WHY YOU NEED IRRIGATION

Your lawn and landscaped areas need exact amounts of water at precise intervals for proper development.  Light rains or short downpours are not adequate, because the soil is not soaked deeply enough.  Deep soaking is important because it encourages development of a deep root system.  Deep-rooted plants have a greater supply of water to draw from and are healthier.  Plants watered with light sprinkling develop a shallow root system, resulting in weaker drought prone plant life.

If rain fall is inadequate, the result is:

-  off color or yellow grass

-  thinner grass with weed invasion

-  increased disease and insect damage

-  increased damage from winter injury and other stresses

The home owner has three basic options to deal with inadequate rain fall:

1. Do nothing and gamble that nature will provide enough water at the right times   and amounts to keep their expensive lawn and landscaped areas alive.

2. Commit to dragging hoses and sprinklers around all summer but then who has that much time to dedicate to watering.

3. Install an underground, fully automatic irrigation system.

HOW TO IRRIGATE

The need for irrigation depends mainly on your soil type, weather and localized conditions (i.e. sun, shade, etc.)

The best thing to do is watch your grass for telltale signs of wilting:

-  irregular patches (bluish-green to purple) during the hot part of the day.

- "foot printing" when you walk across your lawn.

The most accurate way to check the need for irrigation is to feel a sample of soil taken with a soil probe or by using a knife to cut out a wedge about 4 inches deep in the ground.

More frequent irrigation is necessary where:

- rainfall is very limited in the summer.

- heavy clay soils prevent irrigating to the full amount at one time, due to soil saturation which results in run off.

The key to irrigating your lawn is to get enough water into the soil to thoroughly soak the root zone.  How can you determine if you are getting the right amount of irrigation for your lawn?

The weekly requirement is about 1 inch for clay soil, 3/4 inch for sandy soils.

IRRIGATION SYSTEMS AN OPERATIONAL REVIEW
(Click on underlined text for definitions)

The two most common types of irrigation applications are:  drip irrigation or pop-up sprinklers for landscaped areas or pop-up sprinklers for lawn areas.

An irrigation system  usually has many zones and begins at the water supply most suitable for irrigation.  The main line transports water from the water supply, through a shut-off valve, a master valve, a quick-coupler, a backflow preventer,   then continues to  zone valves located throughout the irrigated area of your property and finally to the zone.  The controller opens both the master valve and the specified zone valve and the water then flows to the sprinklers: spray heads or rotors.  If the zone valve opens to a drip zone, the water flows through a filter and a pressure regulator to the drip tubing and out emitters. In the event of rain, most  irrigation systems should have a rain sensor which will not allow the irrigation system to operate.

GLOSSARY OF IRRIGATION COMPONENTS

Backflow  Preventer
This component ensures water does not flow from your irrigation system back Preventer into the potable water supply.  The local water authority specifies which type of backflow preventer to use when the irrigation system water supply originates in your home.  Backflow preventers are located as close as possible to the water supply and are installed as required by the manufacturer. 

Controller
This system component is programmed to tell your irrigation system when and how long to irrigate.  When a programmed time begins, the controller uses a low voltage electrical current to open the designated valves.  When the programmed time ends, the electrical current stops and the valves close.  Specific programming procedures are unique to each controller and may be found in the controller operating manual. Controllers are usually located in easily accessible areas to simplify programming and maintenance procedures.

Drip Tube 
This component holds and supplies water to the emitters located on top of your garden soil but below your mulch.  It is woven throughout the planting in your garden beds and held in place with 6-inch staples.

Emitters
These components irrigate your garden beds by dripping water (like a drip in a kitchen sink).  Emitters create a wet spot proportional to the amount of time you run the irrigation system.  They are either molded into the drip tube and/or manually placed for specific applications.

General specifications:
-  drip approximately 1 gallon per hour.
-  emitters are spaced every 18 inches along the tube.
-  deliver sufficient water in approximately 3-4 hours per week.

Filter
This component removes debris and/or silt which clog the irrigation components of lawn and garden irrigation systems.  Two types of filters are used, system and drip tube filters.

1)    A system filter is used when open water or a well supplies the irrigation system. It is located on the main line as close as possible to the water supply.

2)  A drip tube filter is required for most drip tube applications due to the many small emitters in the drip tube.  It is located just after the zone valve at the beginning of the drip tube zone in an accessible underground box.

Filter screens are generally checked and cleaned on an as needed basis depending on the water supply.

Main Line 
This is the lawn and landscape irrigation system's main water pipe.  It originates at the water supply and transports water to the zones located throughout the irrigated area of your property. The main line is generally only pressurized during  system operations.

