Geodetic Station Markers
Formerly Federal-aid Policy Guide Non-Regulatory Supplement NS 23 CFR, Part 630D,
December 9, 1991, Transmittal 1
See Order 1321.1C FHWA Directives Management
- Authority. Section 101(a), Title 23, United States Code (U.S.C.), defines the term "construction" to include the establishment of temporary and permanent geodetic markers in accordance with specifications of the National Oceanic and Atmospheric Administration (NOAA) in the Department of Commerce. Section 315, Title 23, U.S.C. and 49 CFR 1.48 authorize the issuance of regulations to implement these projects.
- Background (No CFR paragraph reference)
- The National Ocean Survey (NOS), a component of NOAA, has the responsibility for establishing a network of basic control surveys and station markers of sufficient accuracy and permanence to provide the rigid framework needed by engineering, cadastral and cartographic agencies. Adequately monumented second-order geodetic surveys are needed to provide the necessary horizontal and vertical control for the aerial and ground surveys and mapping activities required in the development and operation of modern highways.
- The Office of Management and Budget has delegated to the Department of Commerce the leadership in ensuring that Federal funds for high-order surveying are expended in such a manner that they contribute to the completion of the National Geodetic Control Networks and are not per formed as single purpose surveys. This responsibility has been further delegated to NOS and its subcomponent, the National Geodetic Survey.
- Policy (23 CFR 630.402)
- It shall be the policy of the Federal Highway Administration (FHWA) to encourage the use of the procedures described herein to establish permanent survey control of second-order accuracy, or better, whenever feasible or practicable for highway development.
- Geodetic surveys may be performed by NOS forces or by qualified crews assigned by the State highway department. A State highway department should feel free to do the work with its own forces, but if it does not have personnel on its staff qualified to undertake the work, it may employ either qualified private firms or NOS if that agency's services can be secured.
- Geodetic station marker projects may be established to aid in the development of any Federal-aid route. Extensive projects covering routes that will result in a pattern of closed geometric figures are encouraged. This is especially desirable as a means of increasing the reliability of the survey where few existing markers are available for checking the accuracy of surveys.
- Modern surveying instruments and methods provide a means of establishing a considerable number of geodetic station markers on adjacent routes by developing auxiliary control stations. Consideration, therefore, should be given to establishing some geodetic station markers to serve as control points on routes nearby or connecting to the Federal-aid routes covered by geodetic survey projects when this can be done as an incidental to the main project with little additional cost.
- Initiation of Projects (23 CFR 630.403). Any State highway or transportation department desiring to initiate a project for the establishment of geodetic station markers, either as a planning survey project or as a Federal-aid construction project, should first write to the Director, National Geodetic Survey, Rockville, Maryland 20852. The Director will arrange for a representative to meet with representatives of the State and the FHWA Division Administrator to discuss the proposed project. At this meeting a decision should be reached on such things as (a) the means by which the survey project will be accomplished; (b) the spacing between markers; (c) whether the State will furnish aerial photographs on which the location of markers will be indicated; (d) the approximate schedule to be followed; and, (e) the approximate cost of the project, which shall include all station markers, their setting and surveying, and the computations and adjustments of the survey. The agreement between the State and NOS resulting from this meeting should be made a part of the project record. The NOS will be custodians of and the distributing agency for the survey data.
- Standards (23 CFR 630.404). In the execution of surveys for establishing geodetic station markers, it may be necessary to establish temporary intermediate geodetic stations. If these intermediate stations have a potential value for extending or checking other future highway surveys or would be of benefit to other survey agencies, they should be preserved by setting permanent station markers, where needed, and preserving the necessary data.
- Programming (No CFR paragraph reference)
- Federal-aid construction projects for the establishment of geodetic station markers should be programmed in the same manner as other Federal-aid projects. Projects in each State shall be identified by a separate numbering system in chronological order beginning with number one. A separate symbol designation of GM will be used, followed by the letter indicating the class of funds, such as GMI, GMF, and so forth. The ratio of Federal participation will be that authorized for the class of funds applicable to the Federal-aid system involved.
- Projects for the establishment of geodetic station markers may be included in HPR work programs provided that regular necessary planning activities can be maintained otherwise. On such work programs, geodetic station marker projects will be included as separate items.
- Preservation (No CFR paragraph reference)
- Any loss or destruction of permanent monuments necessitates additional expenditure of public funds and deprives engineers of much valuable data until they are replaced.
- It is recognized that some station markers may be in such locations or placed in such a manner as to interfere with future highway construction or maintenance. When such situations occur, advice should be forwarded to the Director, National Geodetic Survey, Rockville, Maryland 20852, telephone 301-496-8600, who will take corrective measures or arrange with other agencies for this service. Surveying and mapping agencies have given assurance that they will, to the best of their ability, relocate the monuments with their own forces. When this cannot be accomplished readily, they would appreciate cooperation of State highway officials or contractors to ensure that the basic data is preserved until such time as the new monuments can be established.