[Sdpg] Bountiful Harvest There's Plenty Of Water In The Desert--For Those Who Know How To Grab It. By Kay Sather

Wesley Roe and Marjorie Lakin Erickson lakinroe at silcom.com
Sat Apr 10 23:58:22 PDT 2004


hi everyone
         I am posting a great water harvesting article Bountiful Harvest 
written in 1998 about Brad Lancaster Urban Permaculture Project and other 
Permaculture folks in Tucson Arizona, I would encourage folks to go to 
Brad's Website Rainwater Harvesting http://www.harvestingrainwater.com and 
pre-order his upcoming Book Rainwater for Drylands $20 plus $4 shipping  to 
be self published Fall 2004. Please support this grassroots way of raising 
money to pay for the publishing and support directly Permaculture Authors.
         The Santa Barbara Permaculture Network and South Coast 
Permaculture Guild will be organizing Brad Book Tour in Ca and Arizona in 
the Fall of 2004 and you will great a chance to hear a great inspiring 
Permaculture Speaker
                                 thanks wes

FROM WATER HARVESTING WEBPAGE
Rainwater Harvesting for Drylands is a toolbox of seventeen principles, 
numerous strategies, and countless tips that guide you in the sustainable 
harvest of rainwater. Well illustrated and clear, these tools can be used 
to make your built environment more beautiful, permeable, efficient, and 
productive, while reducing your cost of living. Within its 200 pages, 
you’ll find over 30 stories of people successfully welcoming rain into 
their life, landscape, and soil. And it invites you to do the same.

"Having seen Brad Lancaster's previous writings, and having marveled at his 
innovative design work, I cannot wait to get my hands on Rainwater 
Harvesting for Drylands. Pre-order yours now and help support this worthy 
project."

Toby Hemenway; Author of Gaia's Garden: A Guide to Home-Scale Permaculture 
and associate editor of the Permaculture Activist.

Brad is  self-publishing this book in the Fall of 2004. Your preorder is 
important to help offset printing costs on my end, and to save you money on 
your end! Please use the Order Form to reserve your copy at a reduced cover 
price.
http://www.harvestingrainwater.com/orderform.htm

ARTICLE ON RAIN HARVESTING

Bountiful Harvest  http://weeklywire.com/ww/08-24-98/tw_feat.html

There's Plenty Of Water In The Desert--For Those Who Know How To Grab It.

By Kay Sather

AUGUST 24, 1998:  IT WAS A situation that may have made the Tucson Water 
employee a bit nervous.

As he approached the meter, a tall, long-haired and bushy-bearded man 
appeared from an overgrown corner of the yard.

"What are you doing here?" the man asked. "You guys were here to read my 
meter just last week."

"We think it isn't working right," the city employee explained quickly. 
"I'm just here to test it."

The tall man broke into a grin, instantly dissolving any possibility that 
his unpruned appearance belonged to the kind of guy who might, say, mail 
out dangerous packages from a cabin in the woods. He was definitely more 
the friendly farmer type.

"So are you saying," he asked, "that my meter isn't measuring a normal 
water flow to my house?"

"Right."

"That's probably because with all the rain we've had lately, we haven't 
needed to use much."

He should have been able to say Well, duh. El Niño had just dumped so much 
rain on this city that every gringo in town learned to say at least two 
words of Spanish. But with all that free water, most Tucsonans continued to 
pay to have their water pumped up as usual from deep underground, not 
expecting it to make much of a dent in their water bill.

BRAD LANCASTER, THE homeowner in this story, is one of a growing number of 
desert dwellers who've begun to look at rainwater as a resource instead of 
a nuisance to be sent down to the streets. His water bill (for himself and 
his brother) actually read "0 gallons used" for two out of the previous 
four months. For each of the other two months, it read "748 gallons"--100 
cubic feet, the water company's smallest measured unit. In other words, it 
took two months for their water use to reach that minimum each time.

