Table 4 Cost/benefit analysis of performing a lake census over the Southern High Plains, Texas, using a ground survey (automobile), contract aerial photographs, a light airplane, and ERTS-1 satellite data (MSS and CCT). 1scale used for mapping or scale of images or CCT data most workable 21abor based on man @ $1000/mth or $50/day CPU cost about $54/scene 3 frequency does not allow for inclement weather 4 use of one plane only Table 5 Results of measuring water areas and mud are as in the Double Lakes test site by the Stanford Research Institutes ESIAC (from 9 x 9 MSS positives, Band 7). playas. For example, on May 30, 1973, the Double Lakes test site contained 7 1/2 inches of water, by June 19 only 1.1 inch, and by June 26 the playa was dry. However, by July 27, the playa again contained 1.0 inch of water, yet the only imagery available of this sequence is the June 18 pass. It is, therefore, inferred that a shorter period for satellite imagery would be of greater value, particularly when working with playa-type lake budgets and meteorological events in semi-arid to arid areas. REFERENCES Reeves, C.C., Jr., 1973a, ERTS-1 Imagery for Water Resources Asso. Symp. on Remote Sensing, Burlington, 1973b ERTS-1 Cost/Benefit Analysis Using MSS and CCT imagery for Water Resource Inventory: Amer. Geophys. Union, Fall Meeting, San Francisco. Texas Water Development Board, 1968, The Texas Water Tison, L.J., 1970, Inventory of installations for artificial recharge of underground water levels: Inter. Asso. Scientific Hydrology Pub. 87, 762 p. |