77-16 164 street, 3rd Floor, Fresh Meadows, NY 11366
+1 (631) 930-3292

Optical Monitoring

An optical monitoring survey is a type of land survey that uses specialized equipment to measure the displacement, deformation, or movement of structures, buildings, or other features on the land surface over time. This type of survey can be used to monitor changes in the land that may be caused by a variety of factors, such as subsidence, landslides, erosion, or changes in water levels.

Optical monitoring surveys typically use a combination of survey-grade total stations, levels, and/or GPS receivers and cameras or other optical devices to measure changes in the position of features on the ground. The surveyor will establish a series of control points, which are used as references to monitor changes in position over time. The surveyor will then return to these points at regular intervals to collect additional data, and using specialized software, the data will be compared over time, showing the movement or deformation of the structure or land surface.

Optical monitoring surveys can be used in a variety of applications such as, but not limited to:

  • Monitoring the stability of buildings, bridges, dams, and other structures
  • Monitoring the movement of landslides, subsidence, or other types of ground movement
  • Monitoring the impact of mining or other subsurface excavation on the stability of the surface
  • Monitoring the impact of changes in water levels on coastal structures or shorelines.

In New York and other areas, these types of survey are used by engineers, geologists, environmental consultants, and other professionals to provide detailed and accurate information about the stability and movement of structures and land surfaces over time. This information can be used to identify potential hazards,


New York City has specific requirements for optical monitoring surveys, as part of its efforts to ensure the safety and structural integrity of buildings and other structures in the city.

The New York City Department of Buildings (DOB) and the Department of Transportation (DOT) have regulations that require certain types of buildings, structures, and sites to be periodically monitored for movement or deformation. This includes buildings that are at risk for collapse or damage, such as those that are located in areas of known soil instability, or those that are located near underground subway or subway ventilation structures, etc.

For example, the DOB has special requirements for buildings that are located in areas of known soil instability. These buildings must be periodically monitored by a licensed land surveyor or engineer, who must submit a report to the DOB that includes the results of the monitoring and any recommendations for repairs or other actions that may be necessary to maintain the safety of the building.

Similarly, the DOT regulations require that certain types of structures, including bridges, retaining walls, and other transportation infrastructure, must be regularly monitored to ensure they are safe and stable. Monitoring must be performed by an engineer or other professional who is registered with the DOB, who must submit a report that includes the results of the monitoring and any recommendations for repairs or other actions.

Overall, NYC has strict requirements for optical monitoring surveys, as it aims to ensure the safety and stability of its buildings and infrastructure, and protect the public safety. Compliance with these regulations is mandatory, and any work or inspections related to optical monitoring surveys must be performed by qualified professionals who are licensed