Here's my plan - all the parts. I will use a 12" riser because 1) the heads were buried pretty deep and, 2) I need the new shut-off valve to end up above ground: Here's a closeup of the bottom connection. The tee at the supply line is a 3/4" male connection: Here's a closeup of the shut-off valve connection. Shut-off valves are $3.17 each at Lowes. What a bargain!: Will this work like I hope? Thanks! Carol This post was edited by love_the_yard on Thu, May 2, 13 at 14:07

amg. Your description is little confusing to me. There are differences in parts to each brand of sprinkler, for example nozzles. The whole sprinkler head should be interchangeable where you have 1/2" pipe thread fittings for connecting the different brand heads. There are different flow rates for different types of heads even within the brands. You have to look at the flow rates and throw distances for certain pressures for any type of head you need. That is how you estimate the duration of irrigation. JMHO Aloha

the reason for two valves is to isolate the backflow assembly for testing. as far as shutting the system down to fix a leak either valve will work.

You might get more comments in the Irrigation forum. I've always had a problem with single point sprayers and the Rainbird type of sprinkler, because they shoot water out away and leave the center of the circle relatively dry. They can be adjusted, but they're too fiddly for me to figure out. The oscillator is the only sprinkler that gets close to uniform coverage. Several people have hinted that you would be better off with a different grass. What you have is a cool season, northern type grass, but you are located in a warm season location. You can make it work as long as you have unlimited water available, say, from your own well. You might be happier with a mix of prairie type grasses. Here is a picture of a lawn in Salt Lake City. Thanks to bpgreen for posting this several years ago. His lawn is a mix of wheatgrasses, blue grama, and strawberry clover. He only waters it a few times a year. Of course his temps are not as hot as yours, but then again, the varieties of wheatgrass he has are adapted to the cooler climes. You would be using something different. The grass itself does not grow fast, but it will send up seed heads and flowers on long stalks. Those can be mowed off every few weeks before they get up too tall. I guess the point is this looks like a real lawn and uses a fraction of the water used by traditional lawns.