With so many options for drip equipment, figuring out which type best suits your project can be overwhelming. You can simplify the selection process – and separate yourself from the competition – by recognizing a few key factors. We’ll show you some applications that will help make your projects as efficient and environmentally responsible as possible. You’ll gain some valuable insight that will streamline your equipment specification and shed a whole new light on your irrigation projects.
Note: The following catalog of content covered in this webinar is time stamped to allow you to follow along or skip to sections of the video that are relevant to your questions. You can also search for content on this page using the FIND command in your browser (CTRL + F in Windows, Command + F in Mac OS.)
- Water Use Facts
- Drip Irrigation Defined
- History of Drip
- Drip System Components
- Typical Drip Applications
- Factors to Consider
- Types of Drip
- Point Source Applications
- Inline Applications
- Keys & Specs
- Resources & Contact Info
0:00 – 3:31: Intro/TOC
Overview of Shelly and GPH (2:00)
3:32 – 4:34: Water Use Facts
Water and the population (3:32)
- According to the Census Bureau decennial census, the U.S. population is growing by approximately 3.3 million per year.
- The average American uses 100 to 175 gallons of water per day.
- That’s 63,875 gallons per year.
- The Environmental Protection Agency says drip irrigation systems can save ups to 30,000 gallons of water per year, which is about three times what the average landscape consumes.
4:35 – 5:03: Drip Irrigation Defined
- The slow, precise application of water directly to the soil at the root zone of the landscape plant
- Drip provides an optimal amount of water directly to plant roots, maintaining an optimal degree of soil moisture to meet the plant’s evapotranspiration needs.
5:04 – 7:36: History of Drip
- 100 BCE: Ancient China: porous unglazed pots, water seeped through clay – called olas
- 1800s: Porous clay pipe – Middle East
- 1920s: Germans invented perforated pipe
- 1950s: Plastic extrusion and molding
- 1960s: U.S. farmers began to use drip irrigation for crops
- 1980s: Introduced to commercial landscape in U.S.
- 1990s: Pushback in landscape industry
- 2000s: Resurgence, water shortages, more efficient, more education
7:37 – 12:10: Drip System Components
- Backflow preventer to prevent soil, salmonella, bacteria, etc. from being sucked back into the system
- Isolation and control valves to control the flow of water
- Pressure regulator to reduce water pressure and keep it at a constant level
- Filter to clean the water and remove grains of sand, etc.
- Drip tubing that is laid on the ground between plants
- Emitters attached to the drip tubing to regulate how fast the water is released to the soil
- Flush end cap or indicator flush nozzle
Drip zones (9:56):
- Above grade
- In a valve box
Diagram of a drip system (11:37)
12:11 – 13:29: Typical Drip Applications
- Interior scapes
- Malls, hospitals, casinos, airports, hotels
- Severe environments
- High wind, evaporation
13:30 – 24:37: Factors to Consider
- Client parameters
- Project type
- Commercial or residential
- New or existing
- Use what you have, or need additional or upgraded equipment
Special requests or what they envision
Other important factors to consider (14:38):
- Plant spacing and selection
- Land layout
- Climate and weather
- Soil type
- Water quality
Plant selection (14:48)
The plants’ water requirements are the most important factor.
- Local law or ordinance
- Color or seasonal, high maintenance
- Durability and low maintenance
- Does the plant you select do well in the region of your project?
General guidelines (17:00):
- The roots of turf/grasses grow about 1 foot deep.
- Small shrubs and other plants reach 1 to 2 feet deep.
- Taproots of some trees and shrubs may grow more deeply into the soil. Most roots tend to concentrate in the top 2 to 3 feet.
- Watering below the root zone only wastes water.
Plant spacing (17:40):
- Potted grouped
Land layout (19:04)
- What is your elevation across the project?
- Do you have a slope?
- Water pressure loss or gain?
- Easily accessible or not?
We lose pressure when moving up. We gain pressure when moving down.
- High wind
- No wind
- Dry or humid
- Season change and impact
- Climate history and weather trends
Soil type (20:25)
Water infiltration in soil types (20:50):
- Sandy soil
- Water for a longer period of time. Imagine filling a column of water.
- 1 inch of water penetrates about 123 inches.
- Loam soil
- Moderate watering according to the plants’ needs.
- 1 inch of water reaches 7 inches in depth.
- Clay soil
- Water less time: cycle and soak.
- 1 inch of water soaks only 4 to 5 inches in depth.
Other soil considerations (21:50)
- Site analysis of project
- Or retrieve reports from the client or on your own.
- The soils can vary throughout the project.
- Soil amendments may be necessary.
