Mattole River Headwaters Groundwater, Streamflow and Habitat Enhancement

The Mattole River watershed, spanning the Humboldt-Mendocino county line, and adjacent to the King Range National Conservation Area, is home to a diverse array of forest, meadow, and riparian habitats that support such rare, threatened, or endangered species as northern spotted owl, goshawk, tailed frogs, pacific giant and southern torrent salamanders, as well as federally listed coho, Chinook and steelhead salmonids. The Mattole River headwaters provides the key spawning and over-summer rearing habitat for endangered salmonids in the river system.

Past logging practices and misguided efforts involving the widespread removal of wood from stream channels from the 1950s-1980s, due to concerns about the effects of instream wood on fish passage, have resulted in a substantial instream wood deficit in the Mattole. Additionally, since 1999, drought and a pattern of longer dry seasons has resulted in low to no flow in several important fish bearing tributaries and main stem reaches. Land use impacts combined with these longer dry seasons are resulting in extreme water scarcity impacting all wildlife. Water sustainability for the local community is also a critical issue, as there is no municipal water system in the Mattole headwaters and residents are on their own to provide for their water needs (sourced from pumping directly from the river and storage in water tanks, or from springs and wells).

Sanctuary Forest has worked toward the recovery of native Mattole salmonids since 1987, and has taken the lead in solving the streamflow problem conducting extensive research over the last 20 years with local and regional scientists, restoration groups, state agencies, and the local community. This project incorporates innovative methods to improve instream habitat and connection to side channels, increase groundwater storage and summer streamflows, restore floodplain connectivity and riparian habitats, and create greater resiliency to drought in the face of a changing climate.

Through these efforts, significant streamflow enhancement benefits vital for salmonid recovery efforts will be achieved, as well as ecological benefits for all wildlife. Furthermore, the restoration of ground and surface water will significantly reduce the need for storage in water tanks and will result in long term water sustainability for the local community.

* Project restores natural hydrologic conditions to facilitate improved capture and infiltration of surface water and groundwater recharge


Whitethorn, CA

Start Up Date:


Project Benefits:

Environmental Flow Restoration & Protection

Groundwater Conservation & Replenishment

Securing Water for Communities & Food Production

Wildlife & Habitat Protection

Project Type:

Restoration of Natural Hydrology *


Funding Needed