Landscape Irrigation System Evaluation and Management

1. Landscape IrrigationSystem Evaluation and Management May 17, 2014 Mendocino College Paul Zellman

2. Landscape IrrigationOverview • Goal of good irrigation management: • Supply plant materials the: • correct amount of water, • at the proper time. • Maintain irrigation systems for peak performance • Make careful decisions on when and how much to irrigate. Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

3. Efficient Irrigation Water Management • Quality Hardware: • design, • installation. • Vigilant Maintenance: • regular monitoring (weekly, bi-weekly, ???) • timely repairs • Weather-based Irrigation Schedules • Controllers updated weekly based on local weather. Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

4. Effective Landscape Irrigation • Irrigation systems should be designed, installed, and maintained to distribute water as uniformly as possible. • Irrigation system should be operated long enough to apply a depth of water equal to the water use of the landscape plus extra to compensate for the non-uniformity of the system. • The irrigation system should be designed, maintained, and operated to avoid runoff. Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

5. Steps to Develop a Landscape Irrigation Schedule • Walk-through Inspection & make necessary repairs (Weekly?) • Precipitation Rate (PR) & Distribution Uniformity (DU) • Understand the Water Needs of your landscape plant • Calculate station Run Times to meet the water needs of the landscape. • Decide the Frequency of Irrigation and if "cycling" is necessary • Verify the irrigation schedule with field observations and adjust if necessary. Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

6. Step 1. Walk-through Inspection BTW – I love my Hunter remote control. 20% to 50% of water savings is found here Broken parts & plant growth blocking water spray Irrigation Hardware Controller, wiring, valves, rainfall & soil sensors, pressure regulators Soils - ponding, thatch, compaction Physical Problems Broken components, Heads / Nozzles mismatched, uneven spacing Wrong spray pattern, sunken heads, worn nozzles, unequal pressures, heads not vertical / perpendicular to slope, clogged, not turning, low-head drainage. Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

7. Step 1. Walk-throught Inspection Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

8. Step 1. Walk-through Inspection Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

9. Step 2. IrrigationSystemPrecipitationRatesand DistributionUniformity Once the "walk-through" inspection is completed and the necessary repairshave been made, Performance of the system can be evaluated *Precipitation Rate (PR) *Distribution Uniformity (DU). GPM x 96.3 PR (In/Hr) = ──────────────────────── Landscape Area in square feet Average of the Low Quarter DU = ──────────────────────── Average of AllMeasurements Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

10. Step 2. Catch Can – PR & DU Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

11. Step 2. Catch Can: PR & DU Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

12. Step 2. IrrigationSystem PR & DU Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

13. Step 2. IrrigationSystem PR & DU Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

14. Step 3. Water Needsof Turfgrasses ETo x Kc = Plant ET Turfgrasses Crop coefficients (Kc): cool-season 0.80 (0.60)vs. & warm- season 0.60 (.35) Cool season: tall fescue, ryegrass, bentgrass, and Kentucky bluegrass. Warm season: bermudagrass, zoysiagrass, buffalo and St. Augustinegrass. **Save 25% of water by using warm season grasses (*winter brown => over seed) Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

15. Step 3. Water Needsof Turfgrassand LandscapePlantMaterials Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

16. Step 3. Water Needsof LandscapePlantMaterials Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

17. Steps to Develop a Landscape Irrigation Schedule on your Irrigation Controller • Setcontroller Date and Time • Set Stations with Programs to match Plant Water Needs Groupings: e.g. Program A = Turf; B = Shrubs – North; C = Shrubs – South; D = Deck Pots. • Set Days of Week to Irrigate, e.g. once per week or daily (pots vs. turf) • Set Run Times to meet the water needs of the landscape. • Set Start Times: If runoff occurs, set two or more run times. Station Runtime (minutes per week) = Days per week X Run Time X Start Times Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

18. Step 4. CalculateStationRun Times StationRun Times Individual station run times are determined from both plant water use estimates (ET) and the system PR and DU on a daily, weekly, or monthly basis: 1) The Precipitation Rate (PR) of the irrigation system in inches/hour. 2) The Distribution Uniformity (DU) of the irrigation system. The DU is used as an estimate of the irrigation efficiency (IE). DU will account for the losses due to non-uniformity of irrigation. IE accounts for uniformity, runoff, and deep percolation losses. 3) Historical or Real Time Evapotranspiration (ETo) Information. 4) Crop Coefficient (Kc) Values: ETo x Kc x 60 RUN TIME (minutes) = ────────────────── PR x DU Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

19. Step 5. Frequency of Irrigation: is “cycling” necessary? Is there surface water runoff with calculated runtimes? If yes: you must schedule two or more runtimes. Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

20. Step 6. Verifythatyourschedulemeetsyourplantneeds. Ifnot, adjustrun times. *** Use youcontrolleradjustmentfeature:“SeasonalAdjustment”, “ETo”, etc..How are yourplantsdoing? Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

21. Step 7. Relax.Thisisnotrocketscience.TheRussianRiverFlood Control Districtisnotouttogetyou…perhapsyourneighbor... Paul Zellman paulzellman.com Vineyard and LandscapeConsulting

22. Reference Materials and Sources of InformationIrrigationScheduling - Publication 21454Basic Irrigation Scheduling - Leaflet 21199Turfgrass Water Conservation - Publication 21405Reference Evapotranspiration for California - Bulletin 1922Determining Daily Reference Evapotranspiration - Leaflet 21426Using Reference Evapotranspiration and Crop Coefficients to Estimate CropEvapotranspiration: Agronomic Crops, Grasses and Vegetable Crops - Leaflet 21427Trees and Vines - Leaflet 21428Turfgrass Irrigation Scheduling - Leaflet 21492EvaluatingTurfgrassSprinklerIrrigationSystems - Leaflet # 21503Farm Irrigation System Evaluation: A Guide for Management.1978. J.L. Meriam and J. Keller.Landscape Water Management Handbook. DWR Office of Water Conservation. 1987.R.E. Walker and G.J. KahUniversityof California Sites:Dr. Richard Snyder’s U. C. Davis weather and irrigation scheduling information site:http://biomet.ucdavis.edu/index.phpDennis Pittenger’s U.C. Riverside web page withlandscapemanagementinformation:http://plantbiology.ucr.edu/coop.html (scrollto “Dennis Pittenger” link). Paul Zellman paulzellman.com Vineyard and LandscapeConsulting