This doctrine has its roots in the Code Napoleon (1804) and English Common Law and has been applied primarily in states east of the Mississippi River. The basic provisions in the early 1800s were that:
- so-called "Riparian water rights" extend to the center of a non-navigable water course;
- navigable water courses belong in the public domain and cannot be obstructed (although it appears that access from privately owned stream banks could be denied);
- mills or milldams could be developed by landowners with stream bank holdings and could be transferred upon sale of property;
- beyond use for millraces, excess water could not be removed and water returned must be equivalent to that removed in quantity and quality; and
- riparian landowners must be compensated for illegal capture of water by others. This last stipulation was interpreted by the U.S. Supreme Court (in 1827) in a way that gave riparian landowners (those with properties bordering a stream) the right to make "reasonable" use of water in a stream. However, they cannot claim ownership of the water, nor can they divert or dam a stream to the detriment of other riparian landowners.
All states (31 states) east of the Mississippi River have water allocation laws based on the Riparian Doctrine. Any waterway that can be used for navigation in its normal condition is considered navigable. If it is only used for intrastate commerce or transport, it is under control of that state. If used for interstate or foreign commerce or transport, it is under the control of the Federal government. There is no "water ownership" under the present Riparian Doctrine and principles of Reasonable Use and Correlative Rights are applied. Riparian landowners can use any quantity of water as long as it does not interfere with the rights of other landowners. They must also, therefore, share the total flow of stream water with other riparian landowners; for example, during a drought, restrictions on water extraction can be enacted to allow all owners (users) a reasonable share of the reduced flow in proportion to their ownership of stream bank property. During floods, riparian landowners can take exceptional action to protect their property, regardless of consequences for other landowners. In addition, the Riparian Doctrine is being altered in some states to allow permits to allocate water based on rates of use and other factors that can be changed by the state at any time. Courts or state water agency officials settle disputes over alleged injurious water use. The Riparian Doctrine works because water resources east of the Mississippi River are not, in general, limiting and irrigation for agriculture is not necessary.