Water quality (22:10)
- Water source
- Domestic, potable and non-potable, reclaimed, well
- Send to lab, testing services (you can even test it yourself if not required), hardness of the water (salt or calcium)
- Important if issues arise later
What to look out for when testing water (24:00):
- High mineral content
- The top 2 culprits are:
- Filtration and/or chemical treatment
24:38 – 29:36: Types of Drip
- Emitters are inserted into the tubing (polyethylene) spaced every 12 or 18 inches.
- Used with fittings, compression, swivel lock, or barbed.
- The tubing has a plastic look and texture and is aka PE.
- Some emitters have a check valves that hold back up to 10 feet of elevation change.
- Toro uses Treflan and Rainbird uses CopperShield to help slow root intrusion.
Point source (26:10)
- Point source is a combination of emitters and tubing used together.
- Different types of emitters: single-outlet, multi-outlet, threaded, barbed, micro-spray, and micro-stream.
- Certain emitters in point source have check valves up to 15 feet of elevation change.
- Typically combined with hose, tubing, and rigid PVC or PE pipe, with fittings compression, swivel lock, insert, micro-tubing, and micro-fittings.
- Rule of thumb: When the distance between plants is greater than 3 feet on center, use point source.
Inline tubing and components (27:04):
- Typical size used in landscape is 17 mm.
- 12-inch spacing at .6 gph or .9 gah – also, 18-inch spacing is available.
- Used with compression, lock, and barbed fittings.
Point source components (27:34):
- Single-outlet, multi-outlet, barbed, or threaded.
- Multi-outlet barbed or threaded.
- Streamers and micro-sprays and bubblers.
Supply tubing for point source (28:40):
- Compatible with compression fittings lock fittings, and insert fittings.
- Usually dealing with 700 x 600 supply, available in micro- or spaghetti tubing.
- Plastic texture, more economical.
- Life: 7 years in UV
Poly vinyl chloride (PVC flex or vinyl)
- Compatible with PVC SCH fittings with solvent weld.
- Usually working with 1/2-inch IPS size, available in micro- or spaghetti tubing.
- More of a rubber texture, more expensive.
- Life 30+ years in UV.
29:37 – 33:12: Point Source Applications
Point source on-grade (29:37):
- Barbed, single-outlet emitters
- Threaded single-outlet emitters
Point source below grade (32:02):
- Threaded emitters
- Rigid PVC schedule 40 pipe layout to a PVC flex riser.
- Bury everything but the emitter.
- Reclaimed color coding.
- Camouflage to blend in with the landscape.
Point source commercial containers (32:55)
33:13 – 35:35: Inline Applications
Inline on-grade (33:13)
Inline below grade (34:36)
35:36 – 39:04: Keys & Specs
Complete the system (35:36)
- Take advantage of available accessories.
- Stakes, indicators, flushes, air relief valves, fittings.
Keys to success (35:53):
- Design with hydrozones.
- Definition: Hydrozoning is the practice of clustering together plants with similar water requirements in an effort to conserve water.
- Know your hydraulics and maintain at least 10 PSI at the last emitter.
- Choose the highest-quality product available for your application.
Study manufacturer specs (37:27):
- Understanding the unique characteristics of each manufacturer’s product that you’re using in your project.
- Example: Operating pressure, threads, fittings, compatibility
Install drip yourself (38:10)
- Ideas are unlimited.
- Trial and error.
- If you have experience installing, it will make the designing of drip that much more relatable, able to communicate with the installer at a different level.
- Most manufacturers’ ideas have come from the irrigation designer or installers.
39:05 – end: Resources & Contact Info
Commercial irrigation resources (39:05):
- WaterSmart Checkup
- Irrigation Association
- United States Golf Association Water Resource Center
- Landscape Irrigation Best Management Practices
- Water Conserving Tips for HOAs and Large Commercial Properties
- Water Use It Wisely
- A Landscaping Guide for Homeowners Associations
- Turf and Landscape Irrigation Best Management Practices
- Best Management Practices for Commercial and Institutional Facilities (EPA)
- CIMIS Urban Resource Book
Shelly Walker contact information:
GPH Irrigation Products
8031 Redwood Ave., Fontana, CA 92336
Phone: +1 866-582-9684
How a check valve works (39:50)
How to determine when to make inline or point source above or below ground (41:25)
What to do differently with reclaimed water (42:20)
Run-through of the Water Use It Wisely plant watering guide linked above (43:30)
Question: Does a 1-GPM emitter tend to clog more easily than a 4-GPH emitter?
Answer: Not at all. However, a 1-GPM bubbler will clog more easily than a 4-GPM bubbler.