In this Report, another screening method in the design of water resource systems -- termed the Effective Capacity Method, or Method II -- is suggested. As in Method I, the Equivalent Reservoir Method (May 1973), this again uses the equivalent capacity concept, but here the equivalent capacities downstream of the entire system, termed effective capacities, are calculated for each potential reservoir individually. The cost-capacity functions for each site are modified to cost-effective capacity functions and the required system storage is allocated on the basis of these modified cost functions