Local Surge Pressures Inside Pump House

There has to be an expert out there, but from basics the relevant points would include:

- there is bound to be reference or standard somewhere that applies

- on the survive side of the equation, any valve/pipe must be able to handle whatever the calculated peak pressure is, with some level of safety expressed in a safety factor,

- on the force/supply side of the equation, the peak pressure (short of "water hammer') will be a function of the mass of the liquid column being stopped, times its velocity and inversely to the time the stop process takes. This is a conservation of momentum issue.

If the supply pipe is elastic (or not straight and has bends) then it will stretch/move and the "stop" time will increase and the "peak" pressure will decrease. A worst case calculation would take the supply pipe as "rigid".

- If things are forced to happen very quickly, as in a valve slams shut, then the forces become more transient/complex because pressure waves are reflected back and forth - and for example, the "leading" edge of the column of liquid will be "stopped" before the "trailing" edge of liquid is has received any pressure signal back to slow its progress.

If you are talking about pressure arising out of pump failure, then they will be relatively modest compared to (say) slamming a valve shut if the pump is any of the fan/impeller type - and I would have thought that having to allow for surge arising out of quick shut-off on the delivery side would dominate anything arising from simple pump failure.