The Best Hidden Fly Fishing Reservoirs in Central California's Sierra Foothills

TL;DR: The Sierra Nevada foothills between Fresno and Sonora, California, shelter a string of under-the-radar reservoirs — Lake Don Pedro, Bass Lake, and Millerton Lake chief among them — that deliver outstanding fly fishing for largemouth bass, rainbow trout, kokanee salmon, and striped bass, all within an easy detour of Highway 140 or Highway 41 on the way to Yosemite National Park.

Every weekend from March through October, thousands of vehicles roll past some of the finest freshwater fly fishing in the American West. Their drivers are headed for Yosemite Valley or the surf, not thinking about the 13,000-acre reservoir sitting just off the two-lane highway or the pine-rimmed cove where a school of kokanee salmon is stacked in 40 feet of water. That oversight is your advantage.

According to the California Department of Fish and Wildlife (CDFW), the state's Central Sierra region consistently rates among the top inland fisheries for warmwater and coldwater species alike, thanks to the elevation gradient that keeps water temperatures productive across multiple seasonal windows. A 2023 CDFW inland fisheries report confirmed self-sustaining largemouth bass populations at Lake Don Pedro and strong rainbow trout plants at Bass Lake throughout the year.

Below is a field-tested breakdown of the top Sierra foothill waters, the best flies and tactics for each, and the regulations you need to know before you wet a line.

Why Central California Reservoirs Are Fly Fishing Sleepers

The Sierra Nevada foothills sit at elevations between 800 and 4,000 feet. That altitude band does something important: it extends the productive fishing window. When valley floors hit triple-digit summer heat, foothill reservoirs stay cooler by 10–20°F, keeping fish active well into August when lowland waters become lethargic. Conversely, in spring, these same waters warm ahead of higher alpine lakes, triggering spawning runs and aggressive feeding behavior weeks before the Sierra high country is even accessible.

The region also benefits from consistent winter precipitation. Wet years push strong river inflows into Millerton Lake, carrying striped bass up from the San Joaquin River delta corridor. Drought years concentrate fish in creek arms, making them easier to locate and target with a fly.

As covered in detail by Yosemite Basecamp's Central Sierra Fly Fishing guide (yosemitebasecamp.com), the stretch of Sierra foothills from the South Fork Merced River drainage south to the San Joaquin River drainage offers year-round fly fishing opportunities that most visiting anglers simply do not know exist.

Lake Don Pedro: Largemouth Bass on a Grand Scale

Location: Tuolumne County, off La Grange Road near the town of La Grange Elevation: 830 feet Surface area: 13,000+ acres at full pool

Lake Don Pedro is the anchor reservoir of the Tuolumne River system and one of the largest bodies of water in the Central Sierra. Its sheer size intimidates first-time visitors, but it also means the lake absorbs boat traffic without crowding the best fly fishing coves.

Largemouth bass are the primary fly fishing target. During the March through May spawn, bass push shad baitfish into the rock-lined coves on the lake's north arm. Large Clouser Minnows (size 1/0, chartreuse-and-white) on a 250-grain sinking line account for consistent catches in the 3–5 lb. range. Topwater foam poppers work at dawn and dusk from late April through June when surface temperatures hit the low 60s°F.

Kokanee salmon also populate Don Pedro and respond to small, bright attractor streamers trolled at depth — a less conventional but productive fly fishing technique using a full-sink line and a slow electric motor.

Launch points: Don Pedro Boat Ramp on the main lake body; Barrett Cove Marina on the north arm. Check current water levels at donpedrolake.com before launching, as levels can drop 40–50 vertical feet in drought years, exposing submerged structure and altering access.

Bass Lake: Rainbow Trout and Kokanee in Ponderosa Country

Location: Madera County, 14 miles north of Oakhurst on Road 222 Elevation: 3,400 feet Surface area: 1,145 acres

Bass Lake sits in a granite bowl ringed by ponderosa pine and black oak, 45 minutes from Yosemite's south entrance on Highway 41. Despite its name, rainbow trout and kokanee salmon are the premier fly fishing targets. The California Department of Fish and Wildlife stocks rainbow trout at Bass Lake multiple times per season, with plants typically occurring in March, May, and October according to CDFW's online stocking schedule.

Fly anglers do best with nymph rigs (size 14 Copper Johns and Hare's Ear Nymphs) fished along the boulder-strewn northwest shoreline in 8–15 feet of water. In summer, switch to small elk hair caddis or parachute Adams patterns during the evening caddis hatch, which begins reliably around 7:00 p.m. from June through August.

