Tenmile Creek Gage Re-initiation

The purpose of this project is to reactivate a historic United States Geological Survey (USGS) surface water gage (#11475700) at Tenmile Creek near Laytonville, CA, and record high-quality stream gage data and water temperature in real-time and available for the public on the California Data Exchange Center (CDEC). This gage was active from October 01, 1957, to December 14, 1977 and recorded daily discharge (cubic feet per second) for a drainage area of 50.3 square miles in Mendocino County (Hydrologic Unit Code 18010106). Tenmile Creek supports all three ESA-listed Pacific salmon species including Chinook Salmon, Southern Oregon/Northern California Coho (SONCC) Salmon and steelhead trout, and the National Marine Fisheries Service’s intrinsic potential habitat maps indicate that Tenmile Creek had more historically suitable habitat than the upper South Fork Eel River, which currently has one of the last functioning SONCC Coho Salmon meta-populations (NMFS 2014). This project is crucial for a wide range of stakeholders—including resource managers, restoration practitioners, natural resource agencies, and cannabis cultivators—because it provides reliable, long-term hydrologic data essential for informed decision-making. For managers and restoration practitioners, continuous flow data supports efforts to assess watershed health, track timing and magnitude of instream flow relative to restoration (e.g. the recent Wildlife Conservation Board-funded Black Oak Ranch Water Conservation and Flow Enhancement Project), and plan projects that enhance stream function and resilience. Natural resource agencies rely on gage data to protect aquatic habitats and species, particularly during low-flow periods critical to fish survival. For permitted cannabis cultivators, access to accurate streamflow records helps ensure compliance with water diversion regulations, align operations with environmental flow needs, and demonstrates responsible water use. Overall, restoring this data stream bridges scientific knowledge gaps and supports sustainable land and water management across the region.