Sitting on his porch, surrounded by trees and gardens, Lancaster dismisses 
any belief that he's achieved some kind of miracle.

"It's mostly common sense," he says, citing the relevant figures off the 
top of his head: An average Tucson family of three uses 120,000 gallons of 
water a year, with about half of that going to outdoor use for landscaping, 
gardening, washing the car. Though rainfall can vary quite a bit from year 
to year, a quarter-acre lot will receive, on average, 67,000 gallons of 
water annually--more than enough to satisfy those exterior needs if the 
rainwater is kept on site. And it doesn't have to be complicated or 
expensive to do so.

"People think that to harvest water you have to have cisterns," he says, 
"but you don't. It's easier to store water in the soil. You can exceed your 
outdoor needs with nothing more than earthworks."

Perhaps the simplest example of Lancaster's "earthworks" is a vegetable 
plot on the north side of the house which receives rainwater directly from 
an unguttered roof surface. The garden has been dug low so that the slope 
carries the runoff down into it, away from the house. Shadecloth stretched 
overhead from the house to the garage-turned-workshop cuts down on 
evaporation from the area and shields people, too, from the harsh sun.

Both the house and the workshop are lower than the street, and rainstorms 
bring gutter flow onto the property through what used to be the driveway 
opening. Instead of seeing this as a potential flooding problem, Lancaster 
uses the water to his advantage. By placing a crescent-shaped mound of 
earth strategically across its path, he has constructed a swale--an area 
where water is slowed down to allow infiltration and plant uptake. Even in 
the desert, many trees and other perennials need nothing more than this 
occasional deep watering.

At another opening from the street, water is captured in a french drain--a 
gravel-filled trench that secretly holds water while allowing unsuspecting 
humans to walk safely (and dryly) on its surface. As inconspicuous as a 
french drain may be, it's remarkable to see one in action. One Green Valley 
resident dug a "french trench" across a slope where water from her 
neighbor's yard was flowing into her driveway. A fill of 3/4-inch gravel 
concealed her work, and now when it rains, the rivulet of water from next 
door seems to magically disappear into the earth. Of course, the water 
hasn't vanished. The thriving vegetation at the spot has obviously found it.

Water-harvesting techniques often yield this double benefit--solving a 
problem such as erosion while conserving a resource. Lancaster recently saw 
a chance to split the benefits with a next-door neighbor who came to him 
because his foundation was being "eaten away" by runaway storm water. In 
exchange for installing gutters to solve the problem, Lancaster got to 
divert the water onto his own property.

It's easy to safeguard against flooding, he says, by following a few basic 
principles. "Design your system to harvest water, but don't destroy any 
natural drainage. And always have an emergency overflow to the street." 
Swales should not be built to collect water near the house; he says a 
10-foot distance is safe.

DOESN'T ALL THIS water hoarding create prime real estate for mosquitoes?

Not with enough roots in the soil to draw in the water. And not with 
liberal use of the magic ingredient: mulch. By holding onto water, mulch 
prevents it from puddling or causing erosion while keeping it in the soil. 
The trees that shade his porch and yard are testimony to the effectiveness 
of mulching, Lancaster says.

"When we bought the house three years ago, all the trees were on the verge 
of dying," he says. Using "anything we could find that was free," including 
palm fronds, bark, straw, aged manure, and even rocks, Lancaster and his 
brother covered the soil around the trees, creating a layer of mulch a foot 
thick. "Then we watered everything really well. Once." With no additional 
water other than rainfall, the trees--planted in the '60s--not only 
recovered but doubled in size.

Laying down mulch starts a cycle that eventually takes care of itself. By 
retaining water it improves the soil, encouraging plant growth that 
contributes more mulch in the form of leaf drop or its own mass at the end 
of the season, further enriching the soil and increasing its ability to 
hold water. Planted areas, where water is needed, should be mulched and dug 
lower than walkways or other surfaces where water is unwanted. For 
Lancaster, every planted area is a sunken mulch basin--a water-harvesting 
system.

