Big Break is a small bay or estuary located at the edge of the San Joaquin River within the Sacramento-San Joaquin River Delta near Oakley, California. This area is a tidal mixing zone where saltwater from the Pacific meets freshwater from the Sierra Nevada, creating an estuarine environment. The primary launch for paddlers is the Big Break Regional Shoreline. Access is via a paved, level path leading approximately a quarter-mile from a large public parking lot to a small, sheltered beach launch. The park provides free wheeled kayak carts from the Visitor Center to transport boats. A critical safety consideration is the significant tidal influence. The launch beach can become a broad expanse of deep, sticky mud at low tide, creating a serious hazard where individuals can become stuck. Paddlers must consult tide tables and plan their launch and return to coincide with mid-to-high tide stages to avoid this danger. The park offers naturalist-led kayak programs and has restrooms near the parking lot and launch site. The surrounding landscape features tidal sloughs, freshwater marshes, and riparian areas, supporting a diverse array of wildlife including great blue herons, egrets, river otters, and Western pond turtles. The area is known for exceptional bird watching. The water body itself is part of the vast Delta network, allowing for exploration of nearby islands and shorelines. Given its location on the Delta, paddlers should be prepared for wind exposure across open water and should anticipate potential boat traffic from the adjacent San Joaquin River channel.