This is a topic I am borderline obsessed about, and the broader picture is that most of our water comes from the Colorado River and most of it goes to agriculture (eg, not to the homes of people like you and I). So like many things, there is only so much we can do as individuals.
I have had Brad's books for years and what I can tell you from practical experience is that all of that information is good and important, but it just rains so infrequently.
We simply must concentrate our efforts on using less of the imported water OR using it twice.
If you use native plants for landscaping then yes, rainwater can sustain that. And that's a very worthy goal especially if stormwater drains
away from your property. You definitely want everything that falls from the sky to sink into your land and be used.
Perhaps a good place to start is to simply
read our water bills and understand what we're using currently, and how we can lower it. The old "what gets measured gets managed" thing. I think the average person uses about 100 gallons per day.
So as not to be exhausting here are 3 changes I made in my life to improve:
- "Laundry to landscape" piping. My washing machine water now goes to a shallow basin in the yard around some trees, to get used a second time.
- Showers instead of baths. And I take short showers and will turn the water off mid shower to lather or give hair products time. (Extra points for outdoor showers near a tree)
- Hose timers on every hose. I've forgotten a hose too many times and that wastes a lot of water each time. Leaks and accidents are the worst.
There is another thing we could all do that nobody really talks about, which is
use less electricity. I think my APS electricity comes from Palo Verde Nuclear plant which ... now I am trying to find the numbers and the website I saw last is eluding me. It was something like
750 gallons per 1,000 kwh that was used to create the electricity.
A typical Phoenix single family home can easily use several thousand kwh in a summer month with the A/C running. The reason that cities don't talk about this is, I think, because if you save electricity and therefore water, it didn't come from your city's water budget. Therefore they don't get to pat their own selves on the back. But the point stands,
less electricity = less water used.