Unlike trees, vegetables and other garden annuals grown in the desert need 
water between rain events. So do people. This is where cisterns come in.

The largest of Lancaster's cisterns is a 1,200-gallon concrete tank he had 
built by a local septic tank company. It sits on a mound of earth near the 
house, higher than the rest of the property but lower than the roof that 
feeds it. Kids can climb onto it, but they can't fall in because the top is 
a concrete slab and the cistern has only three small openings: one where 
the downspout enters, one at the spigot, and one for overflow. The whole 
setup has no moving parts and requires no maintenance. Algae growth isn't a 
problem, since the cistern is closed off to light, and mosquitoes don't 
make it past the screen that covers the downspout opening. But the initial 
investment of $600 was considerable.

Lancaster says that more than one observer, on hearing this figure, has 
pointed out that the tank could be filled with groundwater for a few 
pennies. But for him and for others who capture rainwater, it's not 
primarily about saving money on water bills. It's about conserving Tucson's 
groundwater. It's about sustainability, water quality and realistic 
planning for the future. It's about saving our last remaining riparian 
areas, which (like the Santa Cruz River decades ago) are dying as the water 
table drops. And it can take the guilt out of desert gardening.

Besides, cisterns don't have to be expensive. To store runoff from his 
workshop roof, Lancaster built a cistern of several 55-gallon drums, 
connecting them with pipe so they function as one large tank. The drums 
come with 2-inch threaded holes that make the plumbing easy, and they're 
available from local bakeries for $3 to $5 each. The bricks and planks 
needed to support and elevate the system are easily salvaged.

Step-by-step instructions for building another inexpensive cistern are 
available from the Arizona Department of Water Resources. This 550-gallon 
cylindrical tank, designed by local builder Dan Dorsey, uses materials that 
can be salvaged or purchased at a hardware store for about $65--field 
fencing, plastic sheeting, and chipboard or old carpet. Dorsey uses this 
cistern himself, along with two others he built from wood and steel 
strapping (the kind used on shipping crates). Large volumes of water can 
exert tremendous pressure on the sides of a tank--7 1/2 to 8 1/2 pounds per 
gallon--so it's probably best not to experiment with your own design unless 
you have some idea of the physics involved.

Dorsey echoes Lancaster's message about earthworks. "All you really need is 
a $3 shovel," he says. His home sits down-slope from the alley behind him. 
Before he bought the property, water cut through the backyard via a ditch 
it had carved with erosive force. The Realtor was apologetic. As a result 
of the water "problem," Dorsey was able to negotiate a better price on the 
house. And now a series of swales, each emptying into the next when it 
fills, manage the flow and capture water for fruit trees, edible greens, 
amaranth, and other crops.

HOMEBUILDER AND WATER harvester Dave Taggett isn't especially interested in 
fruit trees or vegetables. But his passion for flowers is dramatically 
obvious to anyone passing by his yard.

He nourishes them with rainwater stored in a cistern made from a section of 
silvery, spiral-ribbed storm-sewer culvert. The culvert comes in three, 
four, and five-foot diameters, and really isn't that expensive--$15-$25 per 
foot plus cutting and delivery charges. He orders a 10- or 12-foot section, 
upends it into a bed of cement with the necessary plumbing, and runs the 
gutter downspout into the top. The column has a space-age elegance, and 
provides plenty of water pressure--"as much as you'd get from a faucet, 
maybe more," he says, opening the spigot full-force into a bucket to 
demonstrate.

Taggett has a strong sense of water ethics.

"I don't need a house this big," he says, glancing at his well-built, roomy 
home. "And I don't need all these little guys." He fingers an orange poppy 
with an affection that almost makes you question his statement. "I'm not 
going to take the water away from someone else."

