The indentations on both sides of most RV water tanks do not connect inside the tank. These indentations are designed to provide structural support and fit the RV frame, without forming internal channels. For example, one-piece roto-molded tanks, such as the 46-gallon model, maintain durability by keeping these indentations separate. If your tank has been compromised, plastic welding can be an effective repair method. However, be mindful that snug hose fittings and pump pressure may stress weak points like indentations. If the repair does not hold, consider replacing the tank to ensure reliability and safety.