MUS is economically feasible depends on the circumstances of particular locations—not only the technical requirements of a particular MUS project, but the alternatives that are available for water supply and storage and the financial resources that can be marshaled.
Municipal and industrial suppliers in water-short regions, for example, are able to pay almost any price to meet water demands that are increasing in the face of growing populations or to respond to the mining of groundwater aquifers, increasing regulatory constraints on surface water storage, and regional water competition. Furthermore, communities in almost any location have alternative means of addressing these water demands, such as conservation measures, pricing practices, or transfers of water from other uses (e.g., retiring of agricultural water rights is occurring across the western United States).
Institutional arrangements also determine whether MUS comes within the set of feasible policy options. Institutional constraints affect whether recovered water can be stored underground, that is, whether a legal regime exists that would prohibit or permit this activity. The coordinated actions necessary for implementation of an MUS program are unlikely to occur if rules and organizational arrangements (1) impede or prohibit coordination of actions necessary to divert, impound, treat, recharge, store, protect, and extract water; (2) do not protect those who invest in facilities or who store water now for later recovery; or (3) do not provide or recognize workable and fair methods for distributing the costs of an MUS program among those who benefit from it (Blomquist et al., 2004).
Those who would invest in MUS projects need to capture and internalize benefits from their investments. Those who incur costs by participating in an MUS program (e.g., accepting recovered water supplies in lieu of other supply sources to which they also have access) must be able to capture some of the benefits they have provided for others. The assurance of the protection of public health and the environment is also critical in MUS development and operation.
Other major institutional considerations in MUS involve the nature of the organizations (public or private) and the allocation of their authority and responsibility to capture, convey, manage, store, or sell water; to monitor water resource conditions and respond to perceived problems; to communicate with the public and other policy makers; and to protect public interests. Like any approach to water management, MUS emerges through the interaction of multiple organizations with diverse interests and responsibilities. The practices of those organizations and the relationships between them shape the implementation and performance of MUS. This chapter provides an overview of the regulatory involvement in the development and oversight of these technologies; a discussion of other issues facing institutions in their approach to MUS; and an evaluation of the economic aspects of MUS.