For Taggett, Dorsey, Lancaster, and perhaps for water harvesters in 
general, living by a desert water ethic seems to be an adventure rather 
than a dreary or difficult moral obligation. Taggett tells the story of a 
young couple who pulled up to his curb one day in a yuppie-model car and 
called him over to talk. Taggett didn't remember the man, but the man knew 
Taggett.

"You got me into collecting my rainwater," the man said, "and I wanted to 
thank you."

"Yes, thanks," said the woman, rolling her eyes.

Taggett caught the gesture. "Let me guess. He's out in the rain at 3 a.m., 
checking the tank in his underwear."

"Exactly," the woman replied.

Taggett now builds rainwater storage systems (along with other 
earth-friendly, handicap-sensitive and energy-efficient amenities) into all 
of his homes. By choice, he no longer builds conventional houses. "It would 
be going backward, and I have no desire to do that."

THE DECISION TO collect the rainwater that falls on one's yard or rooftops 
may be a solitary one. But many properties, such as those of Lancaster and 
Dorsey, receive water from rain that has fallen elsewhere. What one 
does--or doesn't do--with rainwater inevitably affects someone else on the 
watershed.

Aren't water harvesters simply "stealing" water from their neighbors? 
Aren't they, ultimately, robbing the aquifer they're trying to protect?

Probably not significantly. Most of the water that falls on Tucson 
residences never reaches the underground reservoir they draw from. What 
doesn't immediately evaporate will flow into city streets, storm sewers, 
washes, and finally into the Rillito and Santa Cruz river beds. More than 
half of this flow infiltrates the streambeds, with about 90 percent of the 
infiltrated water eventually reaching the aquifer. But much of the 
infiltration occurs north of Tucson, contributing nothing to our central 
well field, where the water deficit is growing most rapidly.

Home-harvesting would have no effect on the volume of mountainfront 
seepage, a very important form of natural recharge for the Tucson Basin. 
And, unfortunately, some of the water in our aquifer will never be 
naturally replenished--ancient layers that lie under impermeable rock, for 
example, or vast areas of soaked clay that will collapse (subside) and lose 
permeability once drained.

And those neighbors may actually benefit from upslope harvesting. What's 
left in the ground after the water harvester's gardens have had their fill 
will continue to travel subsurface, protected from evaporation.

That's important, since evaporation rates for desert climates are high. In 
the Sonoran Desert, where 8 to 16 inches of rain may fall in a year, the 
evaporation rate may be 100 or more inches per year. One UA study of the 
area surrounding the San Pedro River concluded that a full 95 percent of 
the rain that falls there evaporates. Getting rainwater into the soil or 
into a closed tank as soon as possible after it falls is clearly the most 
efficient, least wasteful way to obtain water in the desert. When this 
rainwater is used instead of groundwater, it's making a very real 
contribution to the water supply. Everyone benefits.

PRESENTLY, WITH GROUNDWATER still supplying the city's needs, few Tucsonans 
are worried about losing rainwater to their upslope neighbors. Most 
developers, engineers and architects are more concerned with avoiding 
flooding than with the benefits of keeping water on site.

Barbara Rose would like to see this change. Rose lives on 20 acres in the 
Tucson Mountains and receives runoff from about 30 acres of watershed on 
the east side of the ridge above her home.

"I get about 15 million gallons of water a year moving across my land," she 
says. "I currently harvest 900,000 on the acre around the house." Rose uses 
techniques already mentioned: swales, french drains, basins, and cisterns. 
Her several tanks include a rammed-earth cistern that she designed and 
built with local rammed-earth specialist Quentin Branch. She also uses 
gabions--cages of rock--as porous mini-dams to slow the flow of her natural 
drainages and to check erosion of the hillside.

But when looking at the plans for a new development across the road, Rose 
realized it was the water she (and her neighbors) did not harvest that 
would affect the project's design--and ultimately the neighborhood. The 
engineers, using the conventional approach to flood control, had designed a 
cement-walled channel to contain the runoff from her watershed and direct 
it past the development. Harvesting techniques used higher on the watershed 
could eliminate the need for the channel, leaving that strip of desert 
undisturbed to serve as a buffer zone.

