I recently moved to Yakima, Washington where we, in the city, have separate water systems for potable and irrigation (most heavily irrigated valley in the US).

I had someone come out in the fall to blow out the system and the guy did a great job. However, I saw no need to pay someone to simply turn the system on (aka flip the input valve and plug the pump back in). i thus simply did those steps myself and the system started to work. However, the flow seems 1) a big less than when it was working good in the fall and 2) sometimes as it switches between zones the flow seems to go to almost nothing (barely enough to get the heads to pop up. Even manually opening the valve in question at the valve box doesn't change things.

Any ideas?? Pump seems to be turning great and was working fine when it was fall!