California Fly Fishing 3 min read

DIY Guide to Fly Fishing the San Joaquin River (South Fork) in California

Ken Sperry

Posted by Ken Sperry

May 6, 2020

San Joaquin River (South Fork) in California

In the Mono language, the San Joaquin River is called typici h huu’, which means “important, great river.” As the longest river in Central California, the San Joaquin certainly lives up to its Mono name. The South Fork of the San Joaquin is the largest branch of the river and is a system of tailwaters. The waters hold an excellent trout and aquatic insect population. This fork is also a popular destination for hikers and boaters.

The San Joaquin River’s other forks offer great angling opportunities as well. Master the South Fork and you will be well on your way to conquering the entire River. 

About South Fork San Joaquin

Fly Fishing in the San Joaquin River

The South Fork is about 48 miles long and drains about 60 miles northeast of Fresno. The Fork begins at Martha Lake near Mount Goddard. It flows northwest through Goddard Canyon and receives its smaller tributary, Evolution Creek.

From there, the Fork enters the Sierra National Forest before flowing west into Florence Lake. Below the Florence Lake Dam, the Fork flows north before turning west again. The Fork then receives its largest tributary, Mono Creek, and enters Madera County. Upon entering Madera County, the Fork joins the San Joaquin River near the Mammoth Pool Reservoir. Other notable tributaries of the South Fork include Rube Creek and Bear Creek.

The South Fork offers varying levels of difficulty for boaters. Above Florence Lake you can find Class VI to V+ whitewater, while other sections are characterized by gentle, meandering flows. Be sure to check the flow conditions before making your visit.

At the South Fork, you’ll find wild rainbow, brown, and brook trout.

San Joaquin River (South Fork) Map and Fishing Access Sites

map of fishing access spots on the South Fork San Joaquin River in California

Get Directions to the Fishing Access Points shown above with the DIY Fly Fishing Map

Best Places to Fish the San Joaquin River (South Fork)

The best places to fish the South Fork are below Edison and Florence Lakes. The eight mile tailwater section below Mammoth Pole, which is in a canyon, holds large trout. However, access is tricky in this area, so you might have better luck using the hiking trail along the River. From there, you’ll be able to access the water above Florence Lake.  

Since access to the Fork requires hiking, you will want to make sure you are in good shape before tackling this River. You should also travel with a companion for safety reasons, particularly if you are hiking to the canyon.

Stream Flow and Current Conditions

Be sure to check the stream conditions before heading out to fish the San Joaquin River (South Fork). The USGS stream gauge near Mammoth Lakes, CA provides a good indication of current conditions.

The graph below shows the stream flow (discharge) for the past 7-days. If flows are considerably above or below historical norms (yellow triangles on the chart) then fishing conditions ma not be ideal.


  • Temperature: 56.3 ° F
  • Streamflow: 127 ft³/s
  • Gage height: 3.95 ft
Temperature GraphStreamflow GraphGage height Graph

Best Time to Fish the San Joaquin River (South Fork)

The season for the South Fork of the San Joaquin River is from the last Saturday of April to November 15. Summer is the best season to visit this Fork, as very little fishing can be done in the spring. Fishing can also be productive on this Fork in early fall.

The most important hatch is the Blue-Winged Olive, and you’ll also see October Caddis, Cream Midges, and Terrestrials. A variety of baitfish are also present in the River, including sculpin, which are always on the menu.

Fly Box – What You’ll Need

Here is list of general fly pattern recommendations for the San Joaquin River (South Fork):

  • Midge (#16-26)
  • Western March Brown (#12-14)
  • Blue Winged Olive (#18-22)
  • Western Green Drake (#10-12)
  • Spotted Sedge (#14-18)
  • Slate Cream Dun (#14-18)
  • Trico (#20-24)
  • Tiny Blue Winged Olive (#20-24)

Gear Recommendations

A 9-foot 5-wt fly rod with floating line is perfect for fishing dry flies and small nymphs on the San Joaquin River (South Fork). A tapered 9-foot leader, with tippet size 3X to 5X to match the flies you are throwing, is pretty standard.

The San Joaquin River (South Fork) Fishing Report

Area fly shops, guides and websites that can provide an the San Joaquin River (South Fork) fly fishing report are listed below:

Fishing Regulations

The state of California requires that all people who are 16 years of age and older have a valid fishing license. There are resident and non-resident sport fishing licenses available. You can purchase a one-year, 10-day, two-day, or one-day license. Some areas also require a permit. You can purchase the license and learn about the most current regulations through the California Department of Fish and Wildlife.

Trip Planning Tips

The nearest major airport to Mammoth Lakes, California is the Reno-Tahoe Airport in Nevada. If you travel to LAX, you are looking at a five hour car journey to reach your destination. Luckily, you will be driving through Central California, so you are guaranteed a scenic trip.

The Mammoth Inn offers rustic accommodations and close proximity to the San Joaquin River. This is a popular choice for skiers and snowboarding enthusiasts. You can enjoy a free breakfast before taking the complimentary shuttle to the Village to explore. 

Outdoor lovers might have a better time staying at one of the area’s many campgrounds. Twin Lakes Campground offers lakeside camping with breathtaking views that will make you forget how close you are to the town of Mammoth Lakes’ amenities. 

It might take you a lifetime to truly feel like you’ve conquered the San Joaquin River, so you might as well start with the South Fork. And from there, who knows?

Looking for more places to fish? Check out our DIY Guide to Fly Fishing California

Feature image by Duanerh