Verde River Diamond-S
The Verde River is Arizona’s only designated Wild and Scenic River. It delivers 40% of the surface water for the Phoenix metro area and is a critical Colorado River tributary providing diverse ecological benefits for myriad native desert fish and wildlife species. However, like many rivers in the West, the Verde River suffers from the existence of so many dams and diversions that, in places, the river’s flow is inadequate to fully support native fish, wildlife and recreation.
For example, between the towns of Clarkdale and Camp Verde, AZ, seven major irrigation canals divert water from the river. These diversions leave the river dry in places and can chronically dewater long sections of the river during critical times of the year. As a solution to restore flow to the river, The Nature Conservancy’s Verde River Program has begun working collaboratively with local irrigators and communities to identify irrigation infrastructure improvement opportunities and to explore water efficiency solutions that can restore flow to the Verde River while meeting the needs of local irrigators. The long-term goal is to provide water for local agriculture while restoring connectivity and stream flow throughout the Verde River to support fish, wildlife and recreation.
The Verde River Water Restoration Certificate® (WRC) flow restoration project is located near Camp Verde, AZ. Under historical conditions, area irrigators diverted the majority of the river’s flow into their irrigation canals during the dry summer months. Typically, the canal system would divert 30 or more cubic feet per second of flow from the river, and water that was not used by irrigators would flow through a five mile long ditch and be returned to the river at the end of the ditch. The consequence of this very large diversion is that the mainstem Verde River is seasonally dewatered over a 4.5+ mile section where the ditch bypasses water around the natural river channel.
Recent calculations have shown that the agricultural users that rely on the irrigation ditch do not use a significant portion of the water that is actually diverted through the ditch system. This is in large part because the antiquated infrastructure in the ditch cannot be adjusted to effectively control how much water is diverted and delivered to each property. Thus, without infrastructure improvements in the ditch system, the irrigators are forced to divert most of the river’s flow through their canal system even though much of this diverted water is not used for irrigation.
The Nature Conservancy’s Verde River team coordinated with local irrigators to propose a solution: if funds could be raised to install new infrastructure in the ditch system—such as modern, automated control structures that allow the irrigators to precisely control how much water they divert—irrigators agreed that they could meet their farming needs while leaving significant amounts of “restored” water in the Verde River. BEF partnered with The Nature Conservancy to provide funding to help advance the first two phases of this project. And while restored flows will be closely monitored and tracked, we anticipate that the project will restore up to 4 cubic feet per second of new flow to the Verde River during the first full phase of this project.
This project restores flow to the dewatered river reach that is immediately adjacent to the Wild and Scenic River section of the Verde River. As a result, the project extends viable habitat for several at risk and endangered fish species including the Razorback Sucker, Pike Minnow, Loach Minnow and Round Tail Chub. Importantly, the project has strong local support from irrigators (who will continue to receive their full allotment of water) and from local communities that desire to establish river recreation and tourism on the Verde River. BEF’s Nature Conservancy partners estimate that the project will restore approximately 64% more flow to the river during times of drought and extreme low flows.
* Improving water use or management in agriculture
** This resource has been reviewed and found to meet the BEF Flow Program Certification Criteria for Evaluating Proposals to Secure Environmental Flows by the National Fish and Wildlife Foundation.