||
| Item Name | BENCHMARK_PDX | |||||
| Database Type | SDE | |||||
| Originator | City of Portland | |||||
| Bureau | Bureau of Transportation | |||||
| Publication Date | ||||||
| Abstract | Benchmarks are survey markers that provide a point of particular elevation used as a reference for determining elevations of other points in a survey. They are used by surveyors, engineers, planners, and contractors for establishing elevations for planning, designing, and/or construction of various projects.The City of Portland is responsible for establishing and maintaining a network of benchmarks throughout the city, each having a known elevation expressed in feet in the City of Portland’s own datum (established in 1896). Most of the City of Portland’s Benchmarks are brass disks about 2 ½" in diameter, and all are marked "City of Portland Bench Mark No. nnnn " and usually set in the curbs of streets. Occasionally you’ll see larger disks of 3 ¾" diameter which are "Class A" monuments, and some benchmarks are set in retaining walls, bridge wing walls, culvert headwalls, concrete steps, or wherever the most stable and accessible placement was determined to be for a specific location. You might also see benchmarks similar to those of the City of Portland’s but with another governmental agency’s or private firm’s name stamped on it. Occasionally the City of Portland Benchmark Book will refer to these monuments and provide elevations, but more often you’ll have to contact the appropriate institution for more information. The benchmark numbers the City assigned to outside agency monuments are for indexing purposes only; PDOT does not stamp a City of Portland benchmark number on other agencies' monuments. | |||||
| Purpose | For mapping and analysis related to the maintenance of survey benchmarks. | |||||
| Supplemental Information | https://www.portlandoregon.gov/transportation/35705 | |||||
| Last Dataset Update | 12/13/2024 19:32 | |||||
| Last Source Update | 12/13/2024 05:20 | |||||
| Maintenance/Update Frequency | As needed | |||||
| Extent | Clackamas County, Multnomah County, and Washington County, Oregon | |||||
| Data Type | Vector | |||||
| Shape Type | Point | |||||
| Feature Count | 4724 | |||||
| Horizontal Position Accuracy | ||||||
| Horizontal Position Accuracy Link | Taxlots | |||||
| Progress | Complete | |||||
| North Bounding Coordinate | 731143.068149576 | |||||
| South Bounding Coordinate | 640272.149116654 | |||||
| East Bounding Coordinate | 7778705.13539197 | |||||
| West Bounding Coordinate | 7603755.81817182 | |||||
| Theme Keyword(s) | transportation,survey, benchmarks, elevation | |||||
| Theme Keyword Thesaurus | None | |||||
| Place Keyword(s) | Portland, Multnomah County, Washington County, Clackamas County, Oregon | |||||
| Place Keyword Thesaurus | None | |||||
| Access Constraints | Available for Public Use | |||||
| Use Constraints | These data are distributed under the terms of the City of Portland Data Distribution Policy. Care was taken in the creation of this data but it is provided "as is". The City of Portland cannot accept any responsibility for errors, omissions, or positional accuracy. | |||||
| Source Dataset Type | Enterprise Geodatabase | |||||
| Output Geodatabase | ASSETS_PDOT | |||||
| Distribution | Grid: State plane coordinate system 1983(91). Units: International feet Datum: North American Datum of 1983/1991 (HPGN) Liability: The information in this file was derived from digital databases on the City of Portland GIS. Care was taken in the creation of this file. The City cannot accept any responsibility for errors, omissions, or positional accuracy. There are no warranties, expressed or implied. Format: Shapefile or File Geodatabase Feature Class - Data will be provided via City of Portland FTP Site. Online Resource: http://portlandmaps.com/opendata Online Instructions: City of Portland Public/Open Data is distributed via the PortlandMaps Open Data Site - http://portlandmaps.com/opendata. Data not available on the PortlandMaps Open Data site can be requested by contacting the City of Portland CGIS Group - maps@portlandoregon.gov Transfer Size: varies SPCS Zone Identifier: 5076 | |||||
| Contact(s) | ||||||
| ||||||
| File(s) | ||||||
| Images |
| |||||
| Lineage | ||||||
Web Services
| Service | Description | Feature Access | Layer |
|---|---|---|---|
| Transportation | Transportation Layers | Dynamic | Survey Benchmarks |
Attribute Tables & Domains
| | ||||||
|---|---|---|---|---|---|---|
| Table Description | ||||||
| Table Jurisdiction | ||||||
| Column Sort | Column Name | Column Alias | Column Type | Column Size | Domain Value(s) | Column Description | 1 | BMNum | BMNum | Integer | 4 | | | 1 | BMStatus | BMStatus | String | 10 | | | 1 | BMElevation | BMElevation | Numeric | 8 | | | 1 | BMDescription | BMDescription | String | 150 | | | 1 | District | District | String | 3 | | | 1 | Street1 | Street1 | String | 50 | | | 1 | Street2 | Street2 | String | 50 | | | 1 | AVAddress | AVAddress | String | 50 | | | 1 | AVStatus | AVStatus | String | 1 | | | 1 | AVScore | AVScore | Integer | 2 | | | 1 | AVSide | AVSide | String | 1 | | | 1 | QS1A | QS1A | Integer | 4 | | | 1 | QS1B | QS1B | String | 10 | | | 1 | QS2 | QS2 | String | 4 | | | 1 | QS3 | QS3 | Integer | 4 | | | 1 | QS4 | QS4 | Integer | 4 | | | 1 | DateInventoried | DateInventoried | Date | 36 | | | 1 | Northing | Northing | Numeric | 8 | | | 1 | Easting | Easting | Numeric | 8 | | | 1 | DateLastChangedOn | DateLastChangedOn | Date | 36 | | |