This report documents the results of a lost-effectiveness study of the streamflow-gaging program in Wyoming. One phase of evaluating the cost effectiveness considers the use of alternative methods to simulate streamflow records. Regression analysis or hydrologic flow-routing techniques were considered for 24 combinations of stations from a 139-station network operated in 1984 to investigate suitability of techniques for simulating streamflow records. Only one station was determined to have sufficient accuracy in the regression analysis to consider discontinuance of the gage. The evaluation of the gaging-station network, which included the use of associated uncertainty in streamflow records, is limited to the nonwinter operation of the 47 stations operated by the Riverton Field Office of the U.S. Geological Survey. The current (1987) travel routes and measurement frequencies require a budget of $264,000 and result in an average standard error in streamflow records of 13.2 percent. Changes in routes and station visits, using the same budget, could optimally reduce the standard error by 1.6 percent. Budgets evaluated ranged from $235,000 to $400,000. A $235,000 budget would increase the optimal standard error for the current budget from 11.6 to 15.5 percent, and a $400,000 budget could decrease the optimal error to 6.6 percent. For all budgets considered, lost record accounts for about 40 percent of the average standard error.