Breaker Valves are common on pressurised irrigation systems to let air into the pipes when there is a pressure reduction to reduce the risk of soil being drawn back into the pipes. Even distribution of primary treated wastewater into trenches is best practice and a means of reducing the clogging effects at the start of trenches and getting better dillution of fresh toxic wastewater along the whole trench. If a pump is being used then how do we prevent siphoning of wastewater back out of higher trenches into lower trenches or back down into the pumpwell if the non-return valve leaks due to hair etc? A breaker valve up hill and only just before where the pumpline branches out to each trench should help prevent siphoning once the pump stops. Has anyone tried this or had a problem with it ? Do breaker valves gum up?