Learn About Rainwater Harvesting for Your Landscape

April 8, 2013

By Donna DiFrancesco, City of Mesa

Yes, it really is worth harvesting rainwater in the desert… really!

Have you ever noticed how plants appear greener and brighter after a good rain? It’s not just because the dust and dirt get washed off. Rainwater is a clean, salt-free source of water that contains many beneficial ingredients for plants. Rain can contain sulfur, potash, several other minerals and even microorganisms, all of which provide a boost to plant growth. During summer thundershowers there can even be an added bonus when lightening converts atmospheric nitrogen into a nitrogen solution for plants.

Because rainfall is so beneficial, as well as a precious resource, property owners should capture as much rainwater as possible before it runs off into the street. Historically, Native Americans and early settlers relied on harvested rainwater for drinking, landscape watering and agricultural uses. Today, even with a small property, rooftops and driveways make prime catchment areas. The rooftop of a 1500 square-foot home can collect almost 500 gallons from ½-inch of rain, making water harvesting well worth the effort.


Yikes! It’s not just about free water!

But water harvesting has another surprising benefit. Storm drains in our urban neighborhoods can collect all kinds of pollutants during a storm event. Microscopic particles of heavy metals like zinc and copper are commonly found. There’s also oil and petroleum-based hydrocarbons, fertilizers and pesticides that wash off lawns and landscapes, and even pet excrement contributes a significant amount of bacteria to urban streams and rivers. The more water we can collect onsite to be filtered by soil and plant roots, the better.

Cities are also realizing the great benefits of water harvesting for streets and roads and are looking more into collecting rain into right-of-way landscapes. Not only does it reduce the amount of water needed for the landscape, but it really has a positive impact on filtering stormwater before it reaches retention basins and parks where children and pets play or before the stormwater gets transported to environmentally sensitive waterways. If you want to see an impactful video on the topic, check out “How We Got Into Such a Mess With Stormwater.”

Tempe Workshop on Rainwater Harvesting sponsored by Water – Use It Wisely

While the low deserts of Arizona are currently approaching our dryer weather period (from mid-April through May), it won’t be long before summer monsoons have arrived. That’s why Water – Use It Wisely is sponsoring Ryan Wood from Watershed Management Group to speak on the subject! Here are the details:

Earth Care Conference: Going Native: Savoring the Southwest

April 20 from 9 a.m. to 4 p.m.

Community Christian Church, 1701 S. College Ave.

There are many programs taking place, including a keynote presentation by author Gay Paul Nabhan.  Here’s a synopsis of Ryan’s program. We hope you can attend!


Where does our water come from and what can you do to keep it flowing?
Join Ryan Wood as he explores our water resources and how you can keep the water flowing by implementing simple water harvesting strategies at your home. You will learn the basics of water harvesting, the different strategies for creating an integrated water harvesting system, and what you will need to know to install, use and maintain a residential water harvesting system.
Fifteen cities and water providers make up the Water – Use It Wisely regional partnership, many of whom offer water-wise workshops. Find this and many other partner programs at the Water – Use It Wisely calendar on our home page.