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I I I I I I I I I I I I I I I I I I I AYRES ASSOCfi~TlES Mapping services Aerial Photography Acquisition Aerial photography will be obtained in the spring of 2003. Ayres Associates will obtain black and white aerial photography of the project area from a flight altitude of 1,980 feet above mean terrain which will result in a negative scale of 1"=330'. Control Survey and Targeting Control survey and targeting sufficient to support digital terrain model (DTM) development, topographic, and planimetric mapping will be conducted. Ayres Associates will establish coordinates for 55 ground control points utilizing GPS methodology. Existing points will be used whenever possible, reducing our project fees for this phase of the mapping effort. Planimetric Mapping We will collect planimetric features from the aerial photography using photogrammetric methods. Our fees include the collection of 3D road centerlines and hydrology. We will tailor the planimetric feature collection to reflect specialized features that may be of value to the City of Boulder. Digital Terrain Model (DTM) Development and Topographic Mapping Ayres Associates will develop a Digital Terrain Model of suitable density to either produce one-foot contour interval topographic mapping. The DTM will be created using photogrammetric techniques using the 1"=330' photography. One-foot contour mapping will be produced from the DTM. Digital Orlhophotography Film negatives of the 1"=330' black and white aerial photography will be scanned at 15 microns on a photogrammetric scanner. The DTM will be used to rectify the scanned aerial photography. Digital orthophotography with a 6" pixel resolution will be produced and delivered as tiled GEOTIF and MrSID (compressed) images. Mapping Deliverables The following items represent a typical list of deliverable products for a project of this nature. These deliverables will be tailored to meet the needs of the City of Boulder. The files can be in any CAD or GIS format the City requires. The following list was drafted with the assumption that the City will require Arclnfo compatible formats. . One copy of the flight plan, including control layout in both hard copy and digital form. . One set of contact prints of the aerial photography. . One copy of the ground control report in hardcopy and digital form. . One copy of the analytical aerotriangulation report in digital and hardcopy form. . One copy of the digital terrain model in Arclnfo format. . One copy of the contours in Arclnfo format. . One copy of the planimetric features in Arclnfo file format. 29