Multiobjective management of Potomac River consumptive use

Multiobjective systems analysis is used to size reservoir storage and ident ify noninferior system operating rules that mitigate the impacts of consump tive appropriations. The marginal impacts of consumptive use are offset by adding reservoir storage to the system, balancing technical efficiency, eco nomic efficiency, and equity. The "price" to receive a consumptive appropri ation permit (augmentation storage) is effectively equal to the marginal co st of the new withdrawal. In this context, prices and costs are measured no t in dollars, but in units of storage, days at minimum instream flow, and t he other direct operating impacts of consumptive use. In return for "paying " the efficient marginal price to join the system, new appropriators become equal participants in regionally coordinated operation, with equal reliabi lity of meeting unrestricted demands. Parametric operating rules to size au gmentation storage are developed as a multiobjective extension of firm yiel d analysis, applied to forecast-based operation of a multireservoir system. Examples drawn from Maryland's Potomac River consumptive use regulation il lustrate how operational definitions of equity and reliability offer a norm ative framework to manage risk-based appropriation within a permitted ripar ian regulatory system.