Multiobjective Management of Potomac River Consumptive Use

Abstract

Multiobjective systems analysis is used to size reservoir storage and identify noninferior system operating rules that mitigate the impacts of consumptive appropriations. The marginal impacts of consumptive use are offset by adding reservoir storage to the system, balancing technical efficiency, economic efficiency, and equity. The “price” to receive a consumptive appropriation permit (augmentation storage) is effectively equal to the marginal cost of the new withdrawal. In this context, prices and costs are measured not in dollars, but in units of storage, days at minimum instream flow, and the 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 reliability of meeting unrestricted demands. Parametric operating rules to size augmentation storage are developed as a multiobjective extension of firm yield analysis, applied to forecast-based operation of a multireservoir system. Examples drawn from Maryland's Potomac River consumptive use regulation illustrate how operational definitions of equity and reliability offer a normative framework to manage risk-based appropriation within a permitted riparian regulatory system.