How slow is slow? Managing fire hydrant operation for protecting water infrastructure

There have been several water main breaks attributed to fire hydrant operations despite the persistent guidance from stakeholders to operate the hydrants “slowly.” Traditional water hammer simulations for determining the safe operational times for every hydrant can be tedious and impractical for most water utilities. While the rapid operation of certain hydrants can generate excessive pressures, most hydrants are benign and do not generate pressures capable of bursting water mains. Using certain simplified water hammer parameters, the authors propose automated methods that can identify benign hydrants at least 100 times faster than the traditional methods where the operation of each hydrant is simulated by manually modifying the baseline models. Detailed analysis with more accurate data can then be performed to determine the precise operational times for the critical hydrants and develop the necessary measures to safeguard their operation.