A state has a duty to ensure that its water resources will be available for present and future generations. All water is broken down into two types: navigable and nonnavigable. For title purposes, a small boat, canoes, kayaks, rafts, or even a log can make it down the water, then its navigable. In short, you can't use a small boat in nonnavigable water.
NAVIGABLE & NON-NAVIGABLE WATERS
The state owns all navigable waters and streams, which are for the use of the public. As such, no one has an exclusive right to the enjoyment of navigable waters unless the legislature passes a law to the contrary.
In most jurisdictions, nonnavigable waters may be privately owned, and the rule, in the absence of any constitutional or statutory provision to the contrary, is that nonnavigable waters belong to the owner or owners of the land upon or over which they stand or flow.
A body of water that is navigable but not necessary for commerce may be privately owned, subject to a right of access in the public. (Check your state law.)
Each state establishes its own rules regarding the ownership of the natural streams and other bodies of water, both navigable and nonnavigable. However, every rule must conform with constitutional prohibitions against interference with vested rights or the taking of private property for public use without just compensation. In addition, the federal government trumps state authority when it comes to navigable waters because navigable waters can be used for interstate and international commerce.
Water rights are generally described as real property rights. In some states like California (no surprise), it is an extremely complex body of law. Water rights are based on a priority system that is used to determine who can continue taking water when there is not enough water to supply all needs. Those with high priority rights know that they are likely to receive water; those with low priority rights know that they may not receive water in certain years and must plan accordingly. In agriculture, water resources has a huge impact on farmers' economic decisions. For instance, farmers who know they're going to receive a lot of water, even during a drought, will plant higher revenue permanent crops like fruit trees or vineyards instead of seasonal crops.
Each state has different laws regarding how people can use the state’s water. All western states have enacted laws that require water users to get a permit from the state. In general, those laws provide the highest priority to the earliest water users.
Riparian Doctrine: A riparian water right is a right to use the natural flow of water on riparian land. Riparian land is land that touches a lake, river, stream, or creek. Land that is in the public domain does not have riparian rights. Most western states either never recognized riparian rights or no longer do so, except for California and Oklahoma, both of which continue to recognize riparian rights.
Appropriative water right: Someone who takes water for use on non-riparian land or who uses water that would not be there under natural conditions on riparian land appropriates water.
Prior Appropriation Doctrine: Generally follows the principle of “first in time is first in right”. That is, a priority is established for water rights that are based on the date that the water was first put to beneficial use. Junior priority rights may be fully or partially curtailed in times of short water supply to ensure that senior appropriators (water right holders) receive their full appropriation (legal share).
Surface and ground water in Idaho and many of the western states are managed under the Prior Appropriation Doctrine (see above).
In Montana, all water is owned and controlled by the State. You can either do a title search or search Montana's water rights database to look up the status of the water rights on your property.