Jan and Harry Vaughn continue to do an incredible job of organizing and coordinating our Salmonids in the Classroom project. This spring they had 75 egg hatching/fish-rearing tanks in classrooms in Humboldt County. The late April rains delayed the student fish planting field trips to the point where there is overlap with the tagging and release of our project's 60,000 Chinook salmon smolts--a hectic time!
My major activity during the long rains was turbidity monitoring of various tributaries of Redwood Creek (the Redwood Creek near Redway). This information will be used as baseline data for a Miller Creek watershed road modification project to reduce road related sedimentation. The project will be completed this summer and post-project monitoring will be conducted next winter.
Chronic erosion from our active watershed road systems has a serious negative effect on fish. There's some good research information coming out on the effects of stream sediment on the growth and survival of salmon and steelhead. At a turbidity of about 20 NTU (when the water starts to look a little muddy) feeding of juvenile fish drops off by about half. This obviously affects their growth rate and size when migrating to the ocean. Larger juvenile fish have a considerable higher rate of return as adults.
It doesn't take much of a storm to muddy many local streams. Consider this: a three-quarter inch storm on March 22 raised the turbidity of Miller Creek from 4 to 41 NTU, China Creek from 4 to 90 NTU, Seely Creek from 11 to 237 NTU, and Redwood Creek at Ruby Valley from 6 to 182 NTU - all very muddy streams draining watersheds with many actively used gravel roads. On the other hand, Upper Redwood Creek went from 2 to 6 NTU during the same storm-almost clear. This watershed is on corporate timberland, with an extensive road system that is not driven on in the winter. Once the finer material on the roads has washed off, leaving a coarser protective layer on the surface, the sediment production from these undisturbed roads drops off to low levels during small to moderate storms. It's sobering to stand at the confluence of Upper Redwood Creek and China Creek and watch clear water merge with muddy water.
In the Miller Creek watershed, out of the 18.9 miles of active roads and driveways, 4.2 miles of road has direct, stream-connected drainage. By altering the drainage where we can, the roads with stream-connected drainage can be reduced to less than.4 miles. The really bad apples are the long inboard ditches that puke mud directly into tributaries of Miller Creek. Fortunately most of these stretches of road can be outsloped
onto gently sloping areas where the muddy water will be dispersed and not reach the stream.
Two things really excite me about this project. The first is doing it on an entire watershed, and the second is measuring the stream turbidity before and after the drainage alterations. I'm convinced that we will see significant improvements
in water clarity. Tune in next spring for the answer.
The California Department of Fish and Game and the Cereus Fund are funding this year's work of the ERSRP.
More Updates
Main Page
