Choosing the Right Irrigation Equipment, Scheduling and Audit Requirements · 2017. 6. 30. · Courtesy of Netafim Irrigation. Irrigation scheduling 492.10. Schedules shall be developed,

www.sonomacountywater.org

Kris Loomis CLIA,CID W.A Programs Specialist [email protected]

Choosing the Right Irrigation Equipment, Scheduling and Audit Requirements

MWELO Ordinance Sections Covered

• 492.7 Irrigation Design Plan• 492.10 Irrigation Scheduling• 492.12 Audit, Scheduling and

Analysis• 492.13 Efficiency

492.7 Irrigation Design Plan A to V

Irrigation components and requirements

a) Metersb) Controllersc) PSI Regulators, boosterd) Sensorse) Manual shut off valvesf) Backflow preventiong) Flow sensorsh) Master valvesi) Runoff preventionj) Soil Infiltration ratesk) Hydrozones

l) Minimum efficiencym) ASABE/ICC802-2014n) Operating demands/restrictionso) Mulch = low flowp) Matched precipitation ratesq) Head to head coverager) Swing joints/riser protections) Check valvest) Areas with a dimension <10’u) 24” hardscape setbackv) Slopes and application rates

Landscape Water Meters

• Non-residential • 1000 Sf or greater

• Residential • 5000 Sf or greater

Either provided by waterpurveyor or privately owned

I’m not a meter

Courtesy of Rain Bird

Selection and Installation Considerations

Courtesy of Netafim Irrigation

Choose the correct meter by design flow range & minimal psi loss

Follow manufacturer’s upstream and downstream installation recommendations


Irrigation Controllers

Must utilize data from either • Evapotranspiration Or• Soil moisture sensing And• Non volatile memory

Courtesy of Hunter Industries

Courtesy of Hunter Industries Courtesy of Rain BirdCourtesy of Weathermatic

Courtesy of Toro / Irritrol

Courtesy of Rachio

Pressure Regulation up or down

If water pressure is below or exceeds the recommended psi of the irrigation devices.Too high or too low?

• Excess psi must be addressed by usingeither a set psi or adjustable regulator

• Low psi can be addressedby installing a booster pump



Sensors

• Rain• Freeze• Wind Must be able to suspend or alter irrigation during unfavorable weather conditions




Courtesy of Weathermatic

Courtesy of Toro / Irritro l

Manual Shut-off Valves

Required close to point of connection • Gate• Ball• Butterfly ValveCan you use the valve on your backflow preventer? No!

IN CASE OF EMERGENCY

Backflow Prevention Devices

Refer to applicable local agency code for requirements

Electric anti-siphon

Double Check R.P. Device

Flow Sensors

Have the ability to detect high flow conditions.

• All commercial applications

• Residential over 5000 Sf

• Size by flow range

• Installation considerations


Master Shut-off Valves

A Love-Hate relationship • Required on all systems*• What they do• Why they do it• Problems they solve• Issues they create• How to get around the issues


Courtesy of Weathermatic


Using a quick coupler can be a challenge with master valves

A remote valve controller may be your new best friend


Prevent Runoff

• Run-off• Overspray• Low head drainage• What is a “similar condition”?

Avoid on hardscapes, adjacent property, non irrigated areas, roadways or structures


Courtesy of Hunter Industries Courtesy of WUCOLS

Soil Type and Infiltration Rates

Soil type dictates:• Water holding capacity • Irrigation frequency

Infiltration rate dictates:• How fast to apply water• Maximum zone run time• Number of cycle start times

Don’t bite off more than you can chew!



Hydrozones

Hydrozones need to be irrigated according to their unique needs Considerations• Plant type• Plant factor• Soil type• Microclimate• Irrigation method• Precipitation rates


Irrigation Efficiency 492.13

System must be designed and installed to meet, at minimum, the irrigation efficiency…regarding the Maximum Applied Water Allowance

Considerations Spray Efficiency ≥ .75 Drip Efficiency ≥ .81Choose quality irrigation products that have:• In-head pressure regulation• Matched precipitation rate nozzles• Larger droplet size• Pressure compensating drip emittersIf audit proves otherwise, improvements should be madeCourtesy of Hunter Industries

Courtesy of Netafim

Efficient vs. Inefficient

Inefficient

Efficient

Inefficient Inefficient

Efficient Efficient

Lack of adequate pressure Excessive system pressure

Larger droplet size

American National Standards Institute (ANSI) / American Society of Agricultural and Biological Engineers’/International Code Council (ASABE/ICC)

Quality tested products • .65 Distribution Uniformity Lower Quarter (DULQ) or higher • Search ASABE/ICC 802-2014 on manufacturer's website• Less flexibility on equipment choices…that’s a good thing• Limited knowledge about compliant products

Operating Demands / Restrictions

Operating demand considerations • Pressure fluctuations due to demand • Reclaimed water availability

Restrictions • # of days per week limitations• Watering window limitations

Mulch = Low Flow

The use of low volume irrigation is required to maximize water infiltration in the root zone

• Drip irrigation with online emitters

• Drip irrigation with inline emitter tubing

Matched Precipitation Rates

Sprinkler heads and other emission devices

• Sprinklers…stick with one brand nozzle per zone• Drip Irrigation…use appropriate and consistent flow• Inline …use the same flow rate per outlet per zone

0

4

0 0

MPR

360 Degree = 4 GPM 0

1

1

2

0MPR

90 degree = 1 GPM 90 degree = 1 GPM 180 degree = 2 GPM

Consistent Flow is the Key for MPR

Pressure compensating = more consistent flow

Non-Pressure compensating = less consistent flow


Consistent Grid = Easier Calculations

Calculating precipitation rate and eventually run time can be less complicated when using this method


Head to Head Coverage

• Goal, to achieve the highest distribution uniformity possible• Even Head to head coverage isn’t perfect • Follow manufacturer’s recommendations

No such thing as 100% DU

Poor coverage

Swing Joints or Other Riser Protection




• Static pressure devices need higher psi rated support

• Dynamic pressure devices can use lower psi rated support

• Above ground options

Check Valves / Anti Drain Valves

• Low head drainage• Run-off• Water hammer• Erosion / surface problems• Water loss- guess how much?