Pressure Regulator
This component reduces the water pressure in an irrigation system to ensure Regulator against uneven irrigation.  Two types of pressure regulators are used; system pressure and drip tube pressure regulators.

1) A system pressure regulator reduces the water pressure in the main line.  It is required when existing water pressure exceeds the recommended irrigation system water pressure.  A system pressure regulator is located on the main line as close as possible to the water supply.

2) A drip tube pressure regulator reduces the water pressure in the drip tube.  It is used for most drip tube applications to ensure that the proper "drip" rate is achieved.  A drip tube pressure regulator is located just after the zone valve at the beginning of the drip tube zone in an accessible underground box.

Quick - Coupler
This component is the access used to evacuate the water from your irrigation Coupler system for the winter months.  A quick-coupler allows an air compressor hose to be connected to your irrigation system.  Air then runs through the entire irrigation system evacuating all the water that could freeze and cause damage.  The quick-coupler is located in an accessible underground box as close as possible to your water supply.

Rain Sensor
This component measures rainfall and will not allow your irrigation system to operate if the required irrigation has been achieved by nature.  A rain gauge is usually located on your roofline to discourage tampering and allow for accurate rain measurement.

Sprinklers
These components irrigate lawn and bed areas.  When your irrigation system is running, water pressure pushes them above ground, and they emit a spray of water.  When your irrigation system is not running, no water pressure exists, and they return to ground level.  Sprinklers heads are identified as either small or large. Both types have distinct operating parameters which must be kept in mind when programming the irrigation system controller.

General specifications
Spray heads:
- spray in a fixed fan-like pattern
- have a radius of 7-15 feet
- deliver 1 inch of water in approximately 45 minutes

Rotors:
- gear drive sprinklers that spray in a solid stream and slowly rotate
- have a radius of 20-50 feet
- deliver 1 inch of water in approximately 3 hours.

Valves: 
These irrigation components control the flow of water in your irrigation system. Three types of valves are used:  shut-off, master and zone valves.

1) A shut-off valve controls the flow of water in the main line and is used for system maintenance and emergencies.  It is normally open and must be turned manually to close.  A system shut-off valve is located on the main line as close as possible to your water supply.  We mark that valve with a red tag for easy identification.

2) A master valve controls the flow of water in the main line. It is normally closed and requires an electrical current from the controller to open.  When open, water passes through and flows into the main line. A master valve is located on the main line as close as possible to your water supply. This offers a higher level of system redundancy in that two valves must fail to cause a situation in which the system can only be shut down manually.

3) A zone valve controls the flow of water to the lawn and bed irrigation zones. It is normally closed and requires an electrical current from the controller to open. When open, water passes through the valve and flows into the zone.  A zone valve is located in an accessible  underground box where each zone connects to the main line.

Zone
Irrigation systems are divided into zones, or groups, of similar irrigation components (i.e., rotors, spray heads or drip tube).  The number and size of zones are determined by your water supply and property design.  Each zone is run individually by the controller allowing the different areas of your property to be irrigated as their conditions require (i.e., lawn, garden, shade, full sun, etc.).  A zone only has water pressure in it when the irrigation system is running.

HELPFUL HINTS WHEN IRRIGATING

1) Measure the amount of water you apply.  You can measure the amount of water by placing a can under the spray of the water from your irrigation system.  If you are irrigating once a week, you should irrigate long enough to fill the can to a depth that is right for your soil type (1 inch, 3/4 inches).

2) Be sure your irrigation is uniformly applied.  Check your irrigation system  occasionally to make sure the whole lawn is getting adequate coverage.

3) Make sure you are not irrigating too fast.  If water puddles or runs off in certain areas, adjust your controller (see Controller Operating Manual).

4) Beware of special situations.  There are areas in lawns which require special irrigation practices.

Slopes: Irrigate in short cycles to allow water to penetrate the soil. Otherwise, it will drain down the slope. 

Excessive Thatch: Irrigate slowly to allow penetration of thatch, especially if it is very dry.

Newly Seeded Areas: After seeding, irrigate daily to keep the soil surface         moist.  Do not allow seedlings to completely dry out, but also avoid over irrigating and washing the seeds away.  During hot and dry days, you may need to irrigate two or more times a day.

Areas that Dry Out First: Some spots in your lawn will dry out first.  Since they show signs of drought stress first, use them as a guide to how long you should irrigate.  These areas include:

- grass near paved areas (streets, driveways)

- compacted areas (foot traffic, heavy equipment, etc.)

- slopes

- areas with buried gravel, wood, or other materials (especially with new construction).

5) Stay away from watering between the hours of 3 p.m. and 1 a.m. to avoid possible lawn disease problems.

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