Rainwater Harvesting:An Interview with Author Brad Lancaster  
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Did you know that less than half of one percent of the water on Earth is available for human use? The balance is either in the oceans or is frozen.

Today, with many parts of the world experiencing drought and lack of water due to climate change, it is of utmost importance for humankind to conserve water.

HOST:
On this edition of Planet Earth: Our Loving Home, Brad Lancaster of Tucson, Arizona, USA will explain how we can best preserve rainwater for times of drought or when existing surface water evaporation is accelerated by rising temperatures.

Mr. Lancaster specializes in permaculture, or creating sustainable environments that mimic the structure and interrelationships found in natural ecologies. He has published two best-selling, award-winning books on storing rain entitled Rainwater Harvesting for Drylands and Beyond, Volumes 1 and 2.

These guides demonstrate how to maximize water collection at home, in the surrounding landscape and in neighborhoods.  

Let’s now hear from Mr. Lancaster on how we can all do our part to keep fresh water abundant wherever we live.

Supreme Master TV (f):
So, what exactly is rainwater harvesting?

BL (m):
Basically the idea is to capture the rain as close as possible to where it falls so that we can beneficially use it for irrigation, drinking, bathing, whatever makes the most sense for the site.

BL (m):
It can be done in a number of different ways. Most commonly people think of capturing the water that’s coming off the roof into a tank or a cistern.

And that works great if you want to drink the water, if you want to wash with it or irrigate a garden.

But I think the cheapest and easiest way to harvest the rainwater is to create water harvesting earthworks or bowl-like shapes in the landscape that capture the rain, and infiltrate it into the soil.

You mulch the surface, so water quickly infiltrates. And then you plant vegetation that will be
the living pump and access the water. So then you access that water in the form of fruit, shade for cooling, windbreaks, erosion control, beauty and so on.  

And the great thing about that system is, it’s no more than the cost of a shovel.

HOST:
Mr. Lancaster’s interest in rain harvesting sparked when he noticed the depletion of water resources in his own environment in Arizona.

BL(m):
Our groundwater tables were dropping, our rivers were drying up and we were losing our springs. Why can’t we live in a way that makes things better?

So I started to seek out things that would make a positive difference, and that’s when I came
across water harvesting.

And I visited a number of people and cultures that were doing this and saw the potential, saw how they turned things around for the better and I thought, “I want to do this too.”

HOST:
In the African country of Zimbabwe was where Mr. Lancaster learned the valuable lessons about storing rainwater.

BL(m): I visited Mr. Zephaniah Phiri Maseko. And he is a subsistence farmer in the driest region of Zimbabwe, Zvishavane. They get about 22 inches (56 cm) of rain a year.

But they’ve been in drought so they’ve been lucky to receive ten inches of rain a year. (Okay.)

Andm he showed me how he had turned an eroding wasteland of a farm into a relative oasis. And he did this by “planting the rain” everywhere he could, starting from the top of his watershed and working all the way down to the bottom, with just simple structures like low rock walls across the slope, to slow the flow of the water, to make depressions when he had soil, to make contour berms, just a berm of earth across the slope and plantings on contour and so on.

So he would infiltrate the water into the soil and by doing so through the year he put more water into the soil than he took out from his hand-dug well.

And since he was putting more water in than he took out each year the water table rose.

HOST:
Zimbabwe is not the only country where Mr. Lancaster witnessed the life-saving effects of rainwater harvesting.  

He had also traveled to India and saw firsthand how a community saved their environment and natural resources through these simple water conservation methods.

BL(m):
It was in the Alwar district of Rajasthan.

(Okay.)

And all these villages came together to reforest their watersheds, to create water harvesting earthworks, plant the rain, and they did this on a large enough scale that they slowed the water loss of runoff, they increased infiltration and they actually brought back five rivers that they had killed from their over-extraction of water and deforestation of the watersheds.

And they brought back year round flow. And the village, then as a whole, they solved their problem. They de-silted the reservoirs so they could capture the water again and bring the well levels back up.

HOST:
When Planet Earth: Our Loving Home returns, Brad Lancaster will explain how we can keep
the water supplies in our towns and cities plentiful.  

You are watching Supreme Master Television.

HOST:
This is Planet Earth: Our Loving Home. Today we are speaking with Brad Lancaster of Arizona, USA, the author of two award-winning books about rainwater harvesting.  