Check valves and/or anti drain valves are required where low head drainage may occur. They help prevent


Courtesy of Hunter Industries Courtesy of WUCOLS

Areas Less than 10’ = No Spray

Irregular shaped areas are generally less efficient and are more susceptible to runoff

Short radius nozzles generally have high precipitation rates of 3” per hour +/- which soil infiltration rates can not match.

Here’s why:

What to do?......


Areas Less than 10’ = No Spray

What you can do: • Inline emitter tubing

offers a variety of application rates to better match your soil infiltration rates.

• Unusual size areas can be designed in a more efficient way.

• Using a tubing with a built in check valves helps to prevent low head drainage on slopes.


24” SetbackThese restrictions may be modified if:• The landscape area is

adjacent to permeable surfacing and no runoff occurs.

• The non-permeable surfaces are designed and constructed to drain entirely to landscaping.

• An alternative is specified that must be approved and prevent runoff. Confirmed in audit.

• No overhead irrigation within 24” of any non-permeable surface.

• May include drip, dripline, or other low flow non-spray technology.

• Can be planted or not planted.

• May be mulch, gravel, or other porous material.

Slopes Greater than 25% = Low Application Rate


Precipitation rate too high

Precipitation rate ok

Study manufacturer design guidelines for your soil type. Consider:• Emitter flow • Emitter spacing • Lateral spacing• Slope

Precipitation rate cannot exceed .75 inches per hour


Irrigation scheduling 492.10Schedules shall be developed, managed, and evaluated to utilize the minimum amount of water required to maintain plant health.

Irrigation schedules shall meet the following criteria:

1. Must have automatic irrigation controller.2. Overhead irrigation only between 8:00 pm and 10:00* (unless

weather prevents it) .3. Scheduling should meet ETWU without exceeding MAWA. 4. Continued………..

Irrigation SchedulingIrrigation schedules shall meet the following criteria:

4. Parameters used to set controller shall be developed and submitted for each of the following:

A. Plant establishment period

B. The established landscape

C. Temporarily irrigated areas

Irrigation Scheduling 5. Each irrigation schedule shall consider for each station

all of the following that apply:A. IntervalsB. Run timesC. CyclesD. Amount applied monthlyE. Application rate (PR)F. Root depthG. Plant type H. Soil typeI. Slope factor settingJ. Shade factor settingK. Irrigation uniformity or efficiency setting

Irrigation Scheduling

All things considered:Plant factor, density, microclimate, efficiency, soil type and slope.

How long do you irrigate for ?

Eto(week) x 60 Or What you need x 60PR What you have

Learning how to calculate irrigation run times requires thought, time, a calculator and training.

Irrigation Audit, Irrigation Survey, & Irrigation Water Use Analysis 492.12

a) All irrigation audits must be done by a local agency irrigation auditor or a third party certified landscape irrigation auditor.*

b) In large projects with multiple installations 1 in 7 lots or approximately 15% will satisfy the requirement.

c) For new construction and rehabilitated landscape projects installed after December 1, 2015

1) An irrigation audit report must be completed and turned in with Certificate of Completion that may include but is not limited to:

• Inspection• System tune-up• System test w/ Distribution uniformity• Reporting overspray or runoff• Preparation of an irrigation schedule


C 1) Continued…• Configuring irrigation controller considering the following:

• Precipitation rate

• Soil types

• Plant factors

• Slope

• Exposure

• Any other factors*


2) The local agency shall administer programs that may include, but not be limited to:

• Irrigation water use analysis• “irrigation water use analysis” means an analysis of water use data based

on meter readings and billing data.

• Irrigation audits• “irrigation audit” means an in-depth evaluation of the performance of an

irrigation system conducted by a Certified Landscape Irrigation Auditor. An irrigation audit includes, but is not limited to: inspection, system tune-up, system test with distribution uniformity or emission uniformity, reporting overspray or runoff that causes overland flow, and preparation of an irrigation schedule. The audit must be conducted in a manner consistent with the Irrigation Association's Landscape Irrigation Auditor Certification program or other U.S. Environmental Protection Agency “Watersense” labeled auditing program.

• Irrigation surveys for compliance with the MAWA• “irrigation survey” means an evaluation of an irrigation system that is less

detailed than an irrigation audit. An irrigation survey includes, but is not limited to: inspection, system test, and written recommendations to improve performance of the irrigation system.

Irrigation Efficiency

a) For the purpose of determining Estimated Total Water Used, average efficiency is assumed to be 0.75 for overhead spray devices and 0.81 for drip system devices.

No such thing as 100% DU

The spray assumption of 0.75 or 75% efficient means that it is estimated that 75% of the water applied landed evenly across the intended irrigated area.

The drip assumption of 0.81 or 81% efficient means that it is estimated that 81% of the water applied landed evenly across the intended irrigated area.

www.sonomacountywater.org

Choosing the Right Irrigation Equipment, Scheduling and Audit Requirements

• Kris Loomis CLIA,CID W.A Programs Specialist II

• [email protected]

Documents

Choosing the Right Irrigation Equipment, Scheduling and Audit Requirements · 2017. 6. 30. · Courtesy of Netafim Irrigation. Irrigation scheduling 492.10. Schedules shall be developed,