Monday, April 26, 2010
One of the most interesting parts of permaculture is how they manage rainwater compared to the typical house.
Typically, and especially around Denver, your yard is shaped and landscaped to get rainwater that is coming off of the roof away from the house and off the property as fast as possible.
That makes a certain amount of sense. The builder really does not want water getting into the basement or hanging around the foundation too long because that can cause damage he would get sued for. Colorado has expansive soil with lots of clay that tends to expand if there is water around to hang on to.
And until recently there were laws in place that restricted rainwater harvesting, i.e. no rainbarrels. So the water could go to the Colorado River and on to California.
But there wasn't anything that required the rain to run off, it could mosey if you did it right. One of the big concepts of permaculture is to slow the rainwater runoff down and let it sink into the ground where the plants can get to it over time. This way you make the land itself drought resistant.
Next time it rains go outside and really look at where the runoff goes. Especially from your gutters and hardscapes like the sidewalk and driveway. If you really want to go nuts you can make a topographic map of your yard.
Where does it go to the street or neighbors yards?
Is there room at the bottoms of the downspouts for a raingarden to absorb some of that water that is not too close to the house?
Where could you put a set of small swales to make the water zigzag across your property to slow it down before it leaves your property?