[jpepper]

My issue lies with when the sprinklers come on, there is a significant drop in water pressure in the sink, shower, etc. I checked the sprinkler lines and there are no obvious leaks (ie holes in the ground). Part II of my pressure problems is that there is no pressure in sprinkler zone 1 (sprinkler heads do not come up but dripple water), 1/2 pressure in sprinkler zone 2 (sprinkler head come up but are at 1/2 flow) and sprinkler zone 3 has full pressure. The sprinkler repair company wants to add a pressure regular to the line to the sprinklers (runs at over 100 psi when s/b be 75 psi) and split sprinker zone 1 into two zones due to the # of sprinkler heads on this zone). However this does not answer why sprinkler zone 2 is at 1/2 pressure. Ironically, the house was built in 2009 and for the past 5 years, including last year, the sprinklers ran fine with no water pressure drop problems. Any suggestions?

[Milo Dolezal]

Sprinkler line should Tee off from main line before main water line enters house. It appears to me that your sprinkler line is connected somewhere to a pipe that supplies house with water. Sprinklers have high water flow and they will drain all pressure from the house plumbing when turned ON. I suggest that you separate house and irrigation pipes.

Sprinklers should have water pressure not higher than 95 psi. If higher, install high-flow ( or high velocity ) pressure regulator. ( FYI: regular pressure regulators adjust water up to 75 psi, high velocity pressure regulators go higher... you want to have that option available if needed to adjust for higher pressure )

If your sprinklers don't have enough spray and you have 100 psi of pressure - than sprinkler pipes are most likely either undersized, sprinkler heads screens dirty, or anti-siphon valve is partially closed. But since you say you used to have good pressure until recently than undersized pipe should not apply.

Hope that helps

Milo