CPCPWT3027A - CONNECT IRRIGATION SYSTEMS FROM DRINKABLE WATER SUPPLY
CONSTRUCTION, PLUMBING AND SERVICE
INTEGRATED FRAMEWORK
TRAINING PACKAGE
CPC08
CPCPWT3027A
CONNECT IRRIGATION SYSTEMS FROM DRINKABLE
WATER SUPPLY
LEARNING GUIDE
ACKNOWLEDGEMENTS
National Plumbing Services Training Advisory Group
Plumbing Industry Commission Victoria
© Commonwealth of Australia 2015
Construction and Property Services Industry Skills Council
PO Box 151
Belconnen ACT 2616
Tel: 02 6253 0002
This work is copyright, but permission is given to trainers and teachers to make copies and contextualise the resources for use within their own training organisation or in a workplace where training is being conducted. This permission does not extend to making copies for use outside the immediate training environment for which they are made, or the making of copies for hire or resale to third parties.
This work was first published in 2004 with the assistance of funding provided by the Commonwealth Government through the Australian National Training Authority (ANTA). The2015 publication has been updated to reflect changes to the national units of competency.
The views expressed in this work do not necessarily represent the views of the Commonwealth of Australia or CPSISC. In addition, the Commonwealth of Australia and CPSISC do not give warranty or accept any legal liability in relation to the content of this work.
The website addresses and other contact information provided in this publication were compiled in good faith and were correct at the time of printing.
The updating of these resources was completed by:
National Plumbing and Services Training Advisory Group, with funding and support provided by the Construction and Property Services Industry Skills Council (CPSISC):
This guide was developed in consultation with representatives of the Plumbing Industry by NPSTAG and CPSISC to support the implementation of the CPC08 Construction, Plumbing and Services Training Package.
Contents
Unit Descriptor......
Element......
Performance Criteria......
Safety......
How will I be assessed?......
Are there any pre-requisites?......
What other resources will I need?......
Introduction......
Example......
Properties of water......
Pressure......
Static pressure......
Dynamic pressure (flow pressure)......
Flow rate......
Measuring water flow rates for a domestic irrigation......
Measuring the water flow using a bucket and stop watch......
Example......
Example......
Measuring the water flow using a dynamic flow testing device......
Types of irrigation systems......
Drinkable water supplies and protection measures......
Excavation processes and procedures......
Minimum cover in public areas......
Minimum cover in private property......
Procedures for jointing......
Copper compression joints......
Silver brazed joints......
Polyethylene compression joints......
PVC-U solvent cement joints......
Safety precautions for solvent cement weld procedures......
Test procedures......
Regulations......
Quality assurance......
Plan work activities......
Determining connection requirements......
Determining the connection size and valve size......
Determine the hazard rating......
Cross connection hazard ratings......
System types......
Protection required......
Individual protection......
Zone protection......
Selecting back flow prevention devices......
Backflow prevention devices......
Registered air gap (RAG)......
Registered break tank (RBT)......
Reduced pressure zone device (RPZD)......
Installation requirements for testable backflow prevention devices (RPZD)......
Pressure Vacuum Breaker......
Installation requirements for testable backflow prevention devices (PVB)......
Double check valve (DCV)......
Installation requirements for testable backflow prevention devices (DCV)......
Dual check valve (Dual CV)......
Atmospheric vacuum breaker (AVB)......
Installation requirements for non testable HCVB backflow prevention devices......
Selecting appropriate materials......
Ordering and checking the delivery......
Tools and equipment......
Connect and test the system......
Setting out......
Excavating the site......
Cutting into an existing metallic water service line......
Bonding straps......
Installing the water supply......
Restoring the water supply and testing the system......
Testing the system......
Clean Up......
Re-instating the ground surface......
Tools and equipment......
Worksheet......
Practical application......
Assessment checklist......
