Uncategorized Archive


Palm Oasis and Red Bread at Al Absaa, Saudi Arabia

Thursday, July 29th, 2010

by Brad Lancaster, www.HarvestingRainwater.com, © 2010

Number 3 in a series of Drops in a Bucket blog entries on Brad Lancaster’s and David Eisenberg’s U.S. State Department-sponsored adventures and gleanings in the Middle East

Al Absaa, Saudi Arabia, April 2009

At Al Absaa we toured irrigation projects within the largest oasis in Saudi Arabia. Over one million date palms grow here. But the springs that have fed the oasis for generations are going dry. Oil drilling by Aramco has diverted, blocked, or consumed water flows that used to feed the oasis. The city of 1.5 million is also rapidly growing and consuming additional water. This is a story I encounter again and again the world over; this time it just happens to be in Saudi Arabia.

[...]

One spring, “The Mother of Seven (Streams),” is now the mother of none. Twenty years ago it stopped flowing on its own. Water must now be pumped. We looked down into the deep hole from which the spring water used to flow. The hole was dripping, but empty.

Speaking to the father and son. Photo by David Eisenberg.A father and son were swimming in a pool fed by the spring’s pumps. The father told me that the water used to be warmer, that he always swam here as a boy, and was glad his son could do likewise. I wondered if there would be water here for his grandson to swim in.

For the rest of the blog post and photos, follow this link to Brad's blog on his website.

Cisterns of Old Jeddah, Saudi Arabia

Monday, July 19th, 2010

or, If You Pray for Rain - Harvest It

By Brad Lancaster, www.HarvestingRainwater.com, ©2010

Number 2 in a series of Drops in a Bucket blog entries on Brad Lancaster’s and David Eisenberg’s U.S. State Department-sponsored adventures and gleanings in the Middle East

Jeddah, Saudi Arabia, April 2009

Most of the water people now drink in Saudi Arabia is desalinated seawater. And there are great costs, among them air pollution from the power plants which burn oil to run the desalination plants. We read articles daily on the many people falling ill from the pollution.

The new Saudi Arabia is very dependent on this oil, not only for water, but the mechanical heating and cooling of the new modern buildings of imported concrete, steel, and glass.
New stand-alone modern high-rise and its conceptual “courtyard” (vertical space in the glass wall) referencing the functional traditional courtyards where people gathered in a passively protected microclimate

But the traditional dynamic Saudi culture was borne from surviving and thriving in this hot, dry climate — without oil, imported building materials, and appliances. We wanted to see the old practices of harvesting water, building with local materials, and passive cooling and heating. So, we headed for old Jeddah.
Traditional old-Jeddah courtyard created by the shelter of clustered buildings

Old Jeddah, Saudi Arabia, is a gem, and as our guide Sami promised, it is replete with a rich tradition of harvesting rainwater, life, and vernacular architecture. Sami Nawwar was our lively host. He is caretaker of the grand Nasseif House/Al Balad at the core of old Jeddah. Sami is hugely excited about old Jeddah and has been fighting to save it for over 40 years.

To join Brad, David, and Sami on the rest of their tour of old Jeddah, click here.

Watergy

Thursday, May 13th, 2010

By Brad Lancaster

© 2010 www.HarvestingRainwater.com

Watergy is a term coined to describe the interconnection of water and energy. Every time we consume power we consume water. This is because water is used in the generation of our power – in Arizona this figure ranges from 0.001 to 56 gallons of water per kWh of power consumed.1 Therefore, anything we can do to reduce our power consumption also reduces our water consumption.

Typically the amount of water consumed during power generation is much greater when the power is generated at centralized power plants, as opposed to on-site with renewable power production such as rooftop solar, whose water consumption is negligible.

Introducing a Watergy Cost Calculator for You and Your Community

How much water is expended in the generation of electricity from different sources?

How much energy, and subsequently embedded water, do average U.S. and Arizona households use per month, depending on where their energy comes from?

How about you and your community?

Use this one-page Community Watergy Calculator (PDF version – non-interactive) or Community Watergy Calculator (Excel version – interactive) to find out.

Click the image for a larger size.

The Watergy Cost Calculator. Notice how a Tucson, Arizona, household consumes 558 gallons of water per month via its electricity consumption if it gets its power from coal (the primary source of electricity in Tucson), but consumes only 1 gallon of water per month via its electricity consumption if it gets its power from rooftop solar. Now let’s go up in scale. Notice how all Tucson households combined consume 112,161,890 gallons of water per month via their combined electrical consumption if they get their power from coal, but they would consume only 219,925 gallons of water per month via their combined electrical consumption if they were to get their power from rooftop solar. In the Excel version of the spreadsheet, you can enter the number of households in your community to generate ballpark numbers for how much water your community consumes through its power generation.

The Community Watergy Calculator was conceived of by me, and created by Megan Hartman, based mainly on watergy data for Arizona from this wonderful and succinct resource “The Water Costs of Electricity in Arizona.”

Still more watergy information can be found at www.harvestingrainwater.com/watergy-climate.

Before I speak or teach in various communities, Megan generates one-page Water Conservation and Climate Data sheets for those communities. Many of these are available here, with more being added on a regular basis. These spreadsheets also list:

• What percentage of the community’s energy consumption is used to move (or move and treat water), depending on the data we are able to obtain.

• How much rain per person per day falls on the community in a typical year (rainfall GPCD) compared to how many gallons of municipal water per person per day are consumed in a typical year (municipal GPCD). In most cases, per year, a greater volume of rain falls on the community than is provided by the municipality. This helps make the case that if the community were to harvest and utilize more of that free, high-quality rainwater, it could reduce or eliminate its depletion of local water sources, and reduce or eliminate the “need” for the high cost/high energy importation of water from elsewhere.

Click the image for a larger size.

Water and Climate Data Sheet for Tucson, AZ. Notice how the average Tucsonan uses 112 gallons of municipal water per day. And notice how during an average year there are 198 gallons of rain available per person per day – if only we were to harvest that rain and make it available throughout the year. To arrive at this rainfall GPCD figure, the spreadsheet calculates how much rain falls on the surface area of Tucson in a year of average rainfall, then divides that figure by 365 (days per year), and then divides the result by the population of Tucson. Also notice that 44% of the City of Tucson’s annual municipal energy consumption is used to move and treat water.

For simple and effective tips on how you can greatly reduce your energy consumption at home; increase your on-site passive heating, cooling, and solar power production; and enhance comfort and productivity, see Chapter 4 of Rainwater Harvesting for Drylands and Beyond, Volume 1. The whole book is packed with great info on how you can make progress on goals like these, while greatly enhancing the potential and use of your local rainfall, stormwater, greywater, and more.

[BREAK]

1. Extrapolated from Water Costs of Electricity in Arizona, a Project Fact Sheet of the Arizona Water Institute (Tucson, Arizona) from a 2007 investigation by Pasqualetti & Kelley. Fact Sheet ID: AWI-07-102 Pasqualetti.

Rain Beer

Friday, April 9th, 2010

By Brad Lancaster

© 2010 www.HarvestingRainwater.com

Rainwater is known as “sweet water” throughout much of the world due to its pure “sweet” flavor when compared to brackish, alkaline, chemically-treated, or polluted ground and surface waters. Now it is also known as “beer water.” And folks, it is good – very good.

I sampled numerous pints of Golden Number Ale, a deliciously smooth beer made with rainwater harvested off the roof of the 5 Seasons Brewery in Atlanta, Georgia, while in town to attend the American Rainwater Catchment Systems Association (ARCSA) conference of 2009.

Rain beer
Great folks enjoying great rain beer
Drinking rain beer with wonderful Rain Harvest Systems personnel

This rain beer was a first for the brewery, and a huge success. First off, water tests found the quality of the harvested water:

easily passed all EPA requirements, and

exceeded that of Atlanta’s municipal water (link).

