Some IT expert...?
Yes you can destroy a pump by turning it off and on again. I'm sure he's capable of talking to a pump expert, and finding out these things.
I can think of many easy ways to break a pump from a remote controller.
Pump motors are designed not to be started too often. Usually they're set up not to be able to start more than 12 times an hour. This is either enforced in software, or often a run-on timer that runs the motor for a set time. Thus, after a start, the pump will idle until it's needed again, or the timer runs out. Bypassing these controls, and constantly re-starting the motors would break them.
If you could get sufficient control of a water supplier's systems you could cause some interesting explosions in the pipework. Water is heavy, and under tens of atmospheres of pressure you can do some serious damage with it. They're possibly lucky they're only having to replace a burnt-out pump motor.