© Commonwealth of Australia 2015 1
CPCPWT3027A - CONNECT IRRIGATION SYSTEMS FROM DRINKABLE WATER SUPPLY
What is this resource about?
Welcome to CPCPWT3027A – Connect irrigation systems from drinkable water supply. This resource will help you gain the skills and knowledge necessary to demonstrate competence in this unit.
How do I use this resource?
This resource is divided into four main sections:
- A learning unit, which contains background information on CPCPWT3027A – Connect irrigation system from drinkable water supply
- Worksheets, which prepare you for the practical application
- Practical application, which allows you to experience connecting irrigation systems from drinkable water supply
- Assessment materials, which help you demonstrate competency.
To complete this unit of competence you will need to:
- read the information contained in the learning unit
- complete the worksheets as instructed
- have your answers checked by your trainer or supervisor
- work with your trainer or supervisor to practice connecting irrigation systems from drinkable water supply
- read the assessment checklist together with the assessment sheets
- complete the assessment.
Learning Resources are not intended to be the only source of information nor are they intended to be an exhaustive form of instruction.
Flexible delivery
The Trainer or Supervisor may adapt and deliver this Learning Resource to suit people from diverse backgrounds to meet equity principles and conform to Legislative Policies.
What do I have to do?
To demonstrate competence in this unit you will be required to show the level of skills and knowledge for each of the elements involved in connecting irrigation systems from drinkable water supply:
- Plan work activities
- Determine connection requirements
- Connect and test system
- Clean up.
If you are unsure of the meaning of these elements you should read the performance criteria on the following page.
CPCPWT3027A / Connect irrigation systems from drinking water supplyUnit Descriptor / This unit of competency specifies the outcomes required to connect irrigation and watering systems from a drinking water supply. It does not include the commissioning of backflow prevention devices or arrangements.
Element / Performance Criteria
Elements define the essential outcomes of a unit of competency. / Performance criteria describe the required performance needed to demonstrate achievement of the element. Where bold italicised text is used, further information is detailed in the required skills and knowledge and/or the range statement. Assessment of performance is to be consistent with the evidence guide.
1Prepare for work / 1.1Plans and specifications are obtained
1.2Work health and safety (WHS) andenvironmental requirements associated with connecting irrigation systems from a drinking water supply are adhered to throughout the work
1.3Quality assurance requirements are identified and adhered to according to workplace requirements
1.4Tasks are planned and sequenced in conjunction with others involved in or affected by the work and statutory and regulatory authorities’ requirements
1.5Tools and equipmentfor connecting irrigation systems, including personal protective equipment, are selected and checked for serviceability
1.6Work area is prepared to support efficient connection of irrigation systems from a drinking water supply
2Identify installation requirements / 2.1Connection size and hazard rating are determined from plans, specification, relevant Australian standards and/or site inspection using relevant information
2.2Valve is sized according to plans and specification
2.3Back flow prevention devices are confirmed as being according to hazard rating
2.4Materialsand equipment are identified, ordered and collected according to workplace procedures
2.5Materials and equipment are checked for compliance with relevant Australian standards, docket and order form, and for acceptable condition
2.6Sustainability principles and concepts are observed when preparing for and undertaking work process
3Connect and test system / 3.1Excavation is set out and made according to plans and specifications and undertaken with consideration given to existing structures and services
3.2Service pipe is isolated and cut to accommodate take off branch according to authorities' requirements
3.3Back flow prevention device is fitted according to relevant Australian standards and manufacturer specifications
3.4System is connected and flushed to required standard
3.5Water supply is restored and system tested according to relevant Australian standards
3.6Ground surface is restored
4Clean up / 4.1Work area is cleared and materials disposed of, reused or recycled according to legislation, regulations, codes of practice and job specification
4.2Tools and equipment are cleaned, checked, maintained and stored according to manufacturer recommendations and workplace procedures
4.3Documentation is completed according to workplace requirements
Required knowledge / Required knowledge for this unit is:
- characteristics and application of different pipes and fittings, including fixing and joining techniques and methods
- drinking water supplies and protection measures
- implications of cross connections and air gaps
- job safety analysis (JSA) and safe work method statements (SWMS)
- process of connecting irrigation systems from a drinking water supply
- processes for accessing information and for calculating material requirements
- properties of water, including pressure and flow rates
- relevant statutory requirements related to connecting irrigation systems from a drinking water supply
- SI system of measurement
- Australian standards applicable to the connection
- use of test equipment and procedures
- various types of irrigation systems and types of materials used
- workplace and equipment safety requirements
An up to date version of the ‘Unit Descriptor’ may be located on the Australian Government web site training.gov.au
Safety
Workplace health and safety (WHS) requirements need to be observed in accordance with legislation. Revision of CPCPCM2043A – Carry out WHS requirements, before commencing this unit is advisable. You need to know the WHS laws governing your job.
