Water in the landscape

Every year, far more water falls on your land than you'll ever use. Most of it runs off, carrying soil with it. This lesson is about keeping that water on your land: slowing it down, spreading it out and letting it sink into the ground, where it feeds plants and refills the water below.

The tools are simple and old: shallow ditches, low mounds, basins, ponds and mulch. Placed well, they can turn a dry, eroding slope into a green, productive one within a few seasons.

An inch of rain on one acre is about 27,000 gallons. That number surprises nearly everyone, and it's the reason water harvesting matters even in dry places.

You'll never catch all of it, and you shouldn't: streams and neighbors downhill need water too. But catching even a small share in the soil, right where your trees and gardens grow, makes a remarkable difference.

Brad Lancaster, who turned a dry lot in Tucson into a green oasis using only rainwater, sums up the approach in eight principles. They work in any climate.

1. Begin with long and thoughtful observation. Watch where water goes in a real storm (Lesson 1).
2. Start at the top and work down. Catch water high on the land, where there's less of it and it's easier to manage.
3. Start small and simple. Many small catchments beat one big, risky project.
4. Slow, spread and sink the flow. The heart of it all.
5. Always plan an overflow. Every basin and swale needs a safe path for big storms, and that overflow can water the next feature down.
6. Maximize living and organic groundcover. Plants and mulch soak up water and keep it from evaporating.
7. Stack functions. A basin under a fruit tree waters the tree; the tree shades the basin.
8. Keep watching and adjusting. Check your earthworks after every big storm.

Start with the smallest tool that does the job. Most homesteads need far more mulch basins and rain gardens than ponds.

Building a swale well

1. Find the contour with the A-frame level from Lesson 1, and stake it.
2. Dig the ditch level, not sloped, and pile the soil on the downhill side.
3. Build a spillway at one end, armored with rock so overflow can't cut a gully.
4. Plant the berm right away with trees, shrubs and groundcover, and mulch the ditch.

Hard surfaces shed nearly every drop. A rain garden turns that runoff into a flower bed. Run the downspout or a shallow channel into a level basin, planted with tough plants that tolerate both wet spells and dry ones.

A pond brings life to a homestead: water for animals and orchards, a home for frogs and birds, a reserve for fighting fire, and a beautiful place to sit. It's also the earthwork that most needs care and planning.

Rules to check first

Never dig in or dam a stream or creek without permits. Those waters are shared, and the rules protect neighbors and fish downstream.

Water harvesting changes how you see a storm. Instead of watching water rush away down the road, you start to see it filling basins, soaking under trees and quietly refilling the ground below. Year by year, the land holds more, and stays green longer into summer.

Next, we put soil and water to work in the place that feeds the family every day: the kitchen garden.

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