Michael D. Dukes, Ph.D., P.E.Agricultural & Biological Engineering

Institute of Food and Agricultural Sciences (IFAS)‏

Tampa Bay Regional Water Shortage Management Workshop

Tampa, FL, May 5, 2009

Water Conservation Potential of

Smart Irrigation Controllers

Irrigation is a Standard “Appliance”

Improper Design & Installation: Improper

Coverage

SMART WATER APPLICATION

TECHNOLOGY (SWAT)‏

What is Smart Water Application Technology

(SWAT)?

• SWAT Irrigation technologies designed to

conserve water

• SWAT concept created approx. 2001 by

Irrigation Association (IA) & water purveyors

• Technologies

• Soil moisture sensor (SMS) controllers

• Evapotranspiration (ET) controllers

• Rain sensors (RS)

Smart Water Application Technologies (SWAT)

Irrigation controllers that respond

to conditions in the irrigated

system to automatically adjust to

plant needs

Soil moisture sensor (SMS) controllers

Evapotranspiration (ET) based controllers

Rain sensors (RS)

SMS CONTROLLER TESTING ON

PLOTS

12' × 12'

Research (2004 - 2008)

SMS/ET Controllers 2006-08, Drought

ConditionsSt. Augustinegrass

testing ongoing since

March 2006

72 plots

18 treatments & 4 replicates

A: Rain Sensors

B: Soil Moisture Sensor & ET

ControllersPhoto May 2006, M.L. Shedd

Irrigation Savings Compared to a Time Schedule No Rain Sensor

72

54

59

39

0

10

20

30

40

50

60

70

80

Normal rainfall Dry conditions

Irri

gati

on S

avin

gs

(%)

Gainesville

Citra

SMS TESTING ON COOPERATING

HOMES, PINELLAS CO.

Treatments

• SMS, Current irrigation system without rain sensor

and with a soil moisture sensor controller

• EDU+RS, Current irrigation system with rain

sensor & seasonal run time guidelines

• RS, Current irrigation system with rain sensor

• WOS, Current irrigation system without a

sensor

0

2

4

6

8

10

12

14

16

18

200

10

20

30

40

50

60

70

Nov-06 Feb-07 May-07 Sep-07 Dec-07 Mar-08 Jul-08 Oct-08 Jan-09

Mo

nth

ly E

ffe

ctiv

e P

reci

pit

atio

n (i

nch

es)

Irri

gati

on

Ap

plic

atio

n (i

nch

es)

Effective Rainfall SMS EDU+RS RS WOS

Pinellas County Homes, Irrigation Nov 06 – Dec 08

62a

54a

34b

22c

0

2

4

6

8

10

12

14

16

18

200

10

20

30

40

50

60

70

Nov-06 Feb-07 May-07 Sep-07 Dec-07 Mar-08 Jul-08 Oct-08 Jan-09

Mo

nth

ly E

ffe

ctiv

e P

reci

pit

atio

n (i

nch

es)

Irri

gati

on

Ap

plic

atio

n (i

nch

es)

Effective Rainfall SMS EDU+RS RS WOS

Pinellas County Homes, Irrigation Nov 06 – Dec 08

62a

54a

34b

22c65%

45%

14%

ET CONTROLLER TESTING,

HILLSBOROUGH CO.

ET Controller StudyGCREC Hillsborough County

• Three ET controllers: Weathermatic, Smartline SL800

Toro, Intellisense TIS-612OD

ETwater, Smart Controller 100

• Timeclock with RS

• Reduced timeclock schedule with RS

Residential study in Hillsborough County…

• 38 residential cooperators in Hillsborough Co.

o 21 homes have an ET controller

o 17 homes are a comparison group

• All volunteers are moderate to high water users

But will ET controllers work in the real world?!

Irrigation Savings Potential

0

10

20

30

40

50

60

70

80

Time Clock Adjustment

Rain Sensor Soil Moisture Sensor, plots

Soil Moisture Sensor, homes

ET Controller,

plots

ET Controller,

homes

Irri

gati

on S

avin

gs

(%)

Rainy

DryN

o d

ata

No d

ata

No

da

ta

Next Steps….

• Applying the technology Targeting users with potential savings

Building public awareness

Education of contractors for proper installation

Verification of savings over time

• Apply to reclaim irrigation to stretch increasingly limited supplies

Thank you!

Southwest Florida Water Management District, Pinellas Co. Utilities, Hillsborough Co. Water Dept., Florida Department of Agriculture and Consumer Services, Florida Nursery Growers and Landscape Assoc., Florida Turfgrass Assoc., Florida Sod

Growers Co-op.

mddukes@ufl.eduhttp://irrigation.ifas.ufl.edu