Franks Tract State Recreation Area
California

Franks Tract State Recreation Area

Available Activities
  • Camping
  • Fishing
  • Boating
  • Wildlife Watching
  • kayaking-canoeing
  • wildlife-viewing
  • Biking
  • Historic Sites

🌊 The Drowned Island — California’s Underwater State Park Where Bass Hide in Sunken Fields — Franks Tract State Recreation Area in the Sacramento-San Joaquin Delta, California, submerged island, legendary bass fishing, striped bass, largemouth bass, kayaking through flooded farmland, tule marsh labyrinth, levee-break island, boating — Contra Costa County, CA

There’s a state park in California that’s underwater. Franks Tract was a farming island in the Sacramento-San Joaquin Delta until the levees broke in 1938. The farmland flooded. The fields sank. And what emerged was one of the most unique fishing destinations in America — 3,400 acres of submerged island where largemouth bass hide in the tules and striped bass patrol the channels.

You can’t walk here. You can only float. There are no trails, no campgrounds, no visitor center. Just water, tule marsh, and the submerged remains of a farming community swallowed by the delta. Kayakers paddle through corridors of tule. Bass anglers cast into flooded ditches. And the geography below your boat is an entire island — roads, fences, foundations — all underwater.

What to Do

ActivityDetails
Bass FishingFranks Tract is legendary for largemouth bass — the flooded tule edges, submerged vegetation, and shallow water create ideal habitat. Fish flip into the tules. Use weedless frogs, jigs, and Texas-rigged plastics. The bass here can exceed 10 pounds. Tournament anglers train on this water
Striped BassStriped bass migrate through the delta channels around Franks Tract — seasonal runs bring big fish from San Francisco Bay inland. Troll or drift with cut bait. The striper fishing peaks in spring and fall. Fish over 30 pounds are caught here annually
KayakingPaddle through the tule corridors — narrow channels through walls of marsh grass, opening into flooded fields where you can see the bottom (old farmland) below your kayak. The experience is surreal — floating over a sunken island, watching herons and egrets rise from the tules
BoatingAccessible by boat from numerous delta marinas and launches. The interior of Franks Tract is shallow — use caution with prop depth. The channels around the perimeter are deeper and navigable. A trolling motor is ideal for the interior
WildlifeThe tule marsh supports great blue herons, great egrets, black-crowned night herons, river otters, and beaver. The flooded island is a wildlife refuge by accident — when the farm died, the wetland returned. Nature reclaimed what humans abandoned

The Delta

FeatureDetails
The Great FloodIn 1938, heavy rains and tidal pressure broke the levees surrounding Franks Tract. The island flooded. Unlike most delta levee breaks, this one was never repaired. The farming community was abandoned. The water stayed. A state park was born from catastrophe
Sacramento DeltaThe Sacramento-San Joaquin Delta is California’s liquid infrastructure — 1,100 miles of waterways, 700,000 acres of islands, and the water supply for 25 million Californians. Franks Tract is one of many delta islands, but the only one that became a state park by drowning
Water OnlyNo land access. No facilities. No dry ground except remnant levee fragments. Access by boat from Bethel Island, Discovery Bay, or other delta launches. This is the only California state park you literally cannot walk on
Tule MarshesThe tules (bulrush) have colonized the shallow waters — creating a labyrinth of channels, openings, and dead ends. Navigation requires attention. GPS helps. But getting slightly lost in the tules is part of the experience — and the best way to find bass

Best Time to Visit

SeasonBest For
Spring (Mar–May)🎣 Largemouth bass spawning. Striped bass migration. Wildest fishing. Tules greening. Warm days, cool mornings
Fall (Sep–Nov)🐟 Bass feeding up for winter. Striper run. Delta at its clearest. Comfortable temperatures. Tournament season
Summer (Jun–Aug)Early morning topwater bass. Hot by midday. Delta breeze afternoon. Good fishing at dawn and dusk
Winter (Dec–Feb)Striper season. Bass slower. Delta cold and foggy — classic Central Valley tule fog. Atmospheric but challenging

Frequently Asked Questions

Can I visit without a boat?

No — Franks Tract is completely surrounded by water. There is no land access. You need a boat, kayak, or canoe to reach the park. Marina rentals are available at Bethel Island and nearby delta locations.

Is it safe to navigate inside?

Yes, with caution. The interior is shallow — 3 to 6 feet in most areas. Watch for submerged objects (old fence posts, pilings). Use a trolling motor or paddle. The perimeter channels are deeper. Bring a map or GPS — the tule corridors can be disorienting.

🌊 A Sunken Island. A Tule Labyrinth. And Bass That Hide Where Farms Used to Be.

The levees broke in 1938. The farm drowned. The tules grew back. And now 3,400 acres of submerged island produce some of the best bass fishing in California. You can’t walk here. You can only float — over roads, fences, and fields that nobody has farmed in 86 years.

🗺️ Official Park Page

Sarah Mitchell

About the Author

Outdoor Editor & Trail Expert

Sarah Mitchell is an outdoor writer and trail researcher with over 8 years of experience exploring state parks across America. As the lead editor at AmericasStateParks.org, she has personally visited more than 200 parks in 42 states, logging thousands of trail miles and hundreds of campground nights. Sarah specializes in detailed park guides, accessibility information, and family-friendly outdoor planning. Her work focuses on helping first-time visitors feel confident and well-prepared for their state park adventures.

200+ state parks visited across 42 states | 8+ years of outdoor writing

Last updated: April 27, 2026

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