PipeDown wrote:
"grodenhiATgmailDOTcom" wrote in message
oups.com...

We have a RainBird sprinkler system installed for lawn irrigation and I
was wondering ABOUT how long to run each zone to get 3/4 - 1 inch of
water. I know there's a ton of variables (water pressure, head type,
etc). But I'm looking where to start with the typical rotary (non
impact) head (T-Bird) doing a 180 degree sweep. My house has "normal"
water pressure and there are 4 heads/zone.



Really, the only reliable way to test the system is to set out a grid of
paper cups and run it for 30 min then adjust as required. If you find it
uneven, you can adjust each head but that's unnessary if they are all close.

Reduce watering weekly until the grass shows stress than increase slightly
and leave it there





RainBird publishes watering rates for a variety of pressures for each of
its spray heads on its web site

Rate per triangle and rate per square.

The BIG commercial sprinklers such as you see on a golf course (100 ft
circle typical) water at about 0.5 gal per sq ft per hour. That's 14
gallons per minute per spray head.