Rats in the compost bin

My allotment is above the river and rats have always been around but this last year their presence became a problem.

I used metal bins for the bird seed and chicken wire to close off where they gnawed the shed door, and finally poisons (found three large dead adults) and the population has dropped. I set rat traps in the runs that weren’t sprung. I no longer put vegetable trimmings in the compost bin.  I did find runs through the pallet compost bins and noticed the loss of the amphibians that lived there. I now take my cat with me to the allotment and she is a good presence, though I believe small rodents are more her forte. 

The Gardeners World article mentions not using compost that had rats in it on edible crops, I’m assuming as a mulch.  What about using it as a soil conditioner or a top dress?  If used as a top dress on herbaceous beds, will this attract rats?

 I also have a new pond; is it possible to prevent rats here? 

And I will seek out snake poo, as learned from another thread.