This dataset represents an AOI, true-color orthophoto (3-band) mosaic of the Trinity River study area located in Trinity County, California. The data is projected in California State Plane Zone 1, the horizontal datum is NAD83(Epoch 1992-1991.35 Adjustment) and units are in US survey feet. The acquisition flight parameters were designed to yield a native pixel resolution of 0.5 ft. Quantum Spatial subcontracted Geoterra Inc. to collect the Orthoimagery data on 16/08/03 for GMA Hydrology Inc. Data were initially generated in MrSID format with 20:1 compression (available as needed), then converted by TRRP to JPeg2000 format with an effective ratio about 50:1 for efficient storage and faster display while retaining quality and detail.