The soft quality of rainwater is also superior for brewing, according to 5 Seasons’ master brewer, Crawford Moran, since it contains a fraction of the dissolved minerals of harder city water. Moreover, it is excellent drinking water. I found the taste of Atlanta’s tap water disgusting, but chugged down the sweet rainwater. And soon you may be able to as well, since 5 Seasons is looking into using rainwater for all its restaurant’s table water.

Secondly, the brew resulted in a flood of glowing media attention, including coverage by CNN, and a greater public awareness of the potential of rainwater collection.

Yet 5 Season’s harvesting practices go well beyond the beer.

It reuses the waste vegetable oil from the kitchen both to boil the blend of ingredients called “wort“ used to make beer, as well as to power its fleet of greasel-fueled catering vehicles.

Collecting used cooking oil from the kitchen above in the white tank within the basement below
5 Seasons catering truck fueled by biodiesel made from used fryer oil

Some of the spent grain from the brewing process is then used to make bread served in the brewery’s restaurant. A local farmer takes the rest, composts it, and then returns the nutrients by providing the restaurant with locally grown organic produce. (Many friends and I have found the spent mash also makes a great free source of feed for chickens and goats).

Collecting the used mash from the brewing process. Used cooking oil fuels the burners cooking the batches of beer.
Chowing down on tasty spent-beer-mash bread

These practices connect/reconnect the brewery and its clientele with some of their local life cycles, resource bases, and community, while also enhancing resiliency in times of dwindling water. Atlanta gets much of its water by pumping in over-allocated Chatahoochee River water. Court battles with other communities using that water threaten to cut Atlanta off from its current take. But as long as it rains, there will be rain beer because it is made with 100% gravity-delivered rainwater collected and filtered on site.

Considering that Atlanta’s annual rainfall averages 50 inches (1,270 mm), that 5 Season’s water tank capacity is 850 gallons, and that the roof area draining to the tank is about 1,800 square feet (167 m2), brewmaster Moran figures that 5 Season’s set-up provides enough water to brew a batch of beer with every 30 minutes of rain (each batch requiring 650 gallons (2,460 liters) of rainwater.

5 Seasons' rainwater cistern below roof catchment
Roof area draining to cistern

This is a boon in both dry and wet years. In dry years the rain beer production does not strain local water supplies. And in both wet and dry years the rain collection reduces the flooding threat for downstream areas of the community during storms by slowing, spreading, and sinking the water flow higher in the watershed through local beer.

This ratchets the brewery’s efforts in the slow food movement even higher into the realm of the growing slow water movement, both of which are renowned for delicious delights that celebrate and enhance local resources in a way that is a bun dancing fun!

Sipping delicious sweet water — harvested rain
Chugging down that delicious rainwater!

Details:

RainHarvest, a nearby locally owned business, provided 5 Seasons Brewery with all the equipment needed to harvest the rain, including 6 stages of filtration followed by dual-beam ultraviolet sterilization. The primary system components include:

• Leaf Eater preliminary leaf and debris filter

4" First Flush Diverter

• Graf Optimx Pro filter

• Rainwater collection tank (existing tank is being upgraded to larger size)

• Graf 1" floating extraction filter

• Goulds 1/2 Horsepower Pump

• SmartPress Pump Controller

• Two Full Flow 20" Filter Units ((1) 5 micron particle filter and (1) 1 micron absolute carbon block)

• UV Pure Dual-beam UV Sterilizer

For more info on this system, water tests, and RainHarvest see:

www.RainHarvest.com/info/beer

Pre-tank filtration

Post-tank filtration (micron filter, carbon filter, UV light)

Update: April 2010
Two months after my visit to the 5 Seasons Brewery, the Fulton County Health Department shut down the production of rain beer. According to Russ Jackson of RainHarvest Systems, the Health Department had no legal ability to do so, and thus it (who?) pushed the case up the chain to the Georgia Environmental Protection Division (GEPD).  The GEPD then claimed that the rainwater harvesting system was a public water system, so 5 Seasons would need a permit to operate a public water system. But there is no infrastructure within the GEPD to address rainwater as a source for a public water system. Rather than adopt the necessary codes/guidelines /etc., the GEPD has said that this matter is out of their jurisdiction. So for right now, 5 Seasons is unable to operate their rain brew system, since the bureaucracy has not expanded its box to incorporate the out-of-the-box rainwater-harvesting – despite the fact that the harvested and filtered rainwater quality exceeds the municipal water system’s water quality.

But 5 Seasons Brewery and RainHarvest Systems are not giving up. Stay tuned for the next development.

Green Burials

Sunday, March 14th, 2010

By Brad Lancaster

© 2010 Drops in a Bucket Blog, www.HarvestingRainwater.com

When I was little I was terrified of death. I often cried myself to sleep as I thought of the end of life. It seemed so bleak, pointless, and severe.

Mom tried to comfort me with the concept of going to heaven. This did not reassure me at all. “How do you know there is a heaven?” I’d ask. “Have you been there?”

Eventually, I just numbed myself to the fear by burying it in the recesses of my mind and body.

Years later the fear evaporated with an incredible discovery – composting. Yes! Here was tangible proof that there was life after death, that everything did not just end/stop/vanish with death. Instead, things transformed. In the compost pile I saw kitchen scraps, weeds, and a dead chicken decompose into beautiful, rich, fertile soil in which earthworms, mycelia, chiles, and all kinds of new life grew.

Death no longer scared me, now it excited me. My composting dead body could generate myriad life! Don’t get me wrong: I’m in no rush to experience this. But when it eventually does happen – no problem.

Maybe.

My dead body could generate life, or more death depending on how it is disposed of.

The conventional death industry embalms bodies with a toxic brew of formaldehyde, phenol, and menthol, which can contaminate groundwater and generate cancer and other disease in those doing the embalming.1 According to Grave Matters, today the U.S. funeral industry buries over 3 pounds of the formaldehyde-based “formalin” with every embalmed body (totaling 800,000 gallons [3,028,000 liters] of formaldehyde a year),2 while from the Civil War era to 1910, arsenic, zinc, and lead where the preferred toxic embalming compounds.3

Then there are the caskets, turning cemeteries into landfills. Grave Matters states, “Over time the typical ten-acre [4 ha] swath of cemetery ground contains enough coffin wood to construct more than forty houses, nine hundred-plus tons [816,000 kg] of casket steel, and another twenty thousand tons [18,143,000 kg] of vault concrete.”4

A conventional cemetery

Cremation avoids embalming toxins, and the body can be burned in a shroud or cardboard container instead of a standard casket to consume less fuel and release fewer pollutants. But the fuel needed to incinerate the body is still substantial. Carbon monoxide and sulfur dioxide are typical emissions along with toxic trace metals such as mercury – which comes from dental fillings (another good reason to ask for mercury-free fillings while alive).

All crematories in the U.S. may emit 5,000 pounds [2,267 kg] of mercury a year, while in the United Kingdom four times that amount is emitted due to a higher percent of the population choosing cremation.5

Depressing.

Deadening.

Friend and mentor Tim Murphy gave me a different vision. He wants to be buried toxin-free and naked, ass up, in the fetal position, with an acorn up his butt. “Plant me, and plant a tree. Years later you and others can come sit under my shade, harvest some acorns, and celebrate what is possible.”

I sometimes think of Tim as a radical traditionalist, and a small, but growing segment of the death industry is enabling others to take a similar path that encourages the natural decomposition of the dead and regeneration of other life from the process rather than trying to halt or slow what will eventually happen anyway. The website www.GreenBurialCouncil.org is one conduit to this path. And the book Caring for the Dead: A Complete Guide for Those Making Funeral Arrangements with or without a Funeral Director by Lisa Carlson is another conduit if you want to reduce or eliminate your participation in a death industry.

A green burial does not allow toxic embalming, concrete vaults, or elaborate caskets, which can reduce the cost of a burial by $8,000 to $12,000, according to memorial ecologist Joe Whittaker. Young trees or an engraved field stone are recommended over tombstones.

