4 Myths About Water Harvesting in Dry Lands

Unless you’re a passionate water conservationist (or a hippie farmer), water harvesting may sound like some futuristic nonsense to you, especially if you’re wondering what water is available for harvesting in the desert or other dry climate.

Water harvesting does not just mean rainwater; graywater is any water generated in the home except water from toilets and the kitchen sink. 70% of our water usage goes to our landscapes but 50-80% of our graywater is reusable, so why pour perfectly good, potable water on your trees when they’ll appreciate used shower water just as much?

I’ve always been smitten with the idea of water harvesting so when I had a chance to take a class from Greg Peterson of The Urban Farm, I was thrilled. Greg cleared up a lot of my misconceptions and, judging by the questions and note-taking from my fellow classmates, a lot of other peoples’ too.

Myth #1: Water harvesting will save you money on water

Fact: Water harvesting will probably not make a significant financial difference. Since everything is measured by Starbucks these days, a typical residential harvesting system will save you enough for one to four more lattes per month. But more importantly than having extra coffee money, water harvesting saves freshwater for the future, reduces the strain on septic and treatment facilities, reduces energy and chemical use and adds to groundwater, among other worthwhile reasons. It’s not about cost savings, it’s about water savings.

Myth #2: A water harvesting system is expensive and difficult to install

Fact: Only if you want it gold-plated! Ok, actually a water harvesting system can be costly and painful (this one looks like a good example) but there are also simple, inexpensive methods that you can create yourself. Greg has several examples of both graywater and rainwater systems at his farm and his step-by-step directions were astoundingly simple. He also has a rainwater collection system that he claims is not worth the expense and trouble, so take the easy way out on this one.

Myth #3: A water harvesting system will be high-maintenance

Fact: The best type of system is passive, which means you install it and never have to touch it again. An active system with pumps and filters will require cleaning and upkeep, but why mess with all that when gravity and some mulch will do the same job? (This was the most fascinating part, to me. A small mulch bed holds a natural ecosystem that will purify your used soapy water so it’s perfectly harmless to your landscape, much like the bio-swales Kelly mentioned. How cool is that?) You may not be saving much money by harvesting but you won’t be spending any on maintenance, either. So let’s call it even, ok?

Myth #4: Rainwater harvesting is pointless in a dry climate

Fact: Sure we don’t get much rain, but you may be surprised how much you can collect and how useful it is. For every 1,000 square feet of collection area you can collect 600 gallons of rainwater per inch of rain. And don’t forget storm water runoff! And because freshwater is loaded with minerals by the time it reaches our faucets and hoses, irrigating with rainwater (which doesn’t have those minerals) balances the salinity of the soil. See? It’s not pointless after all!

If you’re already on board and want the specifics, I recommend getting very familiar with HarvestingRainwater.com. Don’t be fooled by the name, it covers harvesting graywater too. The site has everything from research, incentives, ordinances, materials and suppliers to instructional videos, demonstration sites and a harvesting calculator.

And if “become a hippie farmer” was one of your New Years’ resolutions for 2011 (I know it was mine!), then get to know Greg Peterson and his Urban Farm in Phoenix. The best inspiration for starting your own water harvesting system is seeing it in action and hearing first-hand how simple it can be. Greg’s #1 rule for living green is “no suffering allowed”; what could be better than saving water for the future and not having to suffer to do it?

Do you have additional concerns and fears that I didn’t cover? Or are you as excited as I am about the potential for recycling water? I’d love to hear, either way!