Irrigation Scheduling

Irrigation Scheduling

10:00 – 10:15: Personal Introductions

10:15 – 10:45: Background

10: 45 – Noon: Gathering the Data

Noon – 12:30: Break

12:30 – 1:30: Using the Data: Simplified Scheduling

1:30 – 2:30: Using the Data: Advanced Scheduling

2:30 – 3:00: Wrap up discussion

Gathering the Data

STEP ONE: Visual inspection of irrigation system

STEP TWO: Catch Can Test

STEP THREE: Calculating DU

STEP FOUR: Calculating Precipitation Rate

STEP FIVE: Summarize your Findings and Recommendations

Gathering the Data

THE GOAL IS TO DETERMINE

- Distribution Uniformity expressed as a percentage- Precipitation Rate in Gallons Per Minute- Crop Type- Evapotranspiration Rate (ET)- Head Spacing- Lateral Spacing- Sprinkler type (full- half- or quarter-arc)- System Pressure

Gathering the Data

TOOL REQUIRED

- Marker flags- 20 or more catch cans- 100’ measuring tape- 200 ml graduated cylinder (PVC)- Funnel (PVC)- Stopwatch- Clipboard, paper, and pencil

Gathering the Data

STEP ONE: Visual inspection of irrigation system

-Locate timer-Locate and flag sprinkler heads-Identify obvious deficiencies

NOTE: If you plan to repair the obvious deficiencies in the near future, delay the catch can test until repairs are complete.

Gathering the Data

STEP TWO: Catch Can Test

- Select a zone and lay out catch cans- Run sprinklers from 5 – 10 minutes- Measure the volume of water in each

catch can

Gathering the Data

STEP TWO: Catch Can Test

- If you have two different sprinkler arcs on the same zone, ensure the sprinkler heads have matched precipitation rates

Gathering the Data

STEP THREE: Calculate Distribution Uniformity

100.

AVERAGE

LQAVGDU LQ

Gathering the Data

STEP FOUR: Calculate Precipitation Rate

CDATR

CVhrinPR avg

net

66.3)/(

Gathering the Data

EXERCISE: Calculate DU and PR

Catch Can 1 = 25ml Catch Can 11 = 11mlCatch Can 2 = 24ml Catch Can 12 = 15mlCatch Can 3 = 26ml Catch Can 13 = 34mlCatch Can 4 = 0ml Catch Can 14 = 48mlCatch Can 5 = 03ml Catch Can 15 = 45mlCatch Can 6 = 26ml Catch Can 16 = 24mlCatch Can 7 = 23ml Catch Can 17 = 23mlCatch Can 8 = 22ml Catch Can 18 = 19mlCatch Can 9 = 17ml Catch Can 19 = 17mlCatch Can 10 = 16ml Catch Can 20 = 08ml

Five minute run time; 5” X 7” catch cans.

Gathering the Data

STEP FIVE: Summarize your findings and recommendations

- Written report for the site tested- Keep copies of sketches & Maps- Scan if possible-Keep electronic copies of data