I experienced a new green or conservation burial ground for all faiths first hand at Honey Creek Woodlands just outside of Atlanta, Georgia. It is a beautiful place with very caring and dedicated staff, including Joe Whittaker. And it is erupting with new life.

It is located on and beside a section of once-grazed and clear-cut forest in the heart of the 2,100-acre [849-ha] grounds of the Monastery of the Holy Spirit. The monastery grounds are bordered by and connected to a state park and the network of footpaths, creeks, and wildlife corridors of the park and encompassing 8,000-acre [2,327-ha] Arabia Mountain Heritage Area. This is a huge strength for a final resting place, since many people already feel connected to this land.

Site of old clearcut at Honey Creek Woodlands
Old clearcut site being regenerated with new growth and green burials

First and foremost, the burial grounds are a nature preserve, with the goal of enhancing a 50-year succession back to a mixed hardwood forest, through such practices as selective weeding of invasive exotics, seeding and planting native plant stock, and adding organic matter to the soil.

Bodies are planted just 3 to 3.5 feet [0.9 to 1.06 m] deep because microbial activity and soil life drops tremendously at depths greater than 4 feet [1.21 m]. Above the body the excavated soil is placed in a mound with the topsoil placed back on top for a total initial “depth” of about 5 feet [1.5 m]. This is then covered with a light pine needle mulch and native wildflower seed. The Georgia Native Plant Society ensures only natives are used. Flowers and butterflies soon cover the 2-foot [0.6-m] tall burial mound – over 64 species of butterflies were counted in one day in 2008. The mound settles completely after a few years.

Day-old green burial
Older, settled burial mound

The process is so visible! So beautiful! I visited a day-old burial; fresh flowers still atop the grave. Ten feet [3 m] away, dried and shriveled flowers rested atop a week-old burial. And as I looked about I saw I was surrounded by burials, all in various stages of settling and regeneration. The older they were, the greater the density of vegetation atop them, and the more level the soil.

I saw a family cremation plot circle of field stones surrounding a tree. All were again reunited and rooted around their family’s tree.

I felt revived just being in this regenerating forest. I felt…

Alive!

Death. Pesticide-ridden lawn above, formaldehyde-pumped bodies below within conventional cemetery.
Life. Green burial with mature forest at Honey Creek Woodlands.

REFERENCES:

1. Harris, Mark. Grave Matters: A Journey Through the Modern Funeral Industry to a Natural Way of Burial. Scribner, 2007. pp. 40, 41.

2. Harris, Mark. Grave Matters: A Journey Through the Modern Funeral Industry to a Natural Way of Burial. Scribner, 2007. pp. 40, 56.

3. Harris, Mark. Grave Matters: A Journey Through the Modern Funeral Industry to a Natural Way of Burial. Scribner, 2007. pp. 30, 39.

4. Harris, Mark. Grave Matters: A Journey Through the Modern Funeral Industry to a Natural Way of Burial. Scribner, 2007. p. 38.

5. Harris, Mark. Grave Matters: A Journey Through the Modern Funeral Industry to a Natural Way of Burial. Scribner, 2007. p. 61.

Shelter for ceremonies and gatherings at Honey Creek Woodland

Garden Hose Dangers and Recommendations

Tuesday, July 28th, 2009

© 2009 Brad Lancaster, www.HarvestingRainwater.com

Many garden hoses leach lead and other chemicals into the water as it sits in the hose. Polyvinyl chloride (PVC) and brass fittings are often the culprits.

Yuck - the water tastes like lead!
Yuck - the water tastes like lead!

To reduce such risk, purchase, use, and/or drink only from hoses labeled safe for drinking water. Never buy any hose with such labeling as "WARNING: This product contains a chemical in the State of California to cause cancer and birth defects or other reproductive harm." Note that such warnings will typically be in very small print.

A May 2005 Consumer Reports article, "Dare you drink from a garden hose?" reports that hoses labeled safe for drinking leach minuscule concentrations of lead into water standing in the hose, while hoses not labeled drinking water safe leached up to 10 to 100 times allowable lead levels into water standing in the hose.

So, flush any hose before you drink from it by letting the water run a while before you gulp.

Suppliers of hoses labeled safe for drinking water include:

Gatorhyde Drinking Water Safe Garden Hose
Armadillo Hoses

Note that these are far better than most, but not perfect. Gatorhyde contains polyurethane, while Armadillo contains a less toxic PVC. Both polyurethane and PVC are banned materials in the Living Building Challenge Materials Red List (Prerequisite Five). The Living Building Challenge is an integrated green building guide that goes well beyond LEED.

Note for anyone using gravity to move water through a hose from a rainbarrel or rainwater tank - get 3/4-inch (best) or 5/8-inch (next best) interior diameter hose instead of 1/2-inch interior diameter. The larger the interior diameter, the less surface friction will reduce your low gravity-fed pressure.

Also make sure your rainbarrel or cistern faucet does not constrict its interior diameter to less than 3/4 of an inch. Look inside the valve. Unfortunately, most readily available valves reduce interior diameter to 1/4 of an inch, greatly reducing your gravity-fed pressure.

Harvesting Urban Drool

Wednesday, July 22nd, 2009

© 2009 Brad Lancaster, www.HarvestingRainwater.com

All around the world I see water wastefully flowing down urban street curbs and out of concreted storm drains even though it has not rained in months. It is not stormwater I see flowing. It is urban drool. Others call it “nuisance runoff” – water from leaky pipes, driveway car washes, over-watered landscapes, and so on – our waste.  But it can be a resource. It can be harvested.

Brad Lancaster
Urban drool running down concreted channel Tujunga Wash, Los Angeles, California. Photo credit: Brad Lancaster

That is what is happening in Los Angeles, California, along a mile-long stretch of the Tujunga Wash Flood Control Channel between Vanowen Street and Oxnard Avenue. It is bringing myriad forms of life back to this community.

Between 1950 and 1952 the U.S. Army Corps of Engineers cleared a 9-mile section of the waterway of its vegetation and lined it with concrete in order to drain the water out of the community as quickly as possible. The goal was flood control, but it also dehydrated the watershed and its aquifer, removed the natural water filter, and created a fenced-off sterile blight.

img_8099
Section of Tujunga Wash and fenced-off upper bank pre-rehabilitation. Photo credit: Brad Lancaster

That is now beginning to be reversed with the Tujunga Wash Greenway and Stream Restoration Project. A stream has been recreated and replanted with native riparian vegetation on the upper banks of the concreted channel. The new stream is fed by water diverted upstream from the channel through a half-mile-long pipe. Much of this water is urban drool, which flows year round. As the water flows through the greenway, it is filtered and cleaned by sand, gravel, and tree roots. Some percolates into the ground (helping recharge the aquifer); the rest is returned to the flood-control channel via another pipe. It teems with life and invites one to step off the wide pedestrian/bicycle path lining the stream to explore and play.

Section of Tujunga Wash and new pedestrian path/corridor post rehabilitation
Section of Tujunga Wash and new pedestrian path/corridor post rehabilitation. Photo credit: Brad Lancaster

Much of this life acts as a living seed-bank for indigenous plants, whose seed can help revegetate both downstream areas as water and seed flow downstream, and upstream areas as wildlife walks and flies upstream with seed in tow.

As this life resides on the upper banks it is unlikely to be washed out in big floods. The floods will scour down the concreted channel, leaving the life in its protective upper bank eddy to replant what is scoured – and to germinate still more life not yet seen.

Brad Lancaster
Playing in section of Tujunga Wash rehabilitated upper bank stream. Photo credit: Brad Lancaster

It is a small step. A beginning. An invitation to revalue and rehabilitate our waterways so they once again are regenerative corridors of water, pedestrians, and wildlife.

For more on this dynamic project see:

http://www.coastandocean.org/coast_v23_no4_2007-08/articles/tujunga_01.htm
and
http://ladpw.org/apps/news/pdf/2380_2618.pdf

For more ideas, strategies, and stories on how to harvest urban drool and rainwater runoff to generate more life higher in the watershed of our built environments see:
-    Street Orchards for Community Security
-    Parking Lot to Parking Orchard
-    Farming in the City with Runoff from a Street and
-    Rainwater Harvesting for Drylands and Beyond, Volume 2: Water-Harvesting Earthworks

And thank you to David O’Donnell of TreePeople for guiding me to this project and its resources.

