Wednesday, August 31, 2011

The Science of Irrigation: Efficiency vs. Uniformity

By Melissa Baum-Haley, Ph.D., MWDOC Water Use Efficiency Programs Specialist

When is the last time you observed your sprinkler system running? Observing your sprinkler system in action can help you save water by improving both the irrigation system efficiency and uniformity. This article will explain the difference between efficient irrigation and uniform irrigation – and what you can do to achieve both when you water your lawn and plants.

The terms efficiency and uniformity are often confused when discussing irrigation. It is a common mistake to use them synonymously. Efficiency refers to how much of the water applied to the plants is ultimately used by them, while uniformity refers to how evenly the water is applied. Uniformity is increased with proper landscape coverage. And while an irrigation system can have sufficiently good uniformity, this does not mean that the actual irrigation event is necessarily efficient.

Here’s a little game to test your knowledge. The following illustrations depict four irrigation water application scenarios in the soil. Within the root zone of the plants, indicated as the area below the ground surface and above the line, the water is used beneficially. Below the root zone, below the white line, the water is lost to deep percolation (drainage). Can you tell the difference between the efficient and uniform irrigation?


A) The irrigation water applied is both uniform and efficient (the goal).

B)While efficient in terms of conservative water use, the irrigation was not uniform. Under-watering areas in the root zone will result in plant quality decline (leading to pest and weed invasion, or "dry spots").

C) The common cure the "dry spots" is watering longer. This leads to non-uniformity and inefficiency due to over watering some areas.

D) Uniform but inefficient due to overwatering, resulting in drainage below the root zone (which, with time, can result in plant loss as well as the transport of excess nutrients, fertilizers and pesticides that harm the environment).

So, how does your irrigation system compare? Here’s a simple way to evaluate the uniformity of the irrigation distribution in your own yard. You will need:
• 16-24 empty tuna cans, pet food cans, ramekins, or similar containers for water catchment (note: all catchment containers must be the same size)
• A ruler
• A pad and pen

What to do:
• Evenly distribute the catchment containers around the turfgrass area.
• Draw a map of the catchment container locations.
• Irrigate the turfgrass area as usual.
• Measure and record the depth of water collected in each container.

Results:
• If there is more than a ¼ inch variation of water collected within a certain area of the test site, the distribution of applied irrigation is not uniform.
Want to know more? What you have just measured is the uniformity of how you water your lawn during your regular watering cycle. The lack of even distribution (uniformity) can result from either 1) how the timer is set, or 2) the sprinkler equipment. Let’s dig a little deeper.

• Manually turn on the irrigation system, zone by zone.

• Determine which zone(s) are watering the turfgrass area.

• Note whether the zone(s) are using spray heads, rotor heads, or other.

• Observe the sprinklers as they run.

Spray Head
Rotor Head
Drip Irrigator


Q: Is the area irrigated by more than one type of sprinkler head?

A: Different types of sprinkler heads will apply different amounts of water (referred to as the application rate).

Q: Is the test area irrigated by one, two, or more zones?

A: If the test area is irrigated by multiple zones, the scheduled run time for each zone must be matched. If the zones both have the same equipment type (sprinkler head), try retesting so each zone is set to run for the same length of time (for example, 15 min). If the zones water the area with different types of sprinklers, use this rule of thumb for rerunning the test, set the spray head zone to run for half of the time as the rotor head zone.

Q: Are there any geysers, leaks, or ponding?

A: Broken equipment can result in variations in water pressure within the system. Changes in water pressure will affect the water distribution pattern and system uniformity.

Issues like these reflect both the uniformity of distribution and overall efficiency of the system. Good uniformity combined with proper irrigation scheduling will result in reduced pest and weed invasion and fewer "dry spots".

Remember, even the smartest of irrigation controllers cannot correct for inefficient irrigation design, improper installation, or lack of maintenance. The potential of water savings that result from efficient watering practices must take the irrigation system, landscape design, and maintenance each into consideration. The three fundamental roadblocks for fully achieving the watering efficiency potential when considering the use of irrigation technologies are: (1) how to use the equipment, (2) when and how long to water, and (3) system uniformity. This requires a holistic approach, to realize true water use efficiency potential.

So, we’ve now completed the second lesson in our Science of Irrigation series. In the next installment, we will examine irrigation controllers and explain just what makes a "smart" controller so smart.

For more information about irrigation uniformity and efficiency, please contact Melissa Baum-Haley at (714) 593-5016.

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Greg Sebourn

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My Grandma - A Eulogy

LET'S TALK ABOUT 1914 FOR A MOMENT.



FOR STARTERS, GRANDMA WAS BORN TUESDAY, DECEMBER 22, 1914 IN HER FAMILY'S ATWOOD RANCH HOUSE.



IT IS WORTH NOTING THOSE ALSO BORN IN 1914:

JACK LALANNE

JOE DIMAGGIO

DANNY THOMAS



AND WHO DIED IN 1914:

JOHN MUIR, THE FAMOUS NATURALIST FOR WHICH NUMEROUS ROADS, PARKS, HOTELS, AND NATURE RESERVES ARE NAMED.



IT IS ALSO WORTH NOTING THAT IN 1914 WOODROW WILSON SIGNS MOTHER'S DAY PROCLAMATION AND BABE RUTH MAKES HIS MAJOR LEAGUE DEBUT WITH THE RED SOX. MOTHER'S DAY AND BASEBALL- TWO OF MY FAVORITES!! (PERHAPS HER NICKNAME "BABE" CAME FROM BABE RUTH???)



