Back in June of last year we had the opportunity to help out the folks at Lake Stockholm, New Jersey return their dry fire hydrant to working order. While this may not seem like a big deal to some it was a huge deal at the time because the DFH had to be working in order for the lake association folks to host a special swim event. Without the working DFH, no permit for the event. With help from the association leadership and a local diver, we were able to repair the DFH and get the folks their event permit.
The problem with the DFH was a common one for older installations...fish living in the pipe because the strainer holes were too big. With fish in the pipe and no means to back flush the system, the fish then block the suction head when the FD takes suction and flow is restricted or completely blocked. The tough part was replacing a glued-PVC strainer underwater. Fortunately, we were able to replace the old strainer with a new, ETT 6-inch horizontal barrel strainer with back flush flap. The replacement required a diver to use a HyMax repair coupling...which ended up being much easier than anticipated.
With the system back in operation, the permit was obtained and the swim event a success. Later in the summer the association folks completed the upgrade by installing a new suction head.