Emerging Trends in Streamflow Restoration in Montana

The Clark Fork Coalition is currently laying the foundation for large scale flow restoration in the upper Clark Fork river basin of Montana.  The upper Clark Fork river basin is a 3,710 square-mile watershed with a 150-year history of heavy use for mining, forestry and agriculture.  The ecological connectivity of tributaries and the mainstem river has been severely compromised by a combination of irrigation-related dewatering, elevated water temperatures, impassable irrigation infrastructure and inadequate road drainage structures.  This problem limits the ability of fish to move seasonally in and out of tributaries and up and down the river mainstem. Ability to migrate is fundamental to the survival of the sport and native fishes of the Clark Fork.

Flow restoration is critical technique to address a series of inter-related problems, including dewatering of tributaries or the mainstem, hydrologic disconnection of tributaries from the river, elevated water temperatures, and chemical water quality issues (dilution opportunities).  Flow restoration techniques commonly used in Montana include: 1) the acquisition of water rights for dedication as in-stream flow; 2) water leasing; 3) salvage water leasing/efficiency improvements. 

The acquisition of water rights for instream flow restoration offers long-term assurances for permanent flow restoration.  In Montana, there is no active market for water rights, and it is difficult to place a value on a given right. The Clark Fork Coalition believes water rights acquisition should be used only in certain instances where sufficient water is available or land uses have changed, to avoid pressure to “dry up” farmland, which is not good for the agricultural community.

Water leasing is usually a short-term option for flow restoration. Water leases in Montana are time-limited, and the current landowner, or future landowner could terminate the lease and negate the benefits of a given flow restoration opportunity.

Salvage water leasing is possible when an irrigation efficiency improvement allows a water user to decrease the diversion of water from the stream while still satisfying crop demands. Efficiency improvements, such as a switch from flood irrigation to pivot sprinklers, or lining a leaky canal, are combined with a formal change of part of the right to in-stream flow. 

Because flow restoration can only be accomplished through the voluntary participation of willing private landowners, meaningful and effective flow restoration in the Clark Fork basin will only occur if water transactions can be structured to provide a net benefit to working farms and ranches.