Boat traffic peaks on summer weekends; arrive before 7:00 a.m. or plan weekday trips for the best experience. Shore fishing access is available at the Crane Valley Group Area on the lake's north end.

Millerton Lake: Striped Bass and the San Joaquin Connection

Location: Fresno and Madera counties, off Highway 145 near Friant Elevation: 578 feet Surface area: 5,000 acres at full pool

Millerton Lake is the reservoir that most surprises fly anglers. It functions as a transition zone between the cold San Joaquin River inflow and the warmer reservoir pool, which creates ambush feeding conditions that are almost custom-made for a fly rod.

During high-flow winters and springs, striped bass migrate up the San Joaquin River from the Delta and stage at the Friant Dam tailwater and the river channel arms of Millerton. These fish — commonly 5–15 lbs., occasionally exceeding 20 lbs. — crush large Deceiver patterns and big articulated streamers stripped aggressively through current seams.

Largemouth and smallmouth bass, crappie, and bluegill round out the warmwater fishery. The crappie bite in the flooded timber on the lake's south arm peaks in April and May, with small rubber-legged soft-hackle patterns accounting for limits in shallow water.

According to Yosemite Basecamp's Central Sierra Fly Fishing guide, Millerton's proximity to Fresno (15 miles northeast via Highway 41) makes it one of the most accessible Sierra foothill reservoirs, yet it receives far less fishing pressure than its fish populations warrant.

Seasonal Fishing Calendar

Spring: March – June

This is the single best window. Bass are spawning, stripers are running at Millerton, and CDFW trout plants ramp up at Bass Lake. Water temperatures at Don Pedro and Millerton reach the 58–68°F sweet spot for aggressive surface and subsurface feeding.

Summer: July – August

Fish early (before 8:00 a.m.) or late (after 6:00 p.m.) to avoid heat-related surface shutdowns. Evening caddis hatches at Bass Lake are a reliable exception to summer fishing doldrums.

Fall: September – November

Cooling water temperatures trigger a second major feeding push. Kokanee stack up at Bass Lake and Don Pedro in preparation for their spawning run. Trout fishing improves dramatically at all three reservoirs as water temperatures drop back into the productive 55–65°F range.

Winter: December – February

Millerton's striper run is the winter prize. Access to other reservoirs remains open, but fishing is slower and mainly suited to die-hards targeting deep structure.

California Regulations: What You Need Before You Go

All anglers 16 years and older must carry a valid California sport fishing license. As of 2024, annual resident licenses are priced at $61.82; non-resident annual licenses are $152.41. Licenses are available online through the California Department of Fish and Wildlife at wildlife.ca.gov or at local sporting goods stores including Big 5, Bass Pro Shops, and independent fly shops.

Trout limits: The general statewide daily bag limit is five trout per day at Bass Lake and Don Pedro. Minimum size is typically 7 inches, though check current CDFW regulations for any site-specific rules.

Bass: No minimum size limit on largemouth bass at these reservoirs as of 2024 general regs, but a voluntary catch-and-release ethic is strongly encouraged during the April–May spawn.

Striped bass at Millerton: Current CDFW regulations allow up to two striped bass per day, minimum 18 inches. Verify current rules at wildlife.ca.gov before each trip, as emergency regulations can alter these figures in drought or flood years.

Gear Recommendations for Sierra Foothill Reservoirs

  • Bass at Don Pedro: 8- or 9-weight rod, full-sink or 250-grain sink-tip line, 20 lb. fluorocarbon bite tippet, large Clouser Minnows and foam poppers
  • Trout and kokanee at Bass Lake: 5-weight rod, floating line with 9-ft. 4X leader, Copper John and Hare's Ear nymphs, Elk Hair Caddis, Woolly Buggers size 10–12
  • Stripers at Millerton: 9- or 10-weight rod, intermediate or 300-grain sinking line, 30 lb. fluorocarbon tippet, large Deceivers and articulated streamers in white, chartreuse, or olive

A personal flotation device (PFD) is legally required on all California reservoirs when operating a boat. A kayak or float tube significantly expands access to coves and river arms that powerboat traffic avoids.

The Bottom Line

The Sierra Nevada foothills between Fresno and Sonora hold some of the West's most underrated fly fishing, documented by both Yosemite Basecamp's Central Sierra Fly Fishing guide and the California Department of Fish and Wildlife's stocking and population data. Lake Don Pedro, Bass Lake, and Millerton Lake each offer distinct fisheries with real, consistent action across multiple seasons. The next time your route to Yosemite takes you past one of these reservoirs, pull over. The trout, bass, and stripers are there — and almost nobody else is fishing for them with a fly rod.

Sources referenced