Paving and rainfall

[Stephen Tashiro]

I've heard that one way to increase the rainfall on grass is to pave parts of the lawn. The water that would have fallen on the paved part runs off to the unpaved part. This sounds reasonable to me since I notice that vegetation here in southwest NM grows better around sidewalks and rocks than out in the open.

Of course, the paving should be something like brick or stone that will look nice. But is there any known science about how it should be spaced? Water running off a large area like a parking lot will only go so far off the edge. If one were doing paving purely for ornamental and irrigation purposes, how should the paving be spaced?

[Ted Calver]

Lots of science on this topic-- but on a much larger scale. Here's a place to start if you are mathematically inclined.

http://www.lmnoeng.com/Hydrology/hydrology.htm

[Stephen Tashiro]

Thanks Ted. I'm glad I was a math major!

[Al Wasser]

If you can find someone that is into "permaculture" they might be of some help, or perhaps a book on the subject. Whatever you plant using rock or rocks over plastic would have to able to tolerate prolonged periods of drought like you get there.

Next time you drive the highways, keep an eye on what is growing next to the edge of the pavement. It is a lot different mix of species than you get just a few feet from the edge of the pavement. I worked in NM for about 20 yrs. with the USFS so I am familiar with your climate.