Street Orchards for Community Security

Monday, July 6th, 2009

© Brad Lancaster, www.HarvestingRainwater.com
Drops in a Bucket Blog

My view of public streets was radically changed when I heard ecovillage designer Max Lindigger tell the story of an insightful walk he took with his grandfather. “Look there,” said his grandfather, pointing to condominiums being built on the once-forested slopes above his village in the Swiss Alps. “That’s where we grew and gathered food during the war. The forests were common land, a reserve of community resources. What commons remain? Where will we grow and gather our food in the next catastrophe?”

I then looked at my Sonoran desert city of Tucson, Arizona, and asked myself, “Where are my community’s forests, our commons? Where would we get our food in times of need?”

Over 450 native food plants grow wild in the intact areas of the Sonoran Desert.1 The velvet mesquite tree is one of the keystone species, producing a reliable crop of diabetes-deterring, naturally sweet, protein- and carbohydrate-rich seeds and seedpods in both wet years and drought.2 Thus it used to be a staple of the indigenous people’s diets. Yet the vast majority of these trees and the greater ecosystem have been bulldozed within my city to be replaced with a hot and inhospitable pavement of impermeable streets, parking lots and buildings or landscapes of water-hungry exotic plants dependent upon irrigation from dwindling water supplies. The pavement drains much of our scant 12 inches (305 mm) of average annual rainfall out of the community through runoff and evaporation. Yet, this pavement is also the excessively long corridor by which most of our food arrives. According to the WorldWatch Institute, the average American meal travels 1,500 to 2,500 miles (2,400 to 4,000 km) from the farm to the table.3 If oil supplies that fuel semi-trailers disappeared we’d be without food. If the power that fuels our well pumps went out, we’d be out of water. We are creating the conditions for catastrophe.

But that can change by turning “wastes” into resources, and turning challenges into opportunity. The majority of public land—our commons—in the urban setting is our public streets and adjoining right-of-ways. All too often there is little or no vegetation there, let alone a forest. But the resources (soil, local-nursery- and backyard-grown native plants, rainwater runoff, and people) to grow a forest, or at least regionally appropriate orchards, are there (figs. 24 and 25).

Once established, native food plants can survive on our natural rainfall patterns without irrigation. With harvested rainfall these plants can thrive. The vast majority of Tucson’s stormwater runoff is currently diverted straight from roofs, driveways, patios, parking lots, and convex landscapes to public streets that flood to resemble rivers; the runoff then exits via storm drains (fig. 26). If we recognize runoff as an asset rather than a liability, we can harvest it before it runs down the drain, and with it, sustainably grow native food forests on public rights-of-way along the neighborhood streets that act like ephemerally flowing riverbeds, and within public parks and on private property (fig. 27). This also greatly reduces potential flooding of downstream areas, while improving stormwater quality.

That’s a big part of the idea behind a collaborative effort in my hometown called Desert Harvesters, which strives to promote, celebrate, and enhance local food production and security by planting indigenous, food-bearing shade trees in water-harvesting earthworks, and then showing folks how to harvest and process the bounty. Annual events include neighborhood tree plantings, milling events that grind mesquite seedpods harvested from neighborhood trees into delicious flour, and native/local food feasts.

Planting Community Roots
We encourage neighborhood activists to organize tree plantings in their communities, emphasizing hardy, food-producing shade trees native to the Tucson Basin. We provide a list of the recommended trees, their description, and some of their uses on our website. These trees are the best for the area, since they have adapted over millennia to our local climate and soils, and coevolved with the native wildlife.

Neighbors can purchase these trees in 5-gallon sizes for just $8 each thanks to generous subsidies from Tucson Electric Power Company and the local program Trees for Tucson. A community tree-planting day is set for each neighborhood to distribute their trees, and it’s kicked off with a free workshop on how to plant them in water harvesting earthworks. Volunteer crews of neighborhood residents then set out to plant trees along their streets, sidewalks, and in private yards. Within hours of planting the neighborhood feels changed for the better — more neighbors know each other, the trees show the care and commitment people have for their community, and water-harvesting earthworks can be observed by all (fig. 28). Within six years of planting the trees are full and beautiful, regularly blooming with seasonal color. Neighborhoods find that as native habitat grows back within the urban core, exotic pigeon populations start to be replaced by native bird life such as cardinals, flycatchers, cactus wrens, hummingbirds, curve-billed thrashers, white-winged doves, Gambel’s quail, and Gila woodpeckers. The community’s sense of place becomes reconnected to the flora and fauna of the local ecosystem, which is becoming reestablished right outside their homes. Within eight to ten years of planting, the tree-shaded sections of the neighborhood are noticeably cooler than unplanted areas (compare figs. 29 and 30). This confirms what studies have shown — shade trees growing along streets can cool the summer temperatures of urban neighborhoods by 10°F (5.5°C) if the canopy shades enough of the hardscape.4 This can greatly reduce a community’s power consumption since less power is then needed to cool buildings mechanically. Plant a tree and you plant a living air conditioner.

Additional indigenous food trees in the Tucson area include foothills palo verde (Cercidium microphyllum) and blue palo verde (Cercidium floridum), which produce delicious flowers and barley-flavored seeds, and desert ironwood (Olneya tesota), which produces peanut-flavored seeds. Many native plants also have medicinal value and provide craft materials such as dyes, wood, glues, fiber, and more. Native food trees in other regions might include oak, pinyon pine, sugar maple, or date palm.

The Harvest
Harvesting advice is given on our website, and harvesting workshops are given in areas of the community where the trees have been planted. The harvest extends well beyond the picking of fruit and seed. We also try to teach folks to appreciate the value of harvesting the local resources that will support and enhance the trees — such as rainwater runoff and mulch. The implementation of rainwater-harvesting cisterns is encouraged to augment water-harvesting earthworks with captured roof-runoff, and enhanced water-harvesting earthworks are utilized along streets to use street runoff to irrigate passively the trees planted along the streets. This simultaneously enhances local water resources while creating a beautiful, multipurpose greenfrastructure of flood-controlling landscapes. For more information on these strategies, please see my books Rainwater Harvesting for Drylands and Beyond, Volumes 1 and 2 at www.HarvestingRainwater.com.

In addition to harvesting runoff, the basin-like earthworks passively harvest mulch in the form of leaf and fruit drop. The mulch increases the rate at which rainfall is absorbed into the soil, minimizes water loss to evaporation, and naturally fertilizes the soil. Rather than strip-mining nutrients from the trees and soil by raking away fallen leaves and fruit drop (fig. 31), we encourage folks to let this organic matter collect within the basins around the trees to decompose naturally and cycle back into the vegetation and soil (fig. 32). Prunings are cut up into 4-inch (10-cm) long sections and laid beneath the trees from which they were cut. Harvest your leaf drop and prunings, and the nutrient loop becomes regenerative. Trees grow taller and stronger.

Milling and Enjoying Mesquite
We live in a society that is often short on time and in search of convenience. Traditional means of grinding mesquite pods and processing other wild foods often demand more time than busy folks are willing to give up. So we sought to speed up the process and make it fun. Thanks to a $4,900 PRO Neighborhoods grant we were able to purchase a farm-scale hammermill and mount it to a trailer to make it mobile. We take the mill to various public, community milling events to which folks can conveniently bring their harvested mesquite pods (fig. 33). The hammermill can grind 5 gallons of whole mesquite pods into 1 gallon of finely textured, naturally sweet flour in just 5 minutes. Traditionally this would’ve taken hours (fig. 34).

