ArcGIS REST Services Directory
JSON

Survey_Benchmarks (FeatureServer)

View In:   Map Viewer

Service Description: Point layer depicting locations of Survey Benchmarks in the City of Long Beach

Service ItemId: 1f809519baf244359fa3fb9097fd3961

Has Versioned Data: false

Max Record Count: 2000

Supported query Formats: JSON

Supports applyEdits with GlobalIds: False

Supports Shared Templates: True

All Layers and Tables

Layers:

Description:
This data set depicts the estimated horizontal locations of some 1,700 + City of Long Beach Survey Benchmarks. A survey benchmark is a permanent marker established by a land surveyor to provide elevation reference to a defined vertical datum. More precise locations are provided in the descriptions of the individual benchmarks contained within the Survey Benchmark Book published on the City website (longbeach.gov/pw/resources/maps/). 

The elevations shown therein are based upon measurements made through conventional differential leveling methods. The latest comprehensive inventory, measurement and adjustment of citywide benchmarks was made in 1985. The network is referenced to the National Geodetic Vertical Datum of 1929 (NGVD29) and is based upon an elevation of +11.129 feet on the tidal benchmark named “Tidal 8” located at Berth 69 of Municipal Pier No.1 in the Los Angeles Outer Harbor. 
 
The intention of the benchmark list is to provide vertical elevation data to the public on city-maintained benchmarks. As with all survey data, care should be taken to verify the benchmark elevations by measuring multiple benchmarks. The horizontal locations contained in the data set are only approximate and intended exclusively for geographical representation for project planning purposes. 

Please report any inconsistencies in this data to the Surveying department at the City of Long Beach by phone at (562)570-3093 or by email at CLBSurvey@longbeach.gov.

For more information, see Surveying Practice - California Business & Professions Code, Chapter 15; Article 5; Section 8771.”



Copyright Text: City of Long Beach, CA

Spatial Reference: PROJCS["NAD_1983_StatePlane_California_V_FIPS_0405_Feet",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Lambert_Conformal_Conic"],PARAMETER["False_Easting",6561666.667],PARAMETER["False_Northing",1640416.667],PARAMETER["Central_Meridian",-118.0],PARAMETER["Standard_Parallel_1",34.03333333333333],PARAMETER["Standard_Parallel_2",35.46666666666667],PARAMETER["Latitude_Of_Origin",33.5],UNIT["Foot_US",0.3048006096012192]]

Initial Extent:
Full Extent:
Units: esriFeet

Child Resources:   Info   SharedTemplates

Supported Operations:   Query   ConvertFormat   Get Estimates