Irrigation Savings: Tips for Water Conservation Melissa Baum Haley Michael D. Dukes Agricultural & Biological Engineering University of Florida

Keys in Irrigation Savings Efficiency Uniformity Design Scheduling Equipment Maintenance

What is Irrigation Efficiency? W s is the irrigated water stored in the root zone W d is the water delivered to the area being irrigated

Uniformity of Water Distribution

Uniformity vs. Efficiency Root Zone Soil Below Root Zone

Uniform -- Efficient Non-uniformity (100% uniformity not practical) Adequate irrigation

Non-uniform -- Inefficient Under irrigated

Non-uniform -- Inefficient Over irrigation

Uniform -- Inefficient

Head-to-Head Coverage Important for uniformity Reduces weed invasion

Head-to-Head Coverage Due to water overlap, more uniform depth of distribution occurs

How to Test Uniformity Catch-can Method

Other Design Issues Pipe size Pressure Brand

Zones Landscape zones can be turned off or greatly reduced once established Zone turf areas and bedding separately because of run time differences – precipitation rate Rotor, Spray, and Microirrigation heads zoned separately because of pressure Rotors – 60 psi Spray – 30 psi Micro – <30 psi

Microirrigation Works well in bedded areas Irrigates 50% less area Types: Micro-Spray heads Drip Tubing

Microirrigation

Flow Rate and Precipitation Rate Spray heads 0.1 – 1 gpm = 1.5 – 8 in/hr Rotary heads 1 – 8 gpm = 0.3 – 2 in/hr Microirrigation (Drip) 0.05 – 0.5 gpm = 0.3 – 1.6 in/hr*  * irrigates 50% less area

Effects of Evapotranspiration Irrigate in early morning Irrigate when wind is low Greatly reduce run times during winter when grass is dormant

Average Spring/Summer Run Times (2 times / wk) Spray heads minutes Rotary heads minutes Microirrigation (Drip) minutes Some controllers allow for multiple programs

Rain Sensor – Auto Shutoff Often the controller is set to run automatically No need to water during a rain storm Must be adjusted: how much rain will shut off the system Check that it works

Controller Battery Backup Protects controller settings during power outages Without, the controller resets itself Many reset to water everyday for 10 minutes on every zone

Backflow Prevention Acts as a check valve to prevent water from re-entering system Prevents contamination of the potable drinking water supply Will cause some pressure loss to system

Pressure Regulators Regulates the amount of pressure entering system or zone All homes do not have the same initial water pressure Different zones require different pressures

Maintenance Examine the system: Are the heads adjusted correctly? Are the heads clogged? Are any heads broken? What is being watered? Do the heads rise above grass height, ground cover, and shrubs?

Broken Sprinkler Head

What to Water

Pop-up Height and Risers

Irrigation Systems Must be a system approach All aspects are interrelated Efficiency Uniformity Design Scheduling Equipment Maintenance

Questions?