The milling events are typically held in conjunction with local farmers’ markets or mesquite pancake feasts to enhance the diversity of available foods and to expose folks to the wonderful flavors and potential abundance of locally grown foods. The events are organized in October and November at community gardens, the community food bank, and community centers, to correspond with the late summer garden harvest and the end of the mesquite pod harvest. Mesquite pancakes served with prickly pear and saguaro syrups or backyard honey “plant the seeds” of the native foods’ delicious tastes and potential within the minds and palates of the hungry public (fig. 35). (Click here for a video of one of the community fiestas.) The sale of, and feasting on, local garden produce like corn, squash, tomatoes, and tepary beans, and cultural foods like tamales, sweet potato pie, and pickled cholla buds are encouraged. Local musicians play as folks eat and the hammermill is fired up to grind the mesquite pods brought by community members who harvested over the summer. Flour goes home with the harvesters, and mesquite breads, cookies, and sauces are cooked up in their kitchens.

By planting, harvesting, and sharing the produce of the native ecosystem and backyard gardens these foods become sustainable parts of our daily experience, community/cultural identity, and food security. Many of these plants, particularly the natives, do not need imported resources to grow. By incorporating such strategies as water harvesting, passive mulching, and strategic planting (such as along streets or on the east and west sides of buildings), local resources are enhanced, wildlife can prosper, neighborhoods are beautified, and communities are made more liveable. By sharing and celebrating community efforts and resources knowledge is spread, the value and appreciation of local resources grows, and community ties and investment build. All of this is an integrated means of designing to thwart catastrophe, while enhancing our lives now. And the benefits steadily grow both with the trees, the relationships we have initiated with our neighbors, and a deeper connection to place and the resources that sustain it.

Brad Lancaster is a permaculture teacher, designer, consultant, and activist living in Tucson, Arizona. He is a co-founder of Desert Harvesters. In addition, he is the author of the award-winning books Rainwater Harvesting for Drylands and Beyond, Volumes 1 and 2 at www.HarvestingRainwater.com.

The potential of harvested street runoff5
For every inch of rainfall
• A 10-foot wide paved street will drain 27,800 gallons of runoff per mile
• A 20-foot wide paved street will drain 55,700 gallons of runoff per mile
• A 30-foot wide paved street will drain 83,500 gallons of runoff per mileFor every 100 mm of rainfall
• A 3-m wide paved street will drain 300,000 liters of runoff per mile

• A 6-m wide paved street will drain 600,000 liters of runoff per mile

• A 9-m wide paved street will drain 900,000 liters of runoff per mile

References:
1. Hodgson, Wendy, Food Plants of the Sonoran Desert, University of Arizona Press, 2001.
2. Niethammer, Carolyn J., The Tumbleweed Gourmet – Cooking with Wild Southwestern Plants, University of Arizona Press, 1987.
3. Halweil, Brian, Home Grown – The Case For Local Food in a Global Market, WorldWatch Paper 163, WorldWatch Institute, 2002.
4. Hammond, Johnathan, Marshall Hunt, Richard Cramer, and Lauren Neubauer, A Strategy for Energy Conservation – Proposed Energy Conservation and Solar Utilization Ordinance for the City of Davis, California, City of Davis, CA Energy Conservation Ordinance Project, 1974.
5. Lancaster, Brad. Rainwater Harvesting for Drylands and Beyond, Volume 2: Water-Harvesting Earthworks, Rainsource Press, 2008.

Farming in the City with Runoff from a Street

Thursday, June 25th, 2009

© Brad Lancaster, Drops in a Bucket Blog, www.HarvestingRainwater.com.

The following is one of my favorite water-harvesting stories. It comes from one of my mentors, Russ Buhrow, and has inspired me in much of my work. It is amazing what Russ produced with stormwater, something too many people consider to be a waste or a liability, but as Russ shows, is actually a great resource.

In summer 1980, plant sciences graduate student Russ Buhrow decided to take a break from the books to gain "hands-on" knowledge by dryfarming in the middle of the simmering desert city of Tucson, Arizona, where annual rainfall averages 12 inches (305 mm). Taking his cue from the ancient traditions of indigenous Tohono O'odham, Russ raised his crops solely on direct rainfall and runoff harvested from short bursts of sporadic summer monsoon rains. Yet Russ's situation was somewhat different from his Native American neighbors. He didn't farm alluvial flats of a healthy desert ecosystem where runoff from surrounding mountains flows down a braiding arroyo to a field. Instead, he farmed a semi-urban vacant lot between a dry riverbed and cinder block apartment buildings. Rather than intercepting runoff from low desert mountains and foothills, Russ learned to harvest runoff from rooftops, yards, parking lots, and a city street.

Russ began by observing the gradually sloping arable vacant lot. Wheel ruts crisscrossed it. Random piles of compacted debris were strewn about, and dense weeds grew in depressions where rainwater and organic matter collected. "Ah ha!" thought Russ. "The weeds grow where the water is, so that's where my garden will go!"

With permission from the landowner he dug several 8- x 8-foot (2.4- x 2.4-m) sunken garden beds where the weeds grew tallest. Berms stretched to either side on the downslope side of his basins like open arms of a big welcoming hug for rainwater runoff (see Fig. 11, after article, for the multi-year progression of Russ' fields). He planted seeds as the summer storms rolled in. Thunder cracked, lightening flashed, and the rain came down in sheets. Russ stood in the middle of it all and watched. He saw water pool in the garden basins. He also noticed water pouring off a parking lot just upslope of the basins and quickly dug a ditch as a diversion swale, directing runoff from parking lot to garden.

After 40 minutes the rain stopped. With the soil now saturated, his seeds germinated in just 3 to 5 days. Russ was full of adrenaline. As he says, "When you see the rain flow like that, it's a EUREKA moment. You see the water and realize, this really works!" The parking lot ditch had just increased his water resources five-fold. He went right to work, expanding his planting area to 700 square feet (65 m²).

From then on, no matter how far away he was, Russ always ran to the garden when rain started to fall. "It's amazing how much water you can catch in neighborhoods," he says. "You just need to watch the sheet flow when it rains." Rain and runoff revealed the land's subtle slopes and depressions. He saw how much water flowed and where. Then he figured out how to catch and use it.

For Russ this was a rush - like playing "flood" in a huge sandbox, with lightening! The unlocked car was always nearby so he could leap in when the lightening struck too close.

By fall, drought-hardy tepary beans, black-eyed peas, corn, squash, and devil's claw (a fiber plant with edible seeds and okra-like immature fruit) were harvested–all irrigated only by rain (Figs. 1, 2, 3).

In winter the fields went fallow, but Russ stayed active. Once, standing in the rain, he saw excessive runoff rushing down Columbus Boulevard, an asphalted arterial street that dead ended 400 yards (360 m) from his garden. "FREE WATER!" Russ yelled. He dug a 1/4-mile (0.8 km) long diversion swale/ditch from the street to his garden (Fig. 4A and Fig. 4B). He reworked the old garden beds and added new ones. When finished, the garden basins ranged from 100 to 700 square feet (9-63 m²) each. Together they resembled a series of stepped terraces that directed overflow water from the upper gardens to the lower gardens (Figs. 5, 6, 7, 8). The combined planting area was now 1/2 acre (0.1 ha).

That summer two big storms flooded the long swale with water 8 inches (20 cm) deep and 2-3 feet (60 - 90 cm) wide. Both storms lasted less than an hour and made Russ run through the garden, euphoric from the water, terrorized by lightening, and exhausted by effort. With the diversion swale running above (upslope of) the top of the terraced garden basins, Russ could temporarily divert the flow into a specific field by cutting an opening in the swale's berm, then blocking the water's flow within the swale at a location just downslope of the cut, to force more flow into this field. He created this "blockage" by throwing wads of weeds and brush into the swale and packing them down with his shovel, his feet, and rocks, then piling dirt behind the brush. Next, he'd run down the swale to the next field, and make a new cut in the berm and a new barrier just downslope of it. Running back up to the first diversion Russ would wait until the first field was well watered, then remove the original barrier of weeds, rock, and soil, and use this material to plug the cut in the berm so the water flowed down the main swale again. That done, he'd run down the swale to make sure the second cut and barrier were diverting water into his second field. If all was well, he'd dash off to the next field for another diversion cut and barrier. And so on, until the water stopped flowing.

