Irrigation Evaluation Dotty Woodson Extension Program Specialist Water Resources Texas A&M AgriLife Extension Dallas Research and Extension Center.

Irrigation Evaluation

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

Water Issue – Is there Enough?

• Population and development will more than double by 2060

• Most of this growth will go to urban areas

• 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 landscapes must use water as efficiently as possible to be sustainable

• Earth-Kind program will provide the guidance to achieve this goal

Current Situation

• Water usage increases 35 to 70% during the summer

• An Earth-Kind landscape can reduce water uses from 30 to 60%

• Most homeowners over water

• How Often• How Long• Time of Day• Seasonally

Efficient Irrigation

• According to EPA

Inefficient Irrigation Waste Water

How Many GallonsHow Much Money

Saving Money is not the only Incentive

▪ Every time you apply one inch of water to your landscape, you apply 0.623 gallons of water per square foot

• 2,000 square feet X 1 inch X 0.623 = 1246 gallons• Cost of water $190.00/CCF• CCF = 100 cubic feet =748.1 gallons• 1246 gallons/1.66 CCF X $1.90 = $3.15• $3.15 X 36 = $ 113.40

Water Conserving Practice Water Saving

Landscape with low water requiring plants 50 to 60%

Maintain 2 to 4 inches of mulch in planted areas 10%

Utilize irrigation evaluation/checkup to improve efficiency 10 to 30%

Convert spray nozzles to multi-stream nozzles 25 to 30%

Convert spray irrigation to drip irrigation 50%

Harvest rainwater for irrigation 90%

Install/retrofit WaterSense Labeled Smart Controller 20%

Install Rain and Freeze Sensor 10%

Use ‘Cycle and Soak’ irrigation schedule 20%

Aerate lawn and apply ½ inch compost 20%

Potential Water Savings

Efficient Irrigation

• Applies water evenly through landscape

• Applies water to potential root zone

• Over watering• No runoff

Even Distribution of Water

Irrigation System Evaluation vs

Irrigation System Audits

Irrigation Evaluation• Identify problems• Distribution• Precipitation rate• Irrigation schedule

Irrigation Audit• More in-depth• Software available• Certified Irrigation Auditor

– Texas AgriLife School of Irrigation– Irrigation Association

• Identify problems• Distribution• Precipitation rate• Irrigation schedule

Irrigation Evaluation10 to 30% water Saving

• Most irrigation systems are not efficient– 30 to 60% efficient

• Poorly maintained– Leaks, Misaligned heads,

etc– Rain and Freeze senor– Adjust controller each

season

• Out-of-date controller• 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• Improve Water Distribution• Increase Quality of Landscape• Excellent Neighbor Relations• Most Accurate Method to Determine Run Times

Irrigation Evaluation▪ Site Inspection with Homeowner • Run each Zone/Station• Flag each sprinkler• Identify Problems• Catch Can Test• Irrigation Scheduling

– Time and Date– Days of Week– Start Time– Runtime per zone

Most Common Problems• Clogged nozzles• 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• Bad Design• Poor coverage• Water bubbling, dripping or gushing all the time or just during

run time• Runoff occurs before adequate water applied• Area along road, driveway or sidewalk stays too dry

Clogged Nozzle

Pressure too Low/High

Runoff

Overwatering

Catch Can TestTo identify coverage and runtime• Place 5 to 9 catch cans in each

irrigation zone or station.• Run each zone for 5 to 10

minutes To determine run time • 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 Technology20 to 30% water saving

• Replace wasteful spray nozzles with water saving multi-stream nozzles Hunter Industries– MP Rotator

• Toro– Precision

• Rain Bird– Rotary Nozzle

Smart Controllers20% water Savings

ET Controller Moisture Sensor

Convert to Drip Irrigation50% Water Savings

Cycle and Soak20% Water Savings

• 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