Cache Slough is a tidal waterway in California's Sacramento-San Joaquin Delta, functioning as the deepwater shipping channel leading to Sacramento. A primary access point for paddlers is the area just north of Rio Vista, where launches occur from the shoreline. This slough is part of the larger Cache Slough Complex, a network of tidal wetlands and sloughs characterized by winding channels, tule reed marshes, and floodplains. The paddling environment is largely undeveloped and remote, with scenery along the main channel described as unvaried, but it provides access to more intimate side sloughs like Miner Slough and Steamboat Slough. These adjacent waterways feature cottonwood and eucalyptus trees, blackberry bushes, and offer a more secluded experience.

Tidal influence is significant, with a typical high tide range around 3 to 3.5 feet. Paddlers use the incoming tide to assist travel north from Rio Vista, and the outgoing tide to assist the return south, indicating strong currents that must be planned for. The area is exposed to wind, which can frequently blow from the northwest at 10-15 mph with higher gusts, creating choppy conditions especially over the long, open fetch of the main shipping channel. This same channel also carries commercial barge and ship traffic, which is a major hazard; routes often require crossing this active channel to reach other sloughs. Facilities are limited, with developed launch ramps and docks found at nearby county parks like Hogback Island, which has picnic areas and restrooms but no gentle beaches for landing.

The complex supports rich wildlife, including great blue herons and egrets, and is a critical habitat for migratory birds on the Pacific Flyway. Paddlers may encounter flooded historical sites, such as remnants on Prospect Island, and areas like the Lindsey Slough Restoration Project. Water quality has been a focus of environmental study and restoration due to its role as habitat for endangered fish species. The overall experience is one of a working, tidal delta landscape where trip success depends heavily on timing tides, watching for wind, and being vigilant for large vessel traffic.