Russ estimates he was harvesting as much as 2-3 acre-feet of runoff water a year. That's 653,400 to 980,100 gallons, or 2,970,000 to 4,455,000 liters. "You had to be there when it rained, and haul ass!" Russ explains. "All could be over within 30 minutes of the first raindrop."

Russ was passionate about harvesting water, but he made sure he didn't collect more than could infiltrate into the soil. If water sits on the soil's surface for more than two or three days it can activate a denitrifying bacteria (caused by a lack of oxygen in the soil), which can decrease soil fertility. Yellow spots in fields where water ponds for several days indicate denitrification. Russ prevented such problems by spreading water throughout the landscape, improving the soil's water-absorbing capacity with organic matter and vegetation, and having adequate spillways for overflow water.

As surplus water overflowed from his fields and moistened the soil beyond and below his gardens, Russ expanded his garden by constructing new sets of terraced fields, each with raised berms to retain overflow water from the fields above (fig. 11). He soon had a full acre (0.4 ha) cultivated with corn, tepary and lima beans, Mixta and Moschata squash, devil's claw, watermelon, sunflowers, cow peas, and, in a wet fall and winter, I'itoi onions and artichokes (Figs. 12, 13, 14).

Just two decent summer storms, spaced well apart, were enough to support his crops. Russ planted hardy heirloom seeds of dryland crops in coordination with the first good summer rain (see Notes 1 and 2 at end of article). He harvested runoff from rainfalls as light as a tenth of an inch.

Only once in five years did Russ's fields fail. The rains just wouldn't cooperate. They were too little, spaced too close together, or too far apart. But when they did cooperate the fields were very productive. One year, he harvested 2 tons of mature squash along with another ton of calabacitas (immature squash) - 400 lbs (180 kg) picked on one day alone. Harvests of 17,000 devil's claw (the young fruits are eaten like okra, the dried fiber is used for traditional basket making) in a good season were common.

Russ had no money for tractors, pumps, pesticides, or water. But he also had no debts since he took no loans. Working with natural cycles his only significant investment was his time. Russ describes those times as some of the happiest of his life.

For 10 years Russ farmed within the sprawling city of Tucson, relying solely on runoff from desert rains for water. He did not contribute to groundwater depletion and provided a lot of fresh produce for his family, friends, and neighbors. He was connected with the natural elements–"If you're not, you fail," he says. For Russ, this connection was perhaps the greatest benefit of his work, making him feel rooted, part of the natural flow of wind, rain, and sun. Through daily observation he gained numerous insights into the cycles of the Sonoran Desert.

Russ is rarely concerned about food these days. He knows he can grow it - even in the low desert. "All you need is rain," he says, "and we have enough."

Enough, that is, if we recognize and value it.

In 1990 Russ went to the Cape Verde Islands, off West Africa, where he used his experience as a reference for part of a USAid study of the islands' forms of agriculture and diversity of locally adapted food crops. After 3 months he returned and took a full-time job as grounds curator at Tohono Chul Park, where he has created a number of water harvesting features - including the Jardin Sin Aguas. Russ gives presentations on water harvesting and has a private consultation and design business.

Rain-irrigated cowpeas
Fig. 1. Rain-irrigated cowpeas. Photo courtesy of Russ Buhrow
Rain-irrigated tepary beans
Fig. 2. Rain-irrigated tepary beans. Photo courtesy of Russ Buhrow
Rain-irrigated squash
Fig. 3. Rain-irrigated squash. Photo courtesy of Russ Buhrow
Fig. 4A Diversion ditch dry
Fig. 4A. Diversion swale - dry. Photo courtesy of Russ Buhrow
Fig. 4B. Diversion ditch wet
Fig. 4B. Diversion swale full of captured runoff. Photo courtesy of Russ Buhrow
Fig. 5. Runoff irrigated gardens. Roof runoff from building in the background is caught in the diversion swale, and directed to the gardens. Photo courtesy of Russ Buhrow
Fig. 6. Runoff flowing from upper terraced garden to a lower garden. Christopher City apartment buildings in the background. Photo courtesy of Russ Buhrow
Fig. 7. Harvested runoff flowing from an upper field to a lower field. Photo courtesy of Russ Buhrow
Fig. 8. Spillway from upper field to lower field stabilized with rock. Photo courtesy of Russ Buhrow
Fig. 9. Watershed or catchment for Russ' farm. North-south road, left of apartment complex is Columbus Blvd. East-west road above apartments is Ft. Lowell. Dotted line through Christopher City apartment complex represents ridgeline of subwatershed draining toward Columbus Blvd and Russ' diversion swale. Area in rectangle is enlarged in next figure. Rillito river bed is at the bottom (or north end) of the drawing. Illustration by Silvia Rayces
Fig. 10. Close up of Russ' farm (bottom right), parking lot and it's diversion swale draining to farm, and drainage ditch directing Columbus Blvd runoff to farm. Illustration by Silvia Rayces
Fig. 11. Multi-year progression of Russ' farm from a single garden bed in upper left corner to a 1-acre farm in lower right corner. Dark, wide lane appearing in 4th progression, represents the diversion swale and its expansion. Illustration by Silvia Rayces
Fig. 12. Russ standing in field. Photo courtesy of Russ Buhrow.
Fig. 13. Child in a bountiful field of cowpeas. Photo courtesy of Russ Buhrow
Fig. 14. Kids in fields of squash and devil's claw. Photo courtesy of Russ Buhrow

NOTE 1: SOURCE OF DRYLAND-ADAPTED FOOD CROP SEEDS
Native Seeds/SEARCH, 526 N. Fourth Ave., Tucson, AZ 85705. www.nativeseeds.org.

NOTE 2: SPACING PLANTS TO STRETCH SOIL MOISTURE AND BUFFER WINDS
Russ spaced his plantings according to how much moisture was in the soil, the ability of the plants to withstand strong winds, and the expected size of plants at maturity. Spring plantings were spaced further apart than summer plantings, since the plants had to survive on residual soil moisture until the summer monsoons. Plants that were easily blown over or snapped by the wind, such as tepary beans and corn, were planted in clusters to support one another. By using wide spacing that took into account the plants' size at maturity, Russ had easy access for weeding between plants with his roto-tiller and could avoid the use and expense of herbicides.
Tepary beans were planted in groups of 5 seed, each group 4 feet (1.2 m) apart.
Squash seeds were planted in clumps with three seeds each, with clumps spaced 8 feet (2.4 m) apart, or just 4 feet (1.2 m) apart if planted late in the growing season, since they wouldn't get as big before frost hit).
Devil's claw seeds were planted in clumps of three seeds, each 8 feet (1.2 m) apart.

Plants can be spaced closer if soil is deeper and can infiltrate more water. A silt/loam is good for this, while sand is often too porous. Heavy to medium clay soils can work, but watch the percolation rate. Most roots and nutrients will be in the top 2 to 4 feet of the soil.

NOTE 3: HOW MUCH RAINFALL YIELDED HOW MUCH PRODUCE?
In 1981, Russ planted seeds at the end of March after the danger of frosts had passed. He germinated the seeds on residual soil moisture from February storms that dropped 1.02 inches (25.9 mm) of rain, and another 2.1 inches (53 mm) of rain in March. The plants got an additional 3.6 inches (91 mm) in April, and 0.45 inches (11 mm) in May. Although this was a wet year for the desert, the plants had to survive without any more water for over a month and a half. In July the rains started again, with 2.71 inches (68 mm) falling that month, 0.26 inches in August (6.6 mm), 0.47 inches in September (11.9 mm), and no rain in October. On that rainfall alone, the garden produced 9 tons (8.1 t) of Mixta squash per acre and 26,000 devil's claw along with corn, watermelon, tepary beans, and sunflowers.