Revise CPCPCM2043A – Carry out WHS requirements before commencing this unit.
In any work situation you can reduce the risk of injury to yourself and others by using appropriate personal protective equipment (PPE). The types of PPE that you will need include:
- Overalls – used for the protection of the installer when working in different conditions
- Boots – it is recommended that soft soled footwear is worn while working on roofs, as deep grooved footwear pick up small stones and debris that might damage or scratch the roof sheets
- Safety glasses or goggles to protect the eyes from injury when cutting the sheets with a power saw
- Ear plugs or muffs to protect the installer’s hearing form excessive noise
- Dust masks or respirators to protect the user from breathing in dust or fine particles when cutting the sheets with a power saw
- Gloves, for the protection of the installer’s hands when working with different types of pipes, tools and equipment.
How will I be assessed?
Your trainer or supervisor will decide with you how you will be assessed. Your assessment activity may include completion of the participant worksheet and practical task selected by your trainer or supervisor. Your assessment should allow you to demonstrate all the skills and knowledge required to connect irrigation and watering systems from the drinkable water supply.
This unit may be assessed in conjunction with other units of competence. Your trainer or supervisor will tell you if you are to be assessed this way.
Are there any pre-requisites?
Prior to commencing CPCPWT3027A – Connect irrigation system from drinkable water supply you must have successfully completed the following pre-requisites.
- CPCPCM2043A – Carry out WHS requirements
It is also recommended that prior to commencing CPCPWT3027A – Connect irrigation system from drinkable water supply you should have successfully completed the following competencies.
- Nil.
Project work may also group pre-requisite and or co-requisite competencies together to carry out such projects. It is recommended that the following competencies are grouped with this unit of competency:
- Nil.
What other resources will I need?
To assist you the following resources have been suggested and should be available to you to do this competency.
Texts
- AS/NZ3500 – Plumbing and drainage.
- Plumbing code of Australia.
- State and Territory regulations may override this Learning Guide.
Web sites
Video/audio cassettes
Introduction
In this unit you will look at connecting irrigation and watering systems from the drinkable water supply. Whenever a connection is made to a potable water supply the integrity of that potable water supply must be maintained at all times.
Irrigation systems may range from a simple, manually controlled drip system resting on the ground to a computer managed, multi-zoned, pop-up rotor system. Whichever system is installed there is always the distinct possibility of contamination of the water supply happening if the system does not have the correct backflow prevention device installed. Contamination of the water supply can easily happen if a backflow valve has not been installed and the supply water pressure fails during the sprinkler operation period. When the supply pressure fails a negative pressure may form in the supply main. This could suck contaminated water back into the main supply through the sprinkler system.
Example
An example of this may be as follows.
The water supply to a pop-up system installed in a lawn area fails during the operation period. The lawn area has several sprinkler heads installed and one of these has a puddle formed over it when the head is retracted. If the supply failed during operation and a backflow valve has not been installed this water could be sucked back to, and contaminate, the water main supply line. When the water supply is reinstated this contaminated water will be carried downstream. Thus any downstream users will be supplied with ‘dirty’ water. This demonstrates the need for backflow protection on all irrigation systems at all times.
