Photo Credit: Mike Wier, CalTrout


​Klamath dam removal should proceed as planned in the early months of 2023. Removal will have resounding positive impacts throughout the Klamath Basin and will reconnect hundreds of miles of river long impassable for migrating salmon, steelhead, and lamprey. Once the J.C. Boyle, Copco 1, Copco 2 and Iron Gate dams are demolished and the extensive environmental rehabilitation projects are underway, Coho and Chinook salmon runs will have unfettered access to extensive stretches of the Klamath River and its tributaries that have been largely unreachable since dam installations began in the early 1900s. These are critically important steps towards ensuring the productivity of salmon runs throughout the basin and the ongoing ecological restoration of the Basin as a whole. But to take full advantage of the opportunity afforded by dam removal, there’s more vitally important work that will need to be done.

Just down-stream of the dams that are being removed are the Scott and Shasta Rivers join the Klamath River. These key tributaries are important and prolific spawning and rearing grounds for Chinook and Coho salmon. These rivers will continue to be impacted by irrigation demands after the removal of the dam. For Klamath salmon populations to survive and recover post dam removal, new agreements and/or regulations need to be developed to provide effective oversight of water usage in the Scott and Shasta River watersheds.

The hydrology of these rivers is largely impacted by the amount of ground and spring water being diverted or pumped from within their watersheds. Rainfall is an important component in replenishing river flow, but water use planning is essential in maintaining in-stream flow levels in ways consistent with the needs of migrating anadromous fish populations such as Coho and Chinook salmon. If removing the dams from the Klamath River is to have the regenerative outcome desired by proponents, there needs to be ways to ensure that other water resources throughout the Basin are not gobbled up before downstream interests, both human and fish, get their fair share.

This post is an introduction to a series of posts that will further describe the spring and groundwater dynamics in the Shasta and Scott River watersheds. Each watershed’s spring and groundwater is managed differently, and the realities created by these divergent management regimes are important in understanding how to propose new modes of water management and utilization. Next week’s post will dive further into ca various sources of irrigation and their outcomes for Coho salmon in the Scott River. The following week’s post will focus on realities for Chinook salmon in the Shasta River.