NOTE 4: THE LOSS OF ARABLE LAND
Russ Buhrow's runoff farm no longer exists. It has since been built over with a new housing development. Houses built within the floodplain upon some of the area's most fertile soils. If we keep building on, and paving over, our best agricultural land - where will we grow our community's food?

NOTE 5: POTENTIAL CONTAMINANTS IN STREET RUNOFF
I think more research is needed in the area of street runoff toxins, and where they end up. Russ tells me he experienced no problems on his farm or with his produce grown a 1/4 mile from the road itself. I have never had any problems with plant health where plants have been irrigated with street runoff. The plants have thrived. In street-side, street runoff harvesting basins I harvest the fruit from the plants irrigated with street runoff, but I make sure none of the fruit has come into direct contact with the street runoff. Thus I harvest fruit from trees (mesquite pods, desert ironwood seeds, olives, pomegranates, etc). I do not grow leafy green or tuber crops in these basins. More info on my experiences can be found in

NOTE 6: MORE RESOURCES
Rainwater Harvesting for Drylands and Beyond, Volume 1: Guiding Principles to Welcome Rain into Your Life and Landscape by Brad Lancaster. www.HarvestingRainwater.com
Rainwater Harvesting for Drylands and Beyond, Volume 2: Water-Harvesting Earthworks by Brad Lancaster. www.HarvestingRainwater.com
Water-Harvesting from Low Standard Rural Roads by Bill Zydeek. www.QuiviraCoalition.org
• "Street Orchards for Community Security" found at the bottom of the webpage http://www.desertharvesters.org/pressvideostories/

Create the Conditions for Catastrophe…or Resource Management for Community Security

Monday, January 19th, 2009

My view of public streets was radically changed when I heard ecovillage designer Max Lindigger tell a story of an insightful walk he took with his grandfather. “Look there,” said his grandfather, pointing to condominiums being built on the once forested slopes above his village in the Swiss Alps. “That’s where we grew and gathered food during the war. The forests were common land, a reserve of community resources. What commons remain? Where will we grow and gather our food in the next catastrophe?”

I then looked at my Sonoran desert city of Tucson, Arizona and asked myself, “Where are my community’s forests, our commons? Where would we get our food in times of need?”

Over 450 native food plants grow wild in the intact areas of the Sonoran Desert.1 The velvet mesquite tree is one of the keystone species producing a reliable crop of diabetes-deterring, naturally sweet, protein and carbohydrate—rich seeds and seedpods in both wet years and drought.2 Thus it used to be a staple of the indigenous people’s diets. Yet the vast majority of these trees and the greater ecosystem have been bulldozed within my city to be replaced with a hot and inhospitable pavement of impermeable streets, parking lots and buildings or landscapes of water-hungry exotic plants dependent upon irrigation from dwindling water supplies. The pavement drains much of our scant 12 inches (304 mm) of average annual rainfall out of the community through runoff and evaporation. Yet, this pavement is also the excessively long corridor through which most of our food arrives. According to the WorldWatch Institute, the average American meal travels 1,500 to 2,500 miles (2,414 to 4,023 km) from the farm to the table.3 If oil supplies fueling semi-trailers disappeared we’d be without food. If the power that fuels our well pumps went out, we’d be out of water. We are creating the conditions for catastrophe.

But that can change by turning “wastes” into resources, and turning challenges into opportunity. The majority of public land—our commons—in the urban setting is our public streets and adjoining right-of-ways. All too often there is little or no vegetation there, let alone a forest. But the resources (soil, local nursery and backyard grown native plants, rainwater runoff, and people) to grow a forest, or at least regionally appropriate orchards, are there (fig. 24 and 25).

The Heat Island Effect
Fig. 24. The heat island effect. An excessively wide, exposed, solar-oven-like residential street in Tucson, Arizona absorbs the sun’s heat during the day like a battery, then radiates it out at night. This local warming effect has raised summer temperatures in Tucson by 6°F (3°C) since the 1940s, which contributes to global warming since the higher temperatures result in people using air conditioners more, which are powered by electricity generated through the burning of coal. Note that no shade trees are planted in the public right-of-way along the street, leaving street and sidewalk baked. All runoff is drained off site leaving the development dehydrated. Reproduced with permission from Rainwater Harvesting for Drylands and Beyond, Volume 1.

Fig. 25. The cool island effect.
Fig. 25. The cool island effect. A narrow, mature tree-lined, and shaded street in Village Homes, Davis, California. This local cooling effect from shading has resulted in summer temperatures dropping 10°F (5.5°C), which reduces global warming since lower temperatures result in people using air conditioners less, which are powered by electricity generated through the burning of coal. Note that runoff from the street is directed to the trees that shade the street; beneficially hydrating the site, while also reducing downstream flooding. The trees are deciduous, so they drop their leaves and let more sun in during winter. Reproduced with permission from Rainwater Harvesting for Drylands and Beyond, Volume 1.

Once established, native food plants can survive on our natural rainfall patterns without irrigation. With harvested rainfall these plants can thrive. The vast majority of Tucson’s stormwater runoff is currently diverted straight from roofs, driveways, patios, parking lots, and convex landscapes to public streets that flood to resemble rivers; the runoff then exits via storm drains (fig. 26). If we recognize that runoff as an asset rather than a liability, we can harvest it before it runs down the drain to sustainably grow native food forests on public rights-of-way along the neighborhood streets that act like ephemerally flowing riverbeds, and within public parks and on private property (fig. 27). This also greatly reduces potential flooding of downstream areas, while improving stormwater quality.

Fig. 26. A landscape wastefully draining resources away.

Fig. 26. A landscape wastefully draining resources away. Reproduced with permission from Rainwater Harvesting for Drylands and Beyond, Volume 1.

Fig. 27. A landscape abundantly harvesting resources.

Fig. 27. A landscape abundantly harvesting resources. Reproduced with permission from Rainwater Harvesting for Drylands and Beyond, Volume 1.That’s a big part of the idea behind a collaborative effort in my hometown called Desert Harvesters, which strives to promote, celebrate, and enhance local food production and security by planting indigenous, food-bearing shade trees in water-harvesting earthworks, and then showing folks how to harvest and process the bounty. Annual events include neighborhood tree plantings, milling events that grind mesquite seedpods harvested from neighborhood trees into delicious flour, and native/local food feasts.

Planting Community Roots
We encourage neighborhood activists to organize tree plantings in their communities, emphasizing hardy, food-producing shade trees native to the Tucson Basin. We provide a list of the recommended trees, their description, and some of their uses on our website. These trees are the best for the area, since they have adapted over millennia to our local climate and soils, and coevolved with the native wildlife.

Neighbors can purchase these trees in 5-gallon sizes for just $8 each thanks to generous subsidies from Tucson Electric Power Company and the local program Trees for Tucson. A community tree-planting day is set for each neighborhood to distribute their trees, and it’s kicked off with a free workshop on how to plant them in water harvesting earthworks. Volunteer crews of neighborhood residents then set out to plant trees along their streets, sidewalks, and in private yards. Within hours of planting the neighborhood feels changed for the better-more neighbors know each other. The trees show the care and commitment people have for their community, and water-harvesting earthworks can be observed by all (fig. 28). Within six years of planting the trees are full and beautiful, regularly blooming with seasonal color. Neighborhoods find that as native habitat grows back within the urban core, exotic pigeon populations start to be replaced by native bird life such as cardinals, flycatchers, cactus wrens, hummingbirds, curve-billed thrashers, white-winged doves, gamble’s quail, and gila woodpeckers. The community’s Sense of Place becomes reconnected to the flora and fauna of the local ecosystem, which is becoming reestablished, right outside their homes. Within eight to ten years of planting, the tree-shaded sections of the neighborhood are noticeably cooler than unplanted areas (compare figs. 29 and 30). This confirms what studies have shown - shade trees growing along streets can cool the summer temperatures of urban neighborhoods by 10°F (5.5°C) if the canopy shades enough of the hardscape.4 This can greatly reduce a community’s power consumption since less power is then needed to mechanically cool buildings. Plant a tree and you plant a living air conditioner.

