Tucson Arizona: Regenerating Parks & Parkways through Biomimicry of Floodplains

2014 Regenerative Parks and Parkways: Local Harvests and Enhancements in Our Community Commons in Tucson Arizona

presented by Brad Lancaster

What is the story of your own place? What is your role in that story? What is the role of your public land (parks, parkways, rights-of-way) in that story? The Santa Cruz River was still a free flowing Sponge-like Drain in 1904 Tucson, Arizona, U.S.A as you can see in the photo below. This river use to flow year round. The Santa Cruz river in 2007 Tucson has been turned into a dredged out straightener &  deeper channel through Tucson as land was considered too valuable on either side for Cottonwood Forests and Mesquite Bosques which once acted to percolate water into the deeper aquafir like a sponge.

Historically the great floods that would occur every 100 years are now beginning to occur every 10 years. Especially after human development paves over the watershed and increases the rate and volume of stormwater flow running off site. No more percolating through sponge-like riparian woodland ecosystems along a meandering river floodplain. Just massive runoff, destruction and wasteful evaporation. The river only flows with un-natural street flooding runoff.

The long distance from which to transport Colorado river water to Tucson also means higher costs and more energy. We ignore, deplete, or pollute our local waters — then import ever more long distant water away from other peoples which must be acquired and transported from elsewhere. The largest consumer of electricity (and single source producer of carbon) in Arizona is the pumping of this water hundreds of miles from the Colorado River.

The average annual rainfall in Tucson is (280 mm) 11 inches Yet more rain falls on the surface area of Tucson in a year of average rainfall, than the annual consumption of Tucson’s water-utility water Said another way, in you were to divide the average annual precipitation falling on Tucson by its population, then divide again by 365 days a year, and you get. Can you image how much water they could save ?

Harvest and utilize on-site water (rainwater, stormwater, greywater, c ondensate, etc) as close as possible to where it falls within the oasis zone (your yard or public landscape strips) - within 30’ (9 m) of catchment surface. The illustrations below show how water falling on manmade infrastructure can be utilized to eventually created a lush garden around the home with beautiful small trees and shrubs for free and in the process drop the surrounding temperature around the house by 10 degrees. Also take note of the large desert trees on either side of a highway berm with culverts & storm runoff ditches on both sides and compare that to the surrounding wildland vegetation further away. Water is concentrated as it runs off the hard solid pavement into the culverts & ditches which in turn provide ideal habitat for larger desert trees and shrubs. This phenomena of large green strips of desert native tree vegetation within the ditches on both sides of desert highways can be seen and observed on all desert highways across the southwest. Pay close arrention nexxt time you travel through on a desert highway. This also provides a perfect blueprint for narrow landscape curb strips and medians to not only beautify, but also counter these man made heat island effects. Thus far main steam conventional science has rejected biomimicry with only a handful coming on board to the solutions introduced by non-scientists. Why is that ??? 

Below here I've gone on to further illustrate through a Google Earth satellite capture of what most all desert roads look like along side the roadways where what runoff does occur ends up in storms ditches on both sides and the effect of enhancing wild desert tree growth of native Paloverdes, Mesquite, Ironwood, etc. Now look beyond the ditches several meters and there is almost nothing by comparison other than tiny grasses or shrubs here and there and often just bare soil. This should well help you to appreciate the next animated illustration that follows regarding roadside landscape strips with desert city neighbourhoods and commercial Parkways.

Image - Google Earth - Route 60 - south of Vicksburg, Arizona

Below here provides an animated visial of Path to Scarcity Path to Abundance • Turns resources into wastes • Relies on the costly and imported • Consumes more than it produces • Disintegrated Drains • Turns ―wastes‖ into resources • Relies on the free and local • Produces more than it consumes • Integrated Harvests

In Tucson, Arizona, they are receiving on average 11 inches [280 mm] of annual rainfall. Most of tthat no doubt in summer monsoonal downpours. One mile of an average residential street runoff into storm drains is over ONE MILLION GALLONS of rainfall per year. That’s enough water to sustainably irrigate 400 native food trees per mile, or one tree every 25 feet on both sides of the street - irrigated by the street. One has to wonder why Southern California is wasting so much time and energy with inefficiently planned and ineptly designed storm runoff infrastructure ???

Above these residents of an early attempt at cutting street curbs was done on Sundays when inspectors were off for the weekend because it was at one time illegal. Later when they had done other streets and proved how envaluable this concept was in creating shady streets with nothing more than rain runoff as opposed to municipal drinking water sources, they then went to the city to legalize the practice. They convinced them how successful it was and they became incentivized, then it later became mandated in new city road construction and renovation.

In the street animation above, they created cutouts in the curb, evenly spaced to produce a half meandering effect of a floodplain storm runoff in a main river channel which spills water off to the side of a main river channel as is meanders back and forth. Of course the same happens on the other side of the street, so the snake-like 'S' movement is complete. So the animated scene above would be the finished product based on anticipated flow of the stormwater. Blow is the storm event and the hoped for result in filling landscape basins from the curb cut eddys and the added benefit not only of harvesting free precious freah water, but removing more water from the drain on down the line, removing road contaminants and less violent additional flow volumes once collective drains enter the natural desert wash. That being the case there world be less damage done to the environment and money saved in repairs by municipal street & flood channel maintenance departments.

Below here is the before and after photos of the house Brad Lancaster and his brother bought years ago in an older Tucson neighbourhood before they created this water harvest concept. 

All these slide presentation photos and video below are Brad Lancaster's work. I don't need to repost everything, but I want to provide something to illustrate what water harvesting was like in the desert citires in the southwestern communities. California in general doesn't do enough of these types of things and they should. I added the google earth image to further illustrate how the phenomena of landscape growth happens for miles on end in middle of nowhere desert areas and how we can ise biomimicry to replicate this within city limits anywhere. Below is a TedxTucson video which came out this past March 2017. It's only about 19 minutes long, but well worth a watch of the history of water havesting in Tucson as presented by Brad Lancaster. This was a supplement to another post on water harvesting concept in biomimicry of meandering floodplains in Southern California, but it was too much material here to add to that post, which is itself an extension or addition to another larger post in draft.

My main water harvesting Post which directs to this one: 

Rain Water Harvesting Infrastructure Design Concepts

References to Brad Lancaster's organization, websites and Slideshare presentation

https://www.slideshare.net/Tucson-water-harvesting

www.HarvestingRainwater.com

www.DesertHarvesters.org