Prepared by the Water Regulatory Standards Committee of the Standards Development Council of the Environmental and Water Resources Institute (EWRI) of the American Society of Civil Engineers

Regulated Riparian Model Water Code, ASCE/EWRI 40-18, provides a complete, comprehensive, and well-integrated statutory scheme for creating or refining a regulated riparian system of water law. This system uses a requirement of administrative permits for larger water uses, issued based on the well-established principles of riparian rights, to balance and coordinate those uses in times where demand is approaching or outstripping the available water. This standard addresses  allocation of water for particular uses and  coordination of water allocation processes with water quality regulatory processes.

This standard covers declaration of policy; basic definition for the code; waters subject to allocation and those waters exempt from allocation; general administration authority, planning responsibilities, and coordination with other branches of government; enforcement and dispute resolution; establishing a water right, including the requirements of a permit and permit procedures; scope of the water right, including modifications and restriction during shortages; multijurisdictional transfers; and water conservation and supply augmentation.

Standard ASCE/EWRI 40-18 provides engineers, attorneys, and government officials guidance on the allocation of water rights among competing interests and the resolution of quantitative conflicts over water.