getting it right! drip irrigation, plant selection, and ...ccag-eh.ucanr.edu/files/255377.pdf ·...

Getting it Right! Drip Irrigation, Plant Selection, and Lowering Water Use

CLCA Landscape Industry Show Feb. 1, 2017

Chuck Ingels

Farm & Horticulture Advisor

UC Cooperative Extension, Sacramento County

http://ccag-eh.ucanr.edu

Special Thanks to: Dave Fujino, Loren Oki, and Lori Palmquist

http://ccag-eh.ucanr.edu/




Topics to be Covered

• Drip Tubing and Line Source Irrigation

• WUCOLS IV for Plant Water Use

• Calculating Run Times and Irrigation Frequency

• Lessons Learned with Sprinkler to Drip Retrofit

Tubing Snaked to Plants Inefficient After Year 1

Tubing and Emitters

Standard tubing 18 mm (0.700”)

In-line emitter tubing (line source) 17 mm (.670”)

Tubing and Emitters

Standard tubing 18 mm (0.700”)

In-line emitter tubing (line source) 17 mm (.670”)

Maintenance issues acknowledged!

Standard 17 mm Barbed Fittings

Rainbird Fittings and Insertion Tool Compression

Locking

Universal Compression Fitting (Rainbird)

Fits .620" to .710" (16-18 mm)

Ream out smaller tubing

• Occasional disconnection issues over time

• Can avoid using 18 mm for delivery by using blank 17 mm tubing

In-Line Drip Tubing (Line Source)

(e.g., Netafim, Hunter, DIG)

Rainbird In-Line Drip Tubing

In-Line Tubing Vegetable Beds

Shut-off valve

Pulled aside for tilling

Line Source Drip Irrigation (More plants to come!)

Photo: Lori Palmquist

Line Source Drip Irrigation

• Parallel lines, uniformly wet soil

• Pressure compensating emitters molded into the wall of 17mm drip tubing

– Ensures consistent flow

• Emitters available at 12, 18, and 24” spacing

• Tubing available with 1.0 (0.9), 0.6, and 0.4 gph

– 0.9 gph has been the most common

– Very low flow 0.26 gph can also be ordered

Use supply and exhaust header (loop) (e.g., PVC pipes, 1/2” or 5/8” tubing)

From: Hunter Industries

Header to Ensure Adequate Pressure

Create Map!

Supply Header Buried PVC pipe to carry water to drip

lines

PVC Headers to Ensure Adequate Pressure

PVC to drip adapters

½”

¾”

Snaked Tubing Converted to Line Source

Is the ¾” PVC header big enough?

Water Movement in Soil

Sand Loam Clay

Wetted Area

12” spacing 8” spacing • Depends on Run Time • Greater underground

than on surface • 12” x 12” common but

usually not necessary

Soil Wetted Area Soil Type

Emitter Flow Rate (gal/hr) Diameter (ft) Area (ft2)

Sand

0.5

1.0

2.0

2 to 3

3 to 3.5

3.5 to 4

3 to 7

7 to 10

10 to 13 Sandy Loam

0.5

1.0

2.0

3 to 4.5

4.5 to 5

5 to 5.5

7 to 16

16 to 20

20 to 24

Loam

0.5

1.0

2.0

3 to 5

5 to 6

6 to 7

7 to 20

20 to 28

28 to 38 Clay Loam

0.5

1.0

2.0

4 to 6

6 to 7

7 to 8

13 to 28

28 to 38

38 to 50 Clay

0.5

1.0

2.0

5 to 7

7 to 8

8 to 9

20 to 38

38 to 50

50 to 64

Line Source, Max. Tubing Length

• Maximum length depends on emitter spacing and flow rate

• “Line source” (in-line emitters) - Generally:

– Maximum of 200 1-gph emitters from source

– Drip tubing should be no more than 400 ft. total

• Spaghetti tubing – 8 ft. max. length

• If more needed, consider adding another valve

Parallel Lines, Directing Around Stones

Air Relief Valve (Air Vent)

• Prevents “suckage” when system turned off

– Turn off drip water drains out the emitters to lowest point

• Air & dirt sucked in, dirt may clog

• Air gets sucked into ARV instead

• Place at highest point on tubing

• Not needed with built-in check valves

End Closures

Compression hose end plug with cap

Figure 8 end closure

Narrowing Bed and End Cap

End Cap in Box for Flushing

• Insert end cap(s) in drip system

– Use at far end(s) of zone

– Also used to flush system

• Attach & read pressure gauge

• For sloped ground, test at top and bottom

After Installation Verify Adequate Pressure in Drip Lines

Minimum Pressure Required for Drip (At the most distant emitter)