Next, Mr. Lancaster explains how it is beneficial to allow precipitation to penetrate the soil and later be drawn up by plants, which he calls the “living pumps” of the Earth.


If you store the water under the soil you lose less to evaporation, and it’s less erosive. It travels more slowly. It becomes productive, not destructive.

It’s the living pump that draws the water up through its roots to then produce the fruit, the windbreaks, the erosion control and so on.

HOST:
According to Mr. Lancaster, the key to saving as much water as possible is to slow down the flow of water through the soil.

BL(m):
Because the slower it’s traveling, the more opportunity there is for life to access it and grow more resources and to filter it. And that’s what water wants to do.

In healthy rivers and streams it meanders, it never goes straight. And by meandering, it’s slowing itself down. It’s a healthier system. And the great thing is by doing this the water leaves your property at a higher quality than it entered the property.

Supreme Master TV (f):
How does that work?

BL (m):
It’s because when you have runoff coming across your property, it’s picking up sediments and maybe some contaminants from the soil float over. And then you’ve got these living filters of vegetation and mulch and soil life that clean the water.

So instead of it washing across and leaving your property as muddy brown water, it instead leaves as clear water, either on the surface or maybe below the surface.

HOST:
Even on slopes where rainwater runs downhill quickly, measures can be taken to allow more of the rainfall to percolate into the ground.

BL(m):
If the slope’s coming down this way, you create an open-armed hug of berms, earthen berms. So the water’s coming down to you and it’s almost like you want to embrace it, okay? (Oh) So the water collects in the berm, and then once it’s full it overflows from one to the next below.

HOST:
One of the easy and effective things to do is direct run off rainwater from the streets to water harvesting basins to water trees.

The run off from the street freely flows to the basins to irrigate the trees, and trees then grow to shade over the street.

So it becomes this wonderful sustainable system where the street is the water source of the trees that shade and cool the street, because throughout the world, the more we pave of the land, the more summer temperatures increase because the asphalt of streets absorbs the heat during the day and it absorbs the sun’s direct rays, stores that heat in the mass of the street and then it radiates it out at night.

HOST:
Mr. Lancaster’s own home, which is located in a desert region, is a testament to the amazing amount of rainwater that can be collected in a year.

BL(m):
We harvest over 100,000 gallons (380,000 liters) water a year on our 1/8-of-an-acre (505 square meters) site and most of that is harvested in the soil, but we also have a 1,200 gallon (4500 liters) rainwater tank.

So we harvest it in a number of different ways. And then the water stored in the tank, we use it to irrigate our garden.

HOST:
Mr. Lancaster is also involved in other community activities to help keep the neighborhood alive and vibrant.

BL(m):
So since 1996, we’ve planted over 1100 trees in the neighbor. And not just us, we get all our neighbors to do it, it’s a community effort. But before we plant the trees, we always plant the water.

Supreme Master TV(F):
So can you explain what that means?

BL(m):
So what you would see, in and around the trees are these sunken water harvesting earthworks.

Supreme Master TV(F):
Right.

BL(m):
So we’re creating land forms that will capture the rain, we mulch the surface and plant it so it quickly infiltrates. That way we don’t have puddles on the ground.

BL(m):
Because if you have puddles you could have mosquitoes. (Oh Right.) We store it beneath the surface so there is no mosquitoes problem.

HOST:
With modern day conveniences, society has abandoned its traditional practice of safeguarding water.

BL(m):
We’ve had this hundred year period where we have forgotten about the systems we used to use, because within this past hundred years piped-in water has been introduced.

So, we’ve lost the feedback loop. We just turn on the facet and water comes out. But where does it come from? We’ve lost that connection, whereas before we knew we got the water from this spring or this creek or this hand-dug well.

We were more connected with where the water came from. So there was more of an incentive to use strategies that would enhance these local water resources, because we saw when the well levels dropped, we saw when the creek flow lessened.

Now that these large-scale municipal systems are starting to go dry, I think we need to start to look back at these older systems that helped us out. We can use more recent knowledge to enhance them.

HOST:
We convey our sincere appreciation to Brad Lancaster for sharing his expertise on how to collect rainwater. May your noble work to protect our Earth’s precious resources be evermore fruitful.

Fro more information about Brad Lancaster and his book Rainwater Harvesting for Drylands and Beyond, please visit harvestingrainwater.com