• LinkedIn
  • Twitter
  • Instagram
  • Facebook
 
USA  
 
 

Capitol Region Council of Governments

The Capitol Region Council of Governments (CRCOG) consists of leading elected officials working for 29 municipalities in the Greater Hartford area. CRCOG members have been working together for 30 years to improve efficiency and save money by making bundled purchases of goods and services. CRCOG submitted and was awarded a grant to help improve information to be used for GIS applications.

Bullet Digital Orthophotography
Bullet GPS Survey
Bullet LiDAR
 
 

WSP USA provided high resolution color digital orthophotography at 0.25’ pixel resolution for all 29 CRCOG municipalities. Realizing the cost savings by joining the CRCOG flight, seven other municipalities joined the program. The program was set up to allow each municipality to obtain additional data such as permanent monumentation, infrared digital orthophotography planimetric and/or topographic mapping up to 1”=40’ scale data with 2’ contours.

Giving the versatility of using digital sensors, WSP utilized digital sensors to acquire the four band imagery. These sensors will allow our photogrammetrists to extract color and/or infrared imagery. The digital imagery was flown at an altitude to capture a resolution at 1.8” ground sample distance.

Prior to the flight, existing control was targeted. Additional locations required some GPS survey data to supplement the airborne GPS data. Digital triangulation was performed to validate the field and airborne GPS data.

WSP obtained LiDAR that would be used as the DEM during the Orthorectification process. This LiDAR was used for the communities that did not have any existing DEM data, mainly the rural areas of the project limits. Additional breaklines were established in areas to help better define the DEM surface.

The digital imagery and the LiDAR data was acquired in leaf-off conditions. The digital imagery was collected at a time of day when there was a high sun angle (to minimize shadows). The imagery was integrated with the LiDAR and breakline data for the orthorectification process. True color digital orthos were created at 0.25’ (3”) ground sample distance. This data was delivered in GeoTIFF and MrSID (30:1 compression) formats.