The SDRGC Imagery Subcommittee presents The San Diego Sub-Regional Imagery Acquisition Project Status and Next Steps June 24, 2008

Imagery Subcommittee Introductions  Wendy Flynn, City of Encinitas  Mettja Kuna, City of San Marcos  Karl Von Schlieder, City of Carlsbad  Sue Carnevale, SANDAG  Grace Chung, SANDAG

Imagery Subcommittee Assistance  Cheryl Mason, SANDAG Service Bureau  Drew Decker, USGS  Paul Hardwick, SDSURF and SDRGC  Barbara Kent, CALTRANS and SDRGC  Pat Landrum, CALTRANS

Brief History of Past Sub-Regional Imagery Projects  2001 effort led by San Diego County Water Authority  Methods: Traditional photogrammetry; film-based photography.  Deliverables: 6” orthos, 2 ft. contours.  Administration: Separate contracts.  2004 effort led by Chula Vista  Methods: Traditional photogrammetry; film-based photography.  Deliverables: 6” orthos, 2 ft. contours.  Administration: One joint contract.  2005 effort led by the City of San Diego  Methods: LiDAR; film-based photography.  Deliverables: 3” orthos, 2 ft. contours, LiDAR generated terrain model.  Administration: Separate contracts.

Project Background and Current Status  Project Specifications and Requirements  Current Caveats and Assumptions  Imagery Subcommittee Efforts To-Date

Project Specifications  4" digital true-color orthophotos,  Delivered in 2000x3000 ft GeoTIFF tiles covering an agency's selected area of interest,  Captured with a digital matrix array camera,  With positional accuracy to be sufficient for producing 1“ = 100 ft scale planimetric mapping (ASPRS Class 1 Accuracy Standards for Large Scale Maps),  Delivered in CA Stateplane coordinates NAD83, 1993 HARN adjustment, Vertical datum NAVD88,  and color-balanced across the entire project area.  These are not true orthos and may contain an acceptable amount of building lean.

4” resolution true-color digital imagery example

Project Requirements  A high resolution terrain model covering the entire project area is required for this project.  Agencies who already have an existing high resolution terrain model (e.g. LiDAR) can submit their DTM to the select vendor for use in the project.  Agencies who do not have an existing high resolution terrain model will need to acquire one for their AOI as part of this project in order to rectify the imagery to the required positional accuracy specs.

Current Terrain Date – Merrick 2005 LIDAR Coverage

Current Caveats and Assumptions  Vendors can merge high resolution DTMs in different formats to arrive at a uniform surface to produce orthorectified imagery within the required positional accuracy specs.  Vendors can produce “on-the-fly” autocorrelated terrain models in areas where no terrain models exist for image orthorectification, but the process may not meet the required positional accuracy specs or be of sufficient quality to generate 2-foot contours.  Agencies who need terrain data may opt to use the autocorrelated terrain method at a lower cost, or have the selected vendor create a more accurate terrain model for better orthorectification at a higher cost. The latter option would include the terrain data as a deliverable.  Does SD County’s existing control monumentation cover the project area? Is it accurate enough? Will vendor set up panels for ground control? Are these required for digital imagery acquisition?

Imagery Subcommittee Efforts To-Date  Several meetings conducted.  Agencies contacted to select tiles.  Tile selections map created. Some agencies still need to select their tiles.  First draft of RFP completed.  Matrix developed to understand partner agency needs and possible constraints. Some agencies still need to fill out the matrix.  SANDAG approached to act as Administrative lead.

Partner Agency Feedback To-Date  These Agencies Are IN (e.g. No Constraints at this time):  Airport Authority, Carlsbad, Coronado, Encinitas, Imperial Beach, Oceanside, Poway  These Agencies Have Constraints (DTM, Cost, and/or Admin):  Borrego Water District, Chula Vista, County Water Authority, Escondido, San Marcos, SDG&E, Sweetwater, USFWS, Vallecitos Water District  These Agencies Have Not Yet Completed the Matrix:  Centre City Development, City of San Diego, Del Mar, National City, Navy, Port District, Santee, Solana Beach, Vista, Wild Animal Park  These Agencies Have Decided Not to Participate:  CALTRANS, County of San Diego, El Cajon, La Mesa, Lemon Grove, LWWD, NCTD, OMWD, SANDAG, Valley Center MWD

Thanks for your time and attention. SDRGC Imagery Subcommittee