Water wisdom for landscape designers

THE GLOBAL WATER SITUATION
Water is abundant . . .however 98% of it is saltwater .
Of the remaining 2% only 1% is available freshwater
“ In one year, ~ 3.5 million die from water related diseases. = Los Angeles”
Some hydrologists believe we have passed the point of “peak water

Virtual Water
The water that is used to produce what we consume.
It takes:
265 gallons = 1 glass of milk
1320 gallons = small steak
2650 gallons = 1 lb. bag of coffee
25 bathtubs of water = cotton for a single teashirt
The average American consumes 1,500 lbs food/year. It’s estimated that takes 1.5 millions gallons of water to produce. That’s a football field flooded with 4’ of water.
“ We are all used to reading detailed technical data about the nutritional content of food. Maybe it’s time we were given some clues on how much water it took to grow it.” – “As the Rivers Run Dry”, Fred Pearse

WATER PRIVATIZATION
Encouraged by the World Bank and International Monetary Fund. 80% of IMF loans are contingent on privatization.
Critics claim privatization has lead to less availability, greater costs, and less safe drinking water

THE NATIONAL WATER SITUATION
Landscape irrigation accounts for about 33% of all household usage of water.
Total domestic use (everything inside and outside the house) accounts for 1% of total water usage nationwide.
Per capita water usage has dropped in the past 5 years. (USGS, 2005). It is now at levels not seen since 1950.
That water savings has come from increased efficiency in agriculture and industry, and not in domestic water use.

THE OREGON WATER SITUATION
We are headed for a warmer, drier, more extreme temperature change future, according to climate change forecasts.
Average temp. to rise between 3 -7 degrees F.
Our population continues to rise. 3.85 million in the Portland area by 2060 (or double our present population)
Ave. Oregon per capita water usage is ~200 gals/day. Ave Maine per capita water usage is 54 gals/day.
This spring the Portland Water Bureau forecast an 85% increase in water fees by 2016.
More people = More water demand. Warmer /drier climate = less snow pack, more drawdowns of reservoirs, greater extremes in river levels, less stability in water supplies.

Depressed yet?

Who will be our water warriors? Who will be first to fight in the trenches for cause of water wisdom?
YOU ! – The landscape designer

How can designers be water warriors?
Consider xeriscaping.
Hydrozone your plant selections
Reduce turf areas or turf alternatives or accepting the “brown”
Understand the impacts of the size, shape and locations of your bed and turf layouts.
amoeba vs football field
Avoid turf or dense ground cover on slopes
Advise clients on how to choose a water-wise contractor

NO! (Not purely, 100%, nada input)

Questions, questions, questions
What is sustainability?
Are landscapes either sustainable or unsustainable or is there a Middle Way?
Is there such a thing as a 100% sustainable, nada input landscape?

My Chicken Yard

What is Pragmatic Sustainability?

Can Landscape Irrigation be Pragmatically Sustainable?
Ya, You Betcha !

I. Thou shalt hydrozone when you design
Group plants by like water needs
Because of the many microclimate variables and the plant type factors there is no practical accurate way of determining this. But close guestimation is.
California’s WUCOLS (Water Use Classification of Landscape Species)

II. Thou shalt not sprinkle thy trees and shrubs.
Irrigation heads (sprays rotors, impacts)that send water up into the air can lose as much of 50% of the water to evaporation before it reaches the ground
As trees and shrubs grow they block sprinkler patterns
Microirrigation (drip, micro-sprays, micr0-spinners) applies water or below soil surfaces making it much more efficient in water savings.

III. Sprinkle not more than the earth can receive .
When water application rates (precipitation rates) exceed what the soil can absorb (infiltration rates), runoff occurs.
Use of low precipitation rate heads and proper controller programming helps

IV. Thou shalt not use my water without a plan.
A waterwise irrigation system starts with an irrigation plan that plots head to head coverage.
“ Field engineering” ends up, at best with shoddy coverage and, at worst, hydraulic impotence.
Sub-commandment IV-A: Thou shalt be filled with guilt, if thy give no as-built .

V. Thou shalt not water when I do, nor when I send my winds and tempests. There is a time for every sprinkler under heaven.
Climate should dictate the irrigation schedule.
Use of rain sensors
Use of climate based controllers
On-site weather stations
Off-site weather stations

VI. Water not the sun.
When you water during the day, makes a huge difference in evaporation loss.
Early mornings and early evenings are ideal for sprinkler zones.
Daylight for microirrigation, as its easier to detect problems like cut pipe or blown-out emitters.

VII. Thou shalt not water the fallow field nor the oxcart’s path.
Overspray. Huge quantities of water are wasted .
Relatively simple field adjustments
are usually all it takes.

VIII. Be not slothful in thy maintenance
Irrigation systems are not forever.
Drip filters and emitters get clogged, nozzles plug, heads become misaligned.
The most water-wise design and install is only as good as the future maintenance of it.

IX. Thou shalt know what thy water, when thy water and where thy water. For, verily, I give this gift unto you and thou shalt not be profligate with it.
Timing is everything (or just about) in irrigation
Therefore proper clock programming is paramount.
Proper controller programming in part is based upon how even the coverage is (distribution uniformity –DU)
Water auditing is the process of evaluating DU and deriving a base clock program.

Recommended Resources
Book – “When the Rivers Run Dry”, Fred Pearce
Book – “Unquenchable”, Robert Glennon
Book – “Dam Nation: Dispatches from the Water Underground
Book, VHS, YouTube – “Cadillac Desert, Marc Reisner
DVD, YouTube – “Blue Gold:World Water Wars”
DVD – “The Oregon Story: Water”

Water wisdom for landscape designers

by oldmahon on Jan 26, 2012

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Water wisdom for landscape designers — Presentation Transcript