Can I turn off the electric and cut the cable to an outside unused pond pump?

[Mary W]

We had two ponds with a pump circulating water between them but the balance was never right and the bottom one was constantly running low. We filled it in and just have one now which is fine but I still have the filter box which I want to get rid of. It was properly installed and the cable runs into an outside box on the house wall. If I turn off the electricity can I cut this cable safely?

 

[bernardgreen]

If I turn off the electricity can I cut this cable safely?

Probably but you may trip an RCD ( Earth to Neutral as you cut the cable )

BUT what will happen when yo turn the power back on. The cut end will become Live. At least put the three wres into three separate terminal blocks in a suitable enclosure.

Better to disconnect the cable at the outside box on the wall. ( with the power OFF )

 

[John D v2.0]

You need to properly isolate the system before doing any work on the circuit.
Then disconnect the cable properly at the source if at all possible, and certainly don't rely on just a switch to keep it safe after the work. Your polarity should be correct, but in fact if it's reversed at any point before the switch, the cable could still be live while switched off.
If you can't disconnect at the head follow the previous poster's advice about terminating the cable into a suitable enclosure.