GRANDMA WAS BORN INTO A PERIOD OF TIME FILLED WITH TURMOIL. IN JUNE OF 1914 ARCHDUKE FRANZS FERDINAND WAS ASSASSINATED. WITHIN ONE MONTH WORLD WAR I RAGED ACROSS EUROPE. TWO DAYS AFTER HER BIRTH HOWEVER, GERMAN AND BRITISH TROOPS INTERRUPTED WWI TO CELEBRATE CHRISTMAS. (PERHAPS THEY PAUSE KNOWING THAT A GREAT WOMAN WAS BORNE) WORLD WAR I CONTINUED UNTIL THE TREATY OF VERSAILLES IN 1919.



ALTHOUGH SHE WAS ONLY 5 YEARS OLD, SHE SAW THE LEAGUE OF NATIONS CREATED AND THE 19TH AMENDMENT WAS APPROVED BY THE U.S. CONGRESS GUARANTEEING THE RIGHTS OF WOMEN TO VOTE.



SHE LIVED THROUGH MANY NOTABLE EVENTS. LIKE THE 1933 LONG BEACH EARTHQUAKE OR WHEN ATWOOD FLOODED ALONG WITH MOST OF ORANGE COUNTY IN 1938 AND THE FLOOD-WATERS CLAIMED MORE THAN 50 PEOPLE, 43 OF WHICH WERE FROM ATWOOD! ALL OF THIS DURING A TIME THAT WE READ ABOUT IN SCHOOL AND KNOWN AS "THE GREAT DEPRESSION". SOMEWHERE IN ALL OF THAT SHE FOUND THE LOVE OF HER LIFE, GRANDPA LEO, GRADUATED HIGH SCHOOL, GOT MARRIED, AND HAD KIDS!



THEN THERE WAS WORLD WAR II. FROM PEARL HARBOR TO HIROSHIMA, GRANDMA WAS RAISING MY UNCLE BOB AND MOM ARLINE. WITH AIR-RAID SIRENS AND BLACKOUTS SHE WAS A WIFE AND MOTHER. WHAT A TIME TO RAISE CHILDREN! I BET GRANDMA'S PARENTS WERE ABEL TO TELL HER A THING OR TWO ABOUT RAISING KIDS IN WARTIME.



GRANDMA WAS THERE WHEN THE BOY SCOUTS OF AMERICA HELD THEIR 3RD ANNUAL NATIONAL JAMBOREE IN 1953. SHE SAW AIRBASES OPEN IN '42 AND CLOSE IN '99. SHE WATCHED WALTER KNOTT START UP HIS BERRY FARM AND WALT DISNEY TURN ORANGE GROVES AND STRAWBERRY PATCHES INTO DISNEYLAND!



SHE SAW THE HORSE AND CARRIAGE FADE AWAY INTO HISTORY AND SPACE TRAVEL EXPLODE BEFORE HER WITH THE FIRST LUNAR LANDING. JUST IMAGINE HOW MUCH TECHNOLOGY HAS CHANGED OVER THE LAST 100 YEARS. FROM TUBE RECTIFIERS TO SUPERCONDUCTORS; FROM TRANS-ATLANTIC TELEGRAPH CABLES TO SATELLITE TV.



SHE SAW MORE IN HER 93 YEARS THAN MOST OF US WILL EVER READ ABOUT, LET ALONE LIVE THROUGH!



OF THOSE 93 YEARS IT IS MY HONOR TO HAVE BEEN HER GRANDSON FOR 35 OF THEM. SHE WAS MY MOTHER WHEN MOM HAD TO WORK. SHE WIPED MY NOSE AND PUT FOOD IN MY MOUTH. SHE LET ME PLAY WITH GRANDPA EVEN THOUGH SHE NEEDED HIM TO TAKE HER TO THE STORE. SHE WAS MY GRANDMA AND I WILL MISS HER IMMENSELY.



JUST LOOK AROUND THIS ROOM; SHE DID THIS. SHE IS RESPONSIBLE FOR BRINGING SO MANY GOOD PEOPLE INTO THIS WORLD AND TOGETHER TODAY. THIS IS HER LEGACY.



A Dedication To My Loving Wife, Stacey. Thank you for all you do for me!

Brad Paisley - I Thought I Loved You Then


I remember trying not to stare the night that I first met you
You had me mesmerized
3 weeks later in the front porch light taking 45 min to kiss you goodnight
I hadn’t told you yet but I thought I loved you then

Chorus
Now you’re my whole life now you’re my whole world
I just can’t believe the way I feel about you girl
Like a river meets the sea
Stronger than it’s ever been
We’ve come so far since that day
And I thought I loved you then.

I remember taking you back to right where I first met you
You were so surprised
There were people around
But I didn’t care I got down on one knee right there
And once again I thought I loved you then

Chorus
Now you’re my whole life now you’re my whole world
I just can’t believe the way I feel about you girl
Like a river meets the sea
Stronger than it’s ever been
We’ve come so far since that day
And I thought I loved you then.

I can just see you with a baby on the way
I can just see you when your hair is turning gray
What I can’t see is how I’m ever gonna love you more
But I’ve said that before.

Now you’re my whole life now you’re my whole world
I just can’t believe the way I feel about you girl
Well look back some day at this moment that we’re in
And I'll look at you and say I thought I loved you then
And I thought I loved you then...

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