Fig. 28. Happy tree planters and newly planted desert ironwood tree.
Fig. 28. Happy tree planters and newly planted desert ironwood tree. Neighbors help each other plant trees, and thereby get to know one another and create a more dynamic, close-knit community. Photo credit: Brad Lancaster

Fig. 29. Dunbar/Spring right-of-way before water-harvesting earthworks and tree planting, 1994.
Fig. 29. Dunbar/Spring right-of-way before water-harvesting earthworks and tree planting, 1994. Used with permission from Rainwater Harvesting for Drylands and Beyond, Volume 1.

Fig. 30. Same section of Dunbar/Spring right-of-way as fig. 29 after water-harvesting earthworks and tree planting, 2006.
Fig. 30. Same section of Dunbar/Spring right-of-way as fig. 29 after water-harvesting earthworks and tree planting, 2006. Used with permission from Rainwater Harvesting for Drylands and Beyond, Volume 1.

Additional indigenous food trees in the Tucson area include foothills palo verde (Cercidium microphyllum) and blue palo verde (Cercidium floridum) producing delicious flowers and barley flavored seeds, and desert ironwood (Olneya tesota) producing peanut-flavored seeds. Many native plants also have medicinal value and provide craft materials such as dyes, wood, glues, fiber, and more. Native food trees in other regions might include oak, pinyon pine, sugar maple, or date palm.

The Harvest
Harvesting advice is given on our website, and harvesting workshops are given in areas of the community where the trees have been planted. The harvest extends well beyond the picking of fruit and seed. We also try to get folks to realize the value of harvesting the local resources that will support and enhance the trees - such as rainwater runoff and mulch. The implementation of rainwater-harvesting cisterns is encouraged to augment water-harvesting earthworks with captured roof runoff, and enhanced water-harvesting earthworks are utilized along streets to use street runoff to passively irrigate the trees planted along the streets. This simultaneously enhances local water resources while creating a beautiful, multi-purpose greenfrastucture of flood-controlling landscapes. For more information on these strategies please see my books “Rainwater Harvesting for Drylands and Beyond, Volumes 1 and 2” at www.HarvestingRainwater.com.

In addition to harvesting runoff, the basin-like earthworks passively harvest mulch in the form of leaf and fruit drop. The mulch increases the rate at which rainfall is absorbed into the soil, minimizes water loss to evaporation, and naturally fertilizes the soil. Rather than strip mining nutrients from the trees and soil by raking away fallen leaves and fruit drop (fig. 31), we encourage folks to let this organic matter collect within the basins around the trees to naturally decompose and cycle back into the vegetation and soil (fig. 32). Prunings are cut up into 4-inch (10-cm) long sections and laid beneath the trees from which they were cut. Harvest your leaf drop and prunings, and the nutrient loop becomes regenerative. Trees grow taller and stronger.

Fig. 31. Wastefully using fossil fuels to vacuum up leaf drop and nutrients.
Fig. 31. Wastefully using fossil fuels to vacuum up leaf drop and nutrients. Photo credit: Jenny Leis

Fig. 32. Beneficially using prunings as mulch to recycle nutrients back into the soil and tree, while increase water infiltration into the soil, and reducing soil moisture loss to evaporation.

Fig. 32. Beneficially using prunings as mulch to recycle nutrients back into the soil and tree, while increase water infiltration into the soil, and reducing soil moisture loss to evaporation. Photo credit: Brad Lancaster

Milling and Enjoying Mesquite

We live in a society that is often short on time and in search of convenience. Traditional means of grinding mesquite pods and processing other wild foods often demand more time than busy folks are willing to give up. So we sought to speed up the process and make it fun. Thanks to a $4,900 PRO Neighborhoods grant we were able to purchase a farm-scale hammermill and mount it to a trailer to make it mobile. We take the mill to various public milling events around the community to which folks can conveniently bring their harvested mesquite pods (fig. 33). The hammermill can grind 5 gallons of whole mesquite pods into 1 gallon of finely textured, naturally sweet flour in just 5 minutes. Traditionally this would’ve taken hours (fig. 34).

Fig. 33. By taking our mill to various locations it is very easy for folks to get to the events by our favorite non-polluting, community-building, good health modes of transport – foot, rollerblade, skateboard, and bicycle.
Fig. 33. By taking our mill to various locations it is very easy for folks to get to the events by our favorite non-polluting, community-building, good health modes of transport – foot, rollerblade, skateboard, and bicycle. Photo credit: Brad Lancaster

Fig. 34. Primitive mesquite milling demonstration at the Dunbar/Spring Organic Community Garden mesquite milling and mesquite pancake breakfast.
Fig. 34. Primitive mesquite milling demonstration at the Dunbar/Spring Organic Community Garden mesquite milling and mesquite pancake breakfast.

The milling events are typically held in conjunction with local farmers’ markets or mesquite pancake feasts to enhance the diversity of available foods and to expose folks to the wonderful flavors and potential abundance of locally grown foods. The events are organized in October and November at community gardens, the community food bank, and community centers to correspond with the late summer garden harvest and the end of the mesquite pod harvest. Mesquite pancakes served with prickly pear and saguaro syrups or backyard honey “plant the seeds” of the native foods’ delicious tastes and potential within the minds and palates of the hungry public (fig. 35). (Click here for a video of one of the community fiestas). Sale of, and feasting on, local garden produce like corn, squash, tomatoes, and tepary beans, and cultural foods like tamales, sweet potato pie, and pickled cholla buds are encouraged. Local musicians play as folks eat and the hammermill is fired up to grind the mesquite pods brought by community members who harvested over the summer. Flour goes home with the harvesters, and mesquite breads, cookies, and sauces are cooked up in their kitchens.

Josh Schachter
Fig. 35. Hunger for the delicious mesquite pancake. Photo credit: Josh Schachter

By planting, harvesting, and sharing the produce of the native ecosystem and backyard gardens these foods become sustainable parts of our daily experience, community/cultural identity, and food security. Many of these plants, particularly the natives, do not need imported resources to grow. By incorporating such strategies as water harvesting, passive mulching, and strategic planting (such as along streets or on the east and west sides of buildings) local resources are enhanced, wildlife can prosper, neighborhoods are beautified, and communities are made more liveable. By sharing and celebrating community efforts and resources knowledge is spread, the value and appreciation of local resources grows, and community ties and investment build. All of this is an integrated means of designing to thwart catastrophe, while enhancing our lives now. And the benefits steadily grow both with the trees, the relationships we have initiated with our neighbors, and a deeper connection to place and the resources that sustain it.

The potential of harvested street runoff5

For every inch of rainfall
• A 10-foot wide paved street will drain 27,800 gallons of runoff per mile
• A 20-foot wide paved street will drain 55,700 gallons of runoff per mile
• A 30-foot wide paved street will drain 83,500 gallons of runoff per mile

For every 100 mm of rainfall

• A 3-m wide paved street will drain 300,000 liters of runoff per mile
• A 6-m wide paved street will drain 600,000 liters of runoff per mile
• A 9-m wide paved street will drain 900,000 liters of runoff per mile

References:

1. Hodgson, Wendy, Food Plants of the Sonoran Desert, University of Arizona Press, 2001.
2. Niethammer, Carolyn J., The Tumbleweed Gourmet - Cooking with Wild Southwestern Plants, University of Arizona Press, 1987.
3. Halweil, Brian, Home Grown - The Case For Local Food in a Global Market, WorldWatch Paper 163, WorldWatch Institute, 2002.
4. Hammond, Johnathan, Marshall Hunt, Richard Cramer, and Lauren Neubauer, A Strategy for Energy Conservation - Proposed Energy Conservation and Solar Utilization Ordinance for the City of Davis, California, City of Davis, CA Energy Conservation Ordinance Project, 1974.
5. Lancaster, Brad. Rainwater Harvesting for Drylands and Beyond, Volume 2: Water-Harvesting Earthworks, Rainsource Press, 2008.