Help with nozzle inches using water meter

post by Gerardv514 on Jun 18, 2022

Hello all, I know there has been talk around here about one way to get a nozzle inch measurement, is to use your water meter and zone size.

I know roughly how long it takes to get about a half inch of water down, so I’ve used that to gauge how many inches are in an hour.

I’d like to just try the water meter way to see how close both figures are. I can use the water meter to see how many gallons are used in a certain amount of time for one zone.

What is the formula that I can plug my numbers into?

post by BobBlackmun on Jun 20, 2022

A = Area in Sq. ft.

C = Cu. In. req’d for 1 in. watering: A x 144

G = Gal. for 1 in. watering: C / 231

F = flow rate in gal. / hr. (from water meter – by zone if possible by running each zone for time period and observing gallons used)

I = in. hr.: F / G: (flow rate / gal. hr.)

post by Gerardv514 on Jun 21, 2022

Regarding measuring the area for squat foot, do you just measure what that one zone covers? What about a zone that overlaps another?

post by Thomas_Lerman on Jun 21, 2022

Personally, I measured between the zones. Theoretically, all heads spray to the next head. So, I measure between the heads of the zones.

post by BobBlackmun on Jun 22, 2022

I was fortunate to have the original irrigation system plan that included the zone areas. I did re-measure the two zones that include nozzles that overlap the other zone, and split the overlap areas in calculating the zone areas.

• Calculate inches per hour from water meter

post by championc on Jun 22, 2022

EDITED
(Water Used [gallons] ÷ Area [square feet] ÷ Mins duration [of the test]) * 60 [mins - to get hourly rate]
Apart from using the Rachio Yard Map to measure a zone, you can use the following tool.