By Mark van der Feyst
A problem that can arise when using a dry barrel hydrant is the operating stem breaking. The operating stem connects the main valve below ground to the stem nut on top of the hydrant.
Excessive pressure exerted on the operating stem can cause it to snap due to cold weather, old age, poor maintenance or just too much force being used. When the operating stem breaks, the hydrant is out of service, and depending upon which position the main valve is in, the hydrant will either be stuck open or closed.
If the hydrant is stuck closed, there is no real problem. But if it is stuck open, we will have nonstop water flowing.
When supply lines are attached from the hydrant to the apparatus pump intake and the hydrant is stuck open, the apparatus is now committed to the hydrant — there is no way of taking the hose off safely.
One method to alleviate this problem is to use gate valves on the hydrant discharges. Whether you are using a 2½-, 4- or a 5-inch supply line, attach a gate valve first, and then attach the supply line to it. This will allow you to safely isolate a hose line for removal in case the hydrant becomes stuck open.