Rose has seen a growing interest in water harvesting on the part of 
professional engineers, architects and planners. "Planning developments 
that benefit from rainwater use on site can reduce the costs of typical 
grading and channeling, as well as add to the real value of the development 
for future residents," she says.

With funding provided by PRO Neighborhoods, Pima County, and the Town of 
Marana, Rose is organizing a series of workshops that will include training 
in water harvesting for the professionals involved in shaping the imminent 
development of her area, as well as for homeowners. She hopes the classes 
will foster an understanding that existing washes, and the desert 
vegetation associated with them, are at the heart of sustainability for the 
Tucson Basin, and should be preserved as functional.

IN A DESERT, SAYS Brad Lancaster, "there should be no such thing as a 
flood. The Flood of '83 should have been the Bountiful Harvest of '83."

He believes city streets should drain into tree wells instead of the storm 
sewer. A study in Davis, California, showed that the planting of roadside 
trees in one neighborhood reduced the ambient temperature by an astounding 
10 degrees. Such studies suggest that downtown Tucson might still avoid 
becoming a "heat island" if simple water harvesting for vegetation and 
trees was used consistently. Dissolved pollutants from asphalt and cars may 
not be safe to feed to an edible garden, but native trees and even fruit 
trees can handle them just fine, Lancaster says.

Unless it picks up surface pollutants, rainwater is in a class by itself 
when it comes to what we call "quality." Not only is it missing the 
high--and rising--concentration of salts found in groundwater, it also 
contains nitrogen created by lightning. Anyone who's observed the joyous 
green response of a garden to a good rain, as compared to the results of 
even a generous dousing with groundwater, knows that from a plant's 
perspective the difference in composition is real. Evaporative coolers can 
also benefit. When his gardens permit, Taggett runs rainwater through his 
cooler for awhile, flushing out the salts and postponing maintenance.

Rainwater is actually better for people, too. According to the UA 
Department of Atmospheric Sciences, it's 100 to 1,000 times purer than our 
groundwater. Though roof surfaces of asphalt or lead paint can contaminate 
it, metal, slate, mission tile, and even reflective-paint-coated surfaces 
(if recoated yearly) are safe for collecting drinking water. And a few 
weeks of cistern storage can actually improve the water. Microorganisms 
associated with the organic matter at the bottom of the tank work to purify 
it. To avoid disturbing this settled organic material, cisterns should be 
designed with the spigot an inch or two above the floor.

Rainwater is the only source of drinking water in many parts of the world, 
including some areas of Mount Lemmon. Anyone who has doubts about the 
safety of rainwater can have it tested, for a fee. (Analytical laboratories 
are listed in the Yellow Pages.)

It might be tempting to take a look at the Central Arizona Project from a 
water harvester's point of view, and ask whether we could have done without 
it. But the taxpayer dollars have already been spent, the acres of desert 
paved. However, consumers who object to the prospect of CAP on tap might be 
comforted to know they have an alternate source for drinking water. More 
importantly, anyone who owns a surface that rain falls on has the power to 
reduce, if not eliminate, their dependence on the city water supply--not a 
bad idea, given the uncertainty of Tucson's water future.

Our summer monsoon season is drawing to a close. Probably, most of the 
rainwater that fell on your roof and yard escaped to the street, turning it 
into an undriveable river while leaving your landscape high and almost dry. 
But the winter rains are only a few months away. You should have enough 
time to install those gutters and hook up your cistern of choice. Or just 
grab a shovel and start moving dirt around. It might be the most radical 
political act you'll ever commit.
Santa Barbara Permaculture Network
(805) 962-2571
sbpcnet at silcom.com
www.sbpermaculture.org

"We are like trees, we must create new leaves, in new directions, in order 
to grow." - Anonymous





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