South Fork Stanislaus: Hwy 108 out of Sonora is the main route taking you to both the South and Middle Fork of the Stanislaus River. The South Fork can be reached from Lyons Reservoir off Lyons Reservoir Road at Sierra Village. A trail extends along the north side of the river upstream from the Reservoir. Further along Hwy 108, you can reach another section of the SF Stanislaus at Fraser Flat Campground from Spring Gap Road south of the village of Cold Springs. The last access to the SF Stan is where Hwy 108 crosses the SF just below Pinecrest Lake.
Middle Fork Stanislaus: The Middle Fork can be reached via Spring Gap Road continuing onto Sand Bar Flat or upriver to Spring Gap, 3 miles below Beardsley Reservoir. Another route is to take Road 52 from Strawberry to the Beardsley Afterbay. Continuing past the Afterbay, a trail will take you down to Spring Gap Footbridge.
Hwy 108 continues past Strawberry to Donnell Reservoir. From that point , the Highway 108 follows the river up to it's headwaters at Kennedy Meadows.
Notes:
The Middle Fork of the Stanislaus River has been building a reputation over the years as having some of the best fishable waters westside of the Sierras. Most of this reputation has come form the nutrient-laden waters below Beardslet Reservoir resulting in excellent aquatic insect populations of stoneflies, caddis, mayflies, and midges. A 17 mile section from Beardsley Afterbay to the confluence of the North Fork Stanislaus is designated by the State of California as a Wild Trout Fishery. At Beardsley Afterbay, you can fish year-round with a two-trout limit of 14 inches and must use barbless flies or lures. It can be fished by float tubes during low flows or along the banks. Beyond the Afterbay to Spring Gap Bridge, a distance of 3 miles, it is still barbless flies or lures but the season is the last Saturday of April to Nov. 15th. These areas consist of both Rainbows and Browns up to 17", with some trophy-sizes available. The remainder of the Middle Fork Stanislaus is open to all types of fishing, bait or fly. A foot trail is available for access along the river from Spring Gap Bridge to Sand Bar Flat, a distance of 4 miles. Downstream of Sand Bar Flat, the trail fades quickly and you enter the rugged canyon reach, only lightly fished because of its difficult access, as the river comes down to its confluence with the North Fork, 10 miles further.The river is characterized by large boulders and deep pools with scattered pocket water sections. Best fishing starts in Mid-June after the Reservoir slows its releases to less than 200 cfs.The South Fork of the Stanislaus above Lyons Reservoir contain some good sized browns. It has good fishable waters up to Pinecrest Lake with trail access along the river. Most of the access points are planted but a sizeable population of wild trout exists not far from each access point. The DFG puts in about 8,000 rainbows annually from Fraser Flat to Strawberry but the stream is so heavily fished that many of these stockers are caught and kept within 4-5 days. Fortunately, there are many wild trout which aren't caught easily by bait and help keep the stream a viable fishery. The Spring run-off makes the stream difficult to fish until late June and, since the South Fork is smaller than the Middle Fork, it is considered to be a better "early-season" trout stream to the end of July
