Irrigation Evaluation

Dotty WoodsonExtension Program SpecialistWater ResourcesTexas A&M AgriLife ExtensionDallas Research and Extension Center

Water Issue – Is there Enough?

• Population and development will double by 2060

• New water resources will cost billions of dollars

• Conservation is the easiest and least expensive way to make our water resources sustainable

Efficient Irrigation

• Future sustainable landscapes must use water as efficiently as possible

Current Situation

• Water usage increases 35 to 70% during the summer

How Many Gallons

• One acre = 43,560 square feet▪ One-acre feet of water = 26,136 gallons▪ Every time you apply one inch of water to your

landscape, you apply 0.623 gallons of water per square foot

• 1/5 acre = 8,712 square feet• 8,712 x 0.6 = 5,227 gallons• 5,227 x 16 irrigations = 83,632 gallons

• How Often• How Long• When• Seasonally

Efficient Irrigation

Efficient Irrigation

Even Distribution of Water

Irrigation System Evaluation vs

Irrigation System Audits

There is a difference

Irrigation Evaluation• Most irrigation systems are

not efficient– 60% or less

• Poorly maintained– Leaks, Misaligned heads, etc– Rain and Freeze senor– Adjust controller each season

• Conserve water• Save money

Irrigation EvaluationPurpose:• Check Irrigation Efficiency• Create an Efficient Irrigation Schedule • Identify Problems with Irrigation System• Potential Water Savings• Potential Dollar Savings• Improved Water Distribution• Increased Quality of Landscape• Excellent Neighbor Relations• Most Accurate Method to Determine Run Times

Irrigation Evaluation▪ Site Inspection with Home or Business

Owner/Representative • Run each Zone/Station• Identify Problems▪ Irrigation Scheduling • Irrigation frequency • Run times per zone

Most Common Problems• Clogged nozzle• Misaligned heads• Misdirected heads• Mismatched heads• Leaking or Broken pipes/heads/valves• Too high or too low water pressure• Irrigation head too low• Grass too high• Tree, shrubs, groundcover grown to block irrigation• Poor Design• Dry landscape areas or poor coverage• Water bubbling, dripping or gushing all the time • Runoff occurs before adequate water applied• Area along road, driveway or sidewalk stays too dry

Catch Can Test• Place 5 to 9 catch cans (tuna or cat

food cans work great) in each irrigation zone or station.

• Run each zone for 3 minutes To determine run time (time each station should run)

• Some irrigation systems apply water faster than the ground will absorb 1 inch of the water so water run off. To this, you may need to run these stations several short times instead of one long time.

• If the water level in each catch can varies greatly, go through the Irrigation Check to help identify problems

• Test each zone. Water application and distribution can vary by zone.

New Irrigation TechnologySaves Water

• Replace wasteful spray nozzles with water saving multi-stream nozzles

• Hunter Industries– MP Rotator

• Toro– Precision

• Rain Bird– Rotary Nozzle

Soak and Cycle• Determine how long to run each

zone (see ‘Catch Can Test’)• Water these areas in 2 or 3 short

cycles or 4 cycles if on a slope instead of 1 long cycle.

• Wait 20 to 30 minutes between cycles.

• Most irrigation controllers have a way to set different start times. If you have trouble programing your controller, visit the irrigation controller company’s web site or contact their customer service for instructions.

• Some newer controllers have a soak and cycle settings, so this may be a good time to upgrade your irrigation controller.

Resources• http://irrigation.tamu.edu/• http://aggie-horticulture.tamu.edu/• http://texaset.tamu.edu/• http://turf.tamu.edu/• http://rainwaterharvesting.tamu.edu/• http://dallas.tamu.edu/

For More InformationDotty WoodsonExtension Program Specialist- Water ResourcesBiological and Agricultural Engineering DepartmentTexas A&M AgriLife Extension17360 Coit RoadDallas, Texas 75252972-952-9688D-woodson@tamu.edu