Lawn, yard, whatever. That's semantics. It's a half acre of whatever. You're trying to get 13,000+ gallons of crystal clear potable water onto it (and further wasting a ton in the process through evaporation as evident by the significant temperature drop). All because you want your shrubs to look nice and climate change is going to make that a non-starter. I guess you want a pat on the back for doing 30% better than horrible people. Congrats?
In California, new development requires demonstrated water capacity. When you're asked to conserve water, it's not so the rivers and lakes can be allowed to flow more freely - it's so there's enough capacity for town/county councils to get approval for new condo developments and housing tracts. I'd rather use that water for something else, even if it means just draining it into the ground. Some might say California agriculture needs the water, but growing more oranges for China and making more jobs for people who aren't even in the country legally isn't high on my priority list. Don't get me up on a soap box.
In any event. If you don't want to xeriscape (too a greater extent than maybe you are), consider spending a whole Saturday that month you need to water walking around with your hose and flood irrigating (no nozzle), applying the water directly to the soil in lieu of applying it in the least efficient way possible (spraying it willy-nilly through the air).
It would take 22 man hours of watering by hand without counting bathroom breaks, meals, other responsibilities, etc., and the yard is 100% xeriscape. Some people think that means it doesn't need water. That's false. It just needs much less than grass or weeds you buy in pots at the local hardware store, but it still needs
somewater. I think perhaps some people here don't realize that it's only rained once here in the last year in any meaningful amount. Once. Even cactus needs more water than that.
The lawn that was here when I bought the house would have required about 200,000 gallons per year to maintain. Now that I use 33,000 gallons in a severe drought year, and 0 in normal (or even 'light' drought years) is A-ok. I'll start doing more when everyone else starts using as little as I do.