• Standard tubing = 10 psi

• With check valve:

–Netafim Techline CV = 15 psi

–Rain Bird & Hunter = 12 psi

Source: Ewing Irrigation

Retrofitting Sprinkler System to Drip System

• Use existing underground plumbing, ½” risers

• Choose sprinkler heads to convert to drip

• Replace heads with drip retrofit kit

• Cap risers not used, add end caps

• Turn on water to flush lines

• Attach ½” tubing or multi-outlet bubblers

Sprinkler Retrofit One method

Threaded

Slip

Rainbird Spray to Drip Conversion Kit

• Drip adapter (tee or elbow) • Kit with pressure regulator,

screen filter, and cap • Existing body (may come in kit)

Sprinkler System Riser Retrofit Multi-Outlet with ¼” Tubing

Adjustable flow

6 gph 10 gph

Sprinkler System Riser Retrofit Multi-Outlet Manifold for ¼” Tubing

(Orbit) (Agrifim)

(And many other companies)

Sprinkler System Riser Retrofit Multi-Outlet with ¼” Tubing

Tripping hazard!

In-Line and Plug Emitters ¼” Tubing - For pots, small plantings

New Installation ¼” Tubing

(Installation not yet complete) Does not allow for optimal root growth

Avoid This!

Water Use Classification of Landscape Species IV: What is it and How Do I Use it?

Slides by Dave Fujino

Calif. Center for Urban Horticulture

WUCOLS IV

Turf = high water use

Medium water use plants

Low water use plants

Water Conservation Strategy = “hydrozone”

Tree

WUCOLS IV “Key” Points

1. A guide to plant water needs, not a method for estimating them.

2. Review process based on Qualitative Research approach.

3. Plant factors were made by consensus agreement of leading horticultural professionals.

4. Over 3,500 taxonomic plant groups used in Calif. Less than 5% of species have been evaluated through field research.

5. The “PLANT FACTOR” for MWELO water budget calculation shall be from WUCOLS.

“Simplified” Water Budget Equation for MWELO

Max. Applied Water Allowance (MAWA) = (ETo) (0.45 or 0.55) (LA) (0.62) ETo = Reference Evapotranspiration (in./year) LA = Landscaped Area (sq. ft.) 0.55 = ET Adjustment Factor (residential) 0.62 = Conversion factor (to gal.)

Maximum Applied Water Allowance = gallons/year

Est‘d. Total Water Use (ETWU) = ((Eto x PF) – Re) x (LA) x (0.62) / IE ETo = Reference ET data (in.) LA = Landscaped Area (sq. ft.) PF = Plant Factor 0.62 = Conversion factor (to gal.) Re = Effective rainfall (in.) IE = Irrigation Efficiency (depends on irrig. equipment)

Estimated Total Water use = gal./yr.

To be in compliance with MWELO, ETWU must < MAWA.

If not, adjustments to the landscape design or irrigation scheduling are required.

WUCOLS

(ETo) (.62) [(0.7 x LA) + (0.3 x SLA)]

(ETo) (0.62) [(0.7 x LA) + (0.3 x SLA)]

CCUH Role in the WUCOLS Update Process

• Gain DWR & horticultural industry support

• Hire former WUCOLS authors as consultants, Larry

Costello and Katherine Jones

• Six regional meeting process began late 2012 and ended

one year later

• WUCOLS IV plant database live in 2014

WUCOLS IV Sponsors

• Regional Water Authority (Northern California)

• American Society of Landscape Architects (CCASLA)

• Association of Professional Landscape Designers (APLD)

• American Society of Irrigation Consultants (ASIC; north and south)

• Cagwin & Dorward (N. Calif. landscape construction & maintenance)

• California Association of Nurseries and Garden Centers (CANGC)

• California Landscape Contractors Association (CLCA State)

• California Landscape Contractors Association (San Diego Chapter)

• San Diego County Water Authority

• Water Forum

• Glenn Schmidt Landscaping, Inc.

• Department of Water Resources, Water Use Efficiency

• Data collected through a semi-structured group interview process

• Moderated by a group leader

• Emphasis on a specific topic

• Impressions were collected rather than numbers

Qualitative Research Process – Focus Groups

WUCOLS IV Regions

Members Affiliation

Bob Perry B. Perry Assoc.

Bart O'Brien Rancho Santa Ana BG

Ken Kammeyer KK Associates

Pam Pavela Western Municipal Water District

Ron Kammeyer KK Associates

Marilee Kuhlman Comfort Zones Garden Design

Dave Giddens Giddens Irrig. Design

Members Affiliation

Barrie Coate Coate and Associates

Nelda Matheny HortScience

Don Mahoney Strybing Arboretum

Dick Turner Pacific Horticulture

Nevin Smith Suncrest Nursery

Lori Palmquist Irrigation and Design Consultation

James MacNair MacNair & Assoc.

