Understanding legal protection

Water law in the U.S. is complex soup of federal, state, and administrative laws. This page is intended to provide you with a basic lay of the land from which you can explore further on your own. State law generally governs how water rights are allocated and assigned except when otherwise reserved for federal purposes (e.g., federal lands and rights associated with sovereign nations/tribes). Administrative law and regulatory systems come into play when seeking surface water or groundwater withdrawal permits (or discharge permits). Where do you start? Start with your state.

As a result of history and geography, states use one of three approaches for assigning water rights: The Riparian Doctrine, Regulated Riparianism, and the Prior Appropriation Doctrine (California’s approach is a bit of Riparian and Prior Appropriation):

  • The Riparian Doctrine is traditionally followed in states located East of the Mississippi River and was the approach most familiar to early European settlers: The owner of land that borders a water body, river or lake, has the right to a reasonable use of water. This right is shared by other riparian land owners, cannot be lost by non-use, and generally cannot be separated from the land. When there is a shortage, all landowners with rights share in the loss. A modified form of this doctrine, Regulated Riparianism, is now more common. Typically codified in state statutes that create an administrative permit system, this approach allows states to authorize water uses as part of a comprehensive process and to place restrictions on water withdrawals and water use based on amount, timing, environmental impact, and other factors, as well as to allow communities to access water supply.
  • The Prior Appropriation Doctrine is largely followed by states west of the Mississippi River and has historical roots in the need to divert water for mining activities as well as scarcity in some areas. The phrase “first in time, first in right” is often associated with this doctrine – The first one to put the water to beneficial use has a priority right to the water for that use. Junior rights are met after senior rights are fully satisfied. This right is transferrable and land ownership is not required to obtain a water right.

Although these three basic approaches can explain how surface water rights are allocated, the reality is often far more complex given the interplay between surface water and ground water, the impact of return flows, the challenge of monitoring withdrawals, the management of dams upstream, the effect of compact decisions, and assorted administrative and regulatory decisions and rulings. Creating a map of water rights and withdrawals for your river (and noting seniority if in states where the Prior Appropriation Doctrine applies) can be really useful when trying to determine how to protect your river’s flow regime.

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