Press release from the Eel River Recovery Project:
The Eel River Recovery Project (ERRP) is conducting fall flow reconnaissance while collecting automated water temperature gauges and recently surveyed three important northern Mendocino County tributaries: Outlet Creek, Tenmile Creek and the upper South Fork Eel. The lack of rainfall in February 2020 and low rainfall in the southern part of the Eel River watershed through the rest of last winter are resulting in extensive dry stream reaches and record low flows downstream at South Fork Eel River gauges.
Outlet Creek is a major tributary of the upper Eel River that has headwaters above the city of Willits. Upper Baechtel Creek is one of these headwaters and has maintained surface flow in most years since 2012, or at least cold water pools with steelhead trout juveniles. In 2020, this reach is dry and fish-less. Broaddus Creek was also dry and without fish of any kind, as was Mill Creek below Willits Creek. Willits Creek barely maintained surface flow below Brooktrails and riffles were too shallow to support steelhead, but pools there provided some of the only cold-water habitat in the Outlet Creek watershed in 2020.
Outlet Creek below Highway 101 at the bottom of Little Lake Valley lacked surface flow, however reaches downstream of there and above Long Valley Creek maintained surface flow and California roach were present and abundant. Lower Long Valley Creek was warm but connected with roach surviving, while the upper-most reach of the creek at Highway 101 was dry. In sum, Outlet Creek is exhibiting severe ecological stress and is failing to support cold-water fish species, with only limited reaches supporting any fish life at all.
A survey of Tenmile Creek near Laytonville had more mixed results. Main Tenmile Creek ran dry above Highway 101, near Harwood Park and downstream near the Black Oak Ranch. However, it had surface flow in a middle reach supported by springs and retained steelhead trout. Lower reaches of Cahto, Streeter and Big Rock creeks are underground. None the less, headwater reaches of these creeks maintained cold water and steelhead trout as did Mill Creek and Peterson Creek. The extent of steelhead distribution and standing crop in Tenmile Creek is far less than in 2019.
Tenmile Creek feeds the upper South Fork Eel River, which is experiencing the lowest flow levels ever at U.S. Geologic Survey flow gauges at Leggett and Miranda. On October 20, the Leggett gauge reported 11.6 cubic feet per second (cfs), only barely higher than the record low in 2002 of 11 cfs, while the median flow for the previous 50 years is 29 cfs. The USGS gauge at Miranda was 13.5 cfs, which was at an all-time record low for the date, and less than one third of the median flow of 56 cfs derived from 81 years of data. The lower Eel River at Scotia measured 65 cfs on October 20. While not a record low, flow this is far less than the 108-year median flow of 147 cfs and the 200 cfs adult salmon need for migration.
The last viable population of coho salmon in northwestern California is in the upper South Fork Eel in Mendocino County. While tributaries like Jack of Hearts and Redwood Creek ran low, they remained cold but had no coho salmon juveniles. Dutch Charlie Creek in the same vicinity had similar flow levels, but also abundant coho salmon. It appears that excess sediment is impairing habitat and may be more limiting than flow in this area of the upper South Fork watershed.
For more information see www.eelriverrecovery.org or the ERRP Facebook page. Call 707 223-7200, if you have questions or you want to volunteer.