Patrol Boat, River (also referred to as Pibber), or PBR, is the United States Navy designation for a small rigid-hulled patrol boat used in the Vietnam War from March 1966 until the end of 1971. They were deployed in a force that grew to 250 boats, the most common craft in the River Patrol Force, Task Force 116, and were used to stop and search river traffic in areas such as the Mekong Delta, the Rung Sat Special Zone, the Saigon River and in I Corps, in the area assigned to Task Force Clearwater, in an attempt to disrupt weapons shipments. In this role they frequently became involved in firefights with enemy soldiers on boats and on the shore. PBRs were also used to insert and extract Navy SEAL teams. They were also employed by the United States Army's 458th Transportation Company, known as the 458th Seatigers.
PBRs were operating with the U.S. Navy Reserves up until 1995 at Mare Island, California prior to the base's closure that year. During the Vietnam War, Mare Island was home to the U.S. Navy's Repair Facilities, Mothballing Operations, Submarine Operations, and Riverine Training Operations for both Swift Boats and PBRs.
The training areas for the PBRs and Swift Boats still exist today within the "Napa-Sonoma Marshes State Wildlife Area". Sloughs such as Dutchman Slough, China Slough, Napa Slough, Devil's Slough, Susiun marshland and the Napa River all run through the former training area.
In the late 1990s, what remained of the U.S. Navy PBR force (Swift Boats had been retired from the U.S. Navy immediately following the Vietnam War during the early 1970s) was moved further inland towards Sacramento (State Capital), California, which is also intertwined with rivers. From Sacramento, PBRs can still transit directly to and through San Francisco Bay and into the Pacific Ocean, if need be. The waters of the State Wildlife Area, next to the former U.S. Navy (Riverine) training base at Mare Island, are still available for U.S. Navy PBR usage.