This unit will look at the types of irrigation systems that can be installed and the types of backflow protection required for each system type.
Before you can connect irrigation and watering systems there are several issues that you must know, including:
- properties of water including pressure and flow rates
- various types of irrigation systems and the types of materials used
- drinkable water supplies and protection measures
- excavation processes and procedures
- Test procedures to check for leaks, pressure levels and venting requirements.
Properties of water
If you are using water from a source other than a reticulated main you will need to have the water analysed to determine its suitability for irrigation purposes. The water salinity (salt content) may be too high for the plants you intend to irrigate. Water from a reticulated supply will usually be suitable for irrigation purposes.
Wherever the water supply is from you will need to determine the supply properties of the water. The water supply properties that affect irrigation are as follows.
Pressure
The units of pressure are Pascals (abbreviated to Pa). However a Pascal is very small so the usual pressure units used to measure water pressure are the kilopascal (kPa). One kilopascal (kPa) is equal to 1000 Pascals (Pa).
Other pressure units by manufacturers include the following.
Other pressure units / Conversion factor for KPa.Pounds per square inch (psi) / X 6.89
Bars (b) / X 100
Converting 20 psi to kPa / 20 psi x 6.89 = 138 kPa
Converting 1.38 Bars to kPa / 1.38 Bars x 100 = 138 kPa
Supply water pressure can be measured in two ways:
- static pressure
- dynamic pressure (flow pressure)
Static pressure
This is the pressure available when there is no water flowing. However, this pressure does not indicate there will be enough water flow for the irrigation system.
Dynamic pressure (flow pressure)
This is the pressure available when the water is flowing at the required flow rate. This pressure will indicate if you have enough pressure and water flow combined to supply the irrigation system requirements.
Flow rate
The unit of volume flow rate is cubic metres per second (m3/s). This is a very large volume of water so the usual flow rate unit used is the litre per second (L/s). This unit has been derived from the cubic metre per second as shown below.
One cubic metre per second (m3/s) is equal to 1000 litres per second (L/s).
Other units of flow rate used by irrigation manufacturers include the following.
Other units of flow rate / Conversion factor for I/SCubic metre per hour (m3/h) / ÷ 3.6 = L/s
Litres per minute (l/min) / ÷ 60 = L/s
Table 2
An example of the conversion process.
Converting 7.0 m3/h to L/s / 7.0 m3/h ÷ 3.6 = 1.95 L/sConverting 117 L/min to L/s / 117 L/min ÷ 60 = 1.95 L/s
Measuring water flow rates for a domestic irrigation
If a simple spray system is to be connected to a reticulated water supply, opening a tap and timing how long it takes to fill a bucket is adequate to measure water flow rates.
However, for pumps and systems that require set pressures to operate, you will need to connect a dynamic pressure/flow measuring device which measures the dynamic pressure while you time how long it takes to fill a bucket.
Measuring the water flow using a bucket and stop watch
When you measure the water flow rate using a stop watch and bucket (see figure below) you will have a final reading that tells you how many seconds it takes to fill a bucket that you know holds a set amount of water. The results of this test will need to be converted to litres per second.
Example
You need to determine the water flow rate from the water main at a clients’ property.
1.Select a tap close to the water meter or near to the point you are going to tap the irrigation system into the clients’ water supply.
2.Select a large bucket (25 litres would be best).
3.Open the tap fully.
4.Push the bucket under the tap and start your stop watch at the same time.
5.Stop the timer when the bucket is full but not overflowing.
6.You will have a reading of how many seconds it takes to fill a 25 litre bucket from that tap.
Example
It takes 22 seconds to fill a 25 litre bucket. This must be converted to litres per second.