The Bylaws, rules in England restrict us from placing irrigation below ground i.e.(popup sprinklers) from a house tap supply, the reason for this is ground water (contaminated pesticides weed killer- could be syphoned back to the drinking supply within your dwelling.
Highley unlikely, and yes with a double non return valve fitted to water supply, problem solved, still its words for thought.
Pumps systems and tanks are necessary, generally due to the size of the irrigating area and whether you use popup sprinklers, as they require high pressure to work and the number of popups that can run simultaneously.
The tanks systems (show below) are timed to run for no more than 5 minutes a circuit morning and night, and pumping litres very quickly and efficiently.
This irrigation installation had the advantage of installing a 1000 litre ground tank, it was a neat finish all hidden under the patio