North Central

South Inland

Central Valley Members Affiliation

Lance Walheim L. Walheim Assoc.

Ellen Zagory UCD Arboretum

Karrie Reid UCCE

Cheryl Buckwalter Landscape Liasons

Taylor Lewis Cornflower Farms

Missy Gable CCUH

Members Affiliation Spencer Knight Palm Desert Diane Hollinger Palm Desert Randy Meyers RG Meyers & Nurseries Ray Lopez Ray Lopez and Associates Jeff Place College of the Desert Hudson Hale Horttech Landscape Construction Bob Perry B. Perry Associates

Members Affiliation Paul Redeker Cuyamaca College Megan Allison Mira Costa College Nan Sterman Garden Writer Dave Ehrlinger San Diego BG Jim Bishop SD Hort Soc. David Reed ASLA

South Coastal South Coastal (San Diego)

High/Low Desert

WUCOLS IV Regions

Members Affiliation Randy Baldwin San Marcos Growers Carol Bornstein LA Nat'l History Museum Kathy Musial Huntington BG Don Hodel UC Cooperative Ext. Mike Evans Tree of Life Nursery Kathy Copley Lightfoot Planning Group

Selection Criteria

• Professional diversity: Nursery professionals, landscape contractors & architects, botanical garden/arboreta staff members, consultants, academics

• We selected only the best "plant people" --- crucial to success

• Team size = 6 – 9 reviewers

1. WUCOLS IV website (http://ucanr.edu/sites/WUCOLS)

2. Search by region and city 3. Search:

a. Botanical name b. Common name c. Plant Type d. Water Use

4. Create your own list of “low” water use plants for your city 5. Save to an Excel file

Searchable Database

http://ucanr.edu/sites/WUCOLS)

http://ucanr.edu/sites/WUCOLS)

Categories of Water Needs

Category Abbreviation % of ETo

High H 70–90

Moderate/Medium M 40–60

Low L 10–30

Very Low VL < 10

Percent of ET Required

0 . 0 0

0 . 2 0

0 . 4 0

0 . 6 0

0 . 8 0

1 . 0 0

W

C

More Leaves & Growth High Expectations

Less Leaves & Growth Low Expectations

Turf

Tr-Sh-Gc

Copyright © 2010-2015 D. Shaw and D. Pittenger

Perennials

Adapted from:

Drip Irrigation Determining Distribution Uniformity

and Irrigation Run time

Loren Oki Dept. of Plant Sciences and Dept.

Human Ecology UC Davis

Getting it Right! Drip Irrigation, Plant Selection and Lowering Water Use

Fair Oaks, CA October 4, 2016

Learning Objectives

• Measuring system performance

Determine application uniformity

(Distribution Uniformity, DU)

• Determining how long to irrigate

Calculating run time

• Determining when to irrigate

Calculating irrigation frequency

Calculating Run Time and Irrigation Frequency

• Distribution uniformity

How evenly water is applied

• Run time

Application rate

Wetting depth

Soil water holding (Plant Available Water)

Scheduling multiplier (DU isn’t perfect)

Run time

Irrigation frequency

Landscape and plant coefficients (KL)

Climate (ETo)

• Math is necessary to understand how to

irrigate accurately and comply with

MWELO

Distribution Uniformity

• Discussion focus:

Inline drip tube laid in a parallel pattern

(line source)

Under mulch


From: Netafim


From: Hunter Industries


From: Rain Bird

Credit: Irrigation Association

Landscape Irrigation Auditor

certification program

• Inspect the site

• Tune up the irrigation system

• Test the system

• Measure and calculate performance

• Interpret the information

Distribution Uniformity Site Assessment

From: Netafim

•Close to and far from valve

•Even pattern

•At least 24 containers

Distribution Uniformity Select emitters to measure

From: Netafim

•Dig under emitter

•Label & place container

•500 mL, 16 oz., pint, 2” PVC cap, etc.

•Set container under emitter


From: Netafim

•Turn on valve

•Collect water – Don’t overfill

•Turn off valve, note run time

•Our example will be 6 min


•Measure the volumes in each container

•Measure in mL (milliliters)

•Record the measurements

Photo: B. Baker



Calculating DU • Average of all (AvgT)



• Rank volumes



• Rank volumes

• Average of bottom ¼

(AvgLQ)



• Rank volumes

• Average of bottom ¼

(AvgLQ)

• DU = AvgLQ ÷ AvgT

Target • Minimum 70%

𝐴vgLQ

AvgT

205

229 = 0.89 (89%)