55-gallon drums are often used in as water storage barrels in rain harvesting projects. Those who wish to collect and store more than 55 gallons of rainwater may choose to use bigger storage tanks or to use multiple 55-gallon drums connected together. This type of water storage can be done as a do-it-yourself project with a few basic plumbing supplies and tools by someone who has some basic plumbing skills.
Cut and thread one-inch holes an inch from the bottom on the 55-gallon drums using a hole saw and a one-inch pipe thread, a device used by plumbers to cut threads into a hole. A plumber may be required for those who do not have access to a pipe thread.
Coat one-inch PVC male connectors with silicone and screw into threaded holes cut into drums. Once dried the silicon will keep the drums from leaking.
Set the drums in a straight line next to one another in the place set aside for the drums.
Cut one-inch PVC pipe into three-inch lengths to match the number of 55-gallon drums being connected.
Apply primer and PVC glue to three-inch lengths of pipe and insert into male connector in drums.
Apply primer and glue to PVC T connectors and glue the top of the T connection to the sections of three-inch PVC proceeding from the drums. Connect an elbow to one of the drums on the end. The T connectors will be used to connect the drums.
Cut sections of one-inch PVC pipe to a length equal to the width of the drums plus two inches. The number of sections of pipe will be dependent on the number of drums being connected, one section of pipe for every two barrels.
Apply primer and glue and connect the sections of pipes to the T connections and to the elbow connection on the end of the drum system.
Apply primer and glue and connect a PVC ball valve to the end of the PVC pipes connected to the Ts, opposite the end with the elbow connector.