By Sharon Cohoon, Sunset senior garden writer

Tucson writer Brad Lancaster's appearance on National Public Radio earlier this month led me to order his book, Rainwater Harvesting for Drylands and Beyond. 

Frankly the first skim through was a little daunting. I got spooked by the charts.  And equations like "Estimated Net Runoff from an Impervious Catchment Surface Adjusted by its Runoff Coefficient."  On the second pass, though, I paid more attention to the illustrations, all of which are simple and clear and demonstrate there are dozens of things you can do to trap more water on your property without either being an engineer or hiring one. 

Lancaster's prose is as clear and straightforward as the book's illustrations.  And his passion and personal experience with his subject are apparent on every page. The list of the eight principles that guide his approach that opens his book are a good indication of both his writing and his philosophy:

Reprinted with the author's permission:

The Eight Principles of Successful Rainwater Harvesting.

1.  Begin with long and thoughtful observation.

Use all your senses to see where the water flows and how.  What is working, what is not?  Build on what works.

2.  Start at the top (highpoint) of your watershed and work your way down.

Water travels downhill, so collect water at your high points for more immediate infiltration and easy gravity-fed distribution.  Start at the top where there is less volume and velocity of water.

3.  Start small and simple.

Work at the human scale so you can build and repair everything.  Many small strategies are
far more effective than the one big one when you are trying to infiltrate water into the soil.

4.  Spread and infiltrate the flow of water.

Rather than having water erosively runoff the land's surface, encourage it to stick around, "walk" around, and infiltrate into the soil.  Slow it, spread it, sink it.

5.  Always plan an overflow route, and manage that overflow as a resource.   

Always have an overflow route for the water in times of extra heavy rains, and where possible, use that overflow as a resource.

6.  Maximize living and organic groundcover.

Create a living sponge so the harvested water is used to create more resources, while the soil's ability to infiltrate and hold water steadily improves.

7.  Maximize beneficial relationships and efficiency by "stacking functions." 

Get your water harvesting strategies to do more than hold water.  Berms can double as high and dry raised paths.  Plantings can be placed to cool buildings.  Vegetation can be selected to provide food.

8.  Continually reassess your system: the "feedback loop."   

Observe how your work affects the site — beginning again with the first principle.  Make any needed changes, using the principles to guide you.