Hydrographic Surveying
  Howard Hanson Dam | Brantley Reservoir | Ute Reservoir

Static GPS survey techniques were used to establish control for this project, which was brought to the site from the Continuously Operating Reference Station (CORS) at the Tucumcari Municipal Airport, approximately 25 miles away. A static control network was established encompassing the project area and a total of 42 square miles were mapped with 10 square miles required to complete the bathymetric section of the survey. Aerial photography was performed to obtain contour information for the terrestrial portion of the survey. Bathymetric surveys were conducted using a fathometer integrated with RTK GPS. Several challenges were overcome to successfully complete this project, including the size and limited access of the project area. Steep cliffs and adverse lake conditions were two other factors that required careful planning. Tetra Tech integrated data from the aerial and bathymetric surveys to perform a sediment analysis and to develop area capacity tables for the client.