Control Surveys

Providing Engineering Surveys and Land Surveys to support the planning, design, and construction of transportation projects.

Control Surveys

Control points and networks established by Control Surveys provide precise positioning on the surface of the earth and are utilized to orient and reference the subsequent Engineering Surveys and Land Surveys.  This is essential to coordinate the planning and construction of transportation projects for a corridor over multi-year periods.

Control Surveys are typically separated into horizontal control (GPS) and vertical (elevation) control.  A record of horizontal and vertical control monuments established along project corridors is maintained by ARDOT in Microsoft Access databases, and is available for download at the link below.  The horizontal control (GPS Points) has also been added as a layer to the Surveyor’s Map maintained by the Division of Land Surveys of the Arkansas Geographic Information System’s Office.

ARDOT GPS & BM’s – MS Access Database of ARDOT GPS & BM’s in Compressed ZIP Format (Updated May. 2023)

ARDOT GPS & BM’s – PDFs of ARDOT GPS & BM’s in Compressed ZIP Format (Updated May. 2023)


ARDOT, and its partners, maintain a network of Global Navigation Satellite System (GNSS) Continuously Operating Reference Stations (CORS).  This provides the infrastructure for ARDOT’s statewide control network and is aligned with the National Geodetic Survey (NGS) National Spatial Reference System (NSRS).  Real-time GNSS corrections are currently being broadcast from this network, for more information please visit

The ARDOT CORS network currently consists of the stations listed below.  Links are provided to the NGS website to retrieve data for stations published with NGS.  Files and data for the stations not published with NGS may be obtained by utilizing the Reference Data Shop at If you need help navigating the webpage, email for assistance.

NGS Horizontal and Vertical Control

Information related horizontal and vertical control marks established by NGS may be found at

Efforts to expand and densify ARDOT’s horizontal and vertical control network have been coordinated with NGS Central Plains Advisor, Brian Ward, to ensure consistency and alignment of the State network with the NSRS.  Through the Regional Advisor, NGS has provided training and guidance in establishing new horizontal and vertical control marks so that they may be published with NGS as part of the NSRS.  The NGS Central Plains Regional Advisor may be contacted at