Rainwater is one of our society’s greatest forgotten urban resources. We design our developments to drain rainwater from our property turning streets in to rivers. From there, water is directed down storm drains and forgotten about. We’re literally letting billions of gallons of water drain away when much of it could be used to water our landscapes, beautify our neighborhoods, and reduce the heat island effect.

This past weekend I saw Brad Lancaster talk about rainwater harvesting at the Green Living Conference in Phoenix and was moved to start making some changes around my own house. He’s from Tucson and has transformed his house from basically an empty dirt lot to a desert oasis. He’s done all this by “planting” the rainwater in his yard and keeping it there for the plants and trees to use. Seeing his yard and what he’s done with his system of catching rainwater in a cistern, using gray water from his sinks, tub, and washing machine it sounds too overwhelming and expensive to do this yourself, and I was thinking “Yeah, if only I had the money.” He had some great advice though, start small and simple. That’s what I’m going to do today.

With one inch of rain there is 600 gallons of water for every 1000 Sq ft of land. I just looked up the Sq ft of my property and it is just over 5000 Sq ft. Where I live in the desert we average about 8 inches of rain a year which means over 24,000 gallons of water fall on our property a year. Unless you live in Yuma Arizona where they average 3 inches a year, you probably get more rain than the 8 inches I get. Lets see if we can make use of some of this and not let it all wash away.

First thing you should do is think about the last time it rained and where rainwater is collecting in your yard already. This should reveal some low spots that could be ideal for planting. In my yard I have one such low spot next to my house where water from the yard and roof drains to. Unsurprisingly this has turned out to be one of the easiest spots to grow anything in our yard. Now there is even catnip, lavender, sunflowers, and a little chamomile that planted themselves and are thriving.

Second take a look around and see what you already have planted. Is water able to flow to them when it rains? Is there a basin the water can fill to water the plant? In my yard I have a grapefruit tree with a little berm around it. This is pretty good to hold in water from the hose, but when it rains it blocks any water from filling it. This probably should have been obvious, but I never really thought about it. The tree also has not really grown much in the two years it’s been there, I think it’s pretty much been stunted. Maybe it hasn’t had enough water? This morning I pulled out the shovel and started digging out the berm and creating a basin instead. Ideally this should have been done when I planted it a couple years ago, but better late than never. I was careful while digging down because I didn’t want to disturb any roots. When you dig out the basin be sure to make it at least as wide as the branches so that it can collect any water dripping off the leaves. I wasn’t super aggressive with the digging out of the basin because I was worried about the roots, so hopefully it’s dug down enough. I’m a beginner myself, so I can’t wait to see how this works. I gave it a test run with the hose and it held dramatically more water than the berm ever did. I’ll have to do this with the rest of plants in the yard.

See! That was easy! Just these two ideas give you a good start at using the rainwater as a resource and reducing your usage of tap water to water your plants. To get more in depth with water harvesting pick up the book Rainwater Harvesting for Drylands by Brad Lancaster. He lives in Tucson Arizona and has done amazing things with his yard and neighborhood all without irrigating with tap water. Check out his website for some great before and after pictures of his yard [here]. You can also attend one of his lectures or classes he teaches on rainwater harvesting to get some hands on experience. A list of his upcomming events can be found on his website as well. [harvestingrainwater.com]