AHCIRG426A
Evaluate water supply for irrigation

This Unit of Competency specifies the outcomes required to evaluate a water supply for an irrigation operation and defines the standard required to: determine the amount required and quality parameters for irrigation water; carry out water sampling and analyse the results; compare costing and delivery arrangements for alternative water sources; and complete purchasing arrangements.

Application

This Unit applies to irrigation operations managers who are responsible for sourcing irrigation water and analysing its suitability and cost.


Prerequisites

Not applicable.


Elements and Performance Criteria

ELEMENT

PERFORMANCE CRITERIA

1 Determine water needs for irrigation

1.1 The water needs of plants to be irrigated are determined

1.2 The permeability of the soil and deep drainage losses are calculated

1.3 Evapotranspiration rates are calculated through the growing season

1.4 Soil water deficits throughout the season are calculated based on expected rainfall

1.5 The amount of irrigation water required through the growing season is calculated

2 Assess a water source for water quality

2.1 Water source is tested for electrical conductivity and results analysed

2.2 Water source is tested for ionic composition and results analysed

2.3 Water source is tested for biological composition and results analysed

3 Determine cost and availability of alternative water sources

3.1 Water availability and access requirements are evaluated for water sources

3.2 Capital expenditure requirements are costed for water sources

3.3 Operating expenditure requirements are costed for water sources

3.4 Regulatory requirements for purchasing irrigation water are investigated and incorporated into business planning

4 Complete water sourcing and/or acquisition arrangements

4.1 Contractual arrangements are made for purchase or sourcing of water

4.2 Planning is carried out for short term purchasing or selling of water depending on seasonal conditions if necessary

Required Skills

Required skills include:

Ability to:

apply basic principles of hydraulics to the selection of irrigation systems, legal access and structures

take water samples

analyse results for electrical conductivity and ionic composition of irrigation water

estimate the irrigation requirements of plants

calculate water losses in an irrigation system

compare costs for different water sources

calculate capital and operating expenditure for a water supply system

carry out purchasing of water rights.

Required knowledge includes:

Knowledge of:

plant water requirements in terms of water quality and frequency of supply

types of irrigation systems

selection of irrigation systems

irrigation drainage, seepage, surface and subsurface drainage systems

salinity and ionic composition impacts on soil structure and plant growth

conveyance and disposal of drained effluent

re-use systems, management of irrigation systems

operations and maintenance requirements.

water supply potential for the development of irrigation systems

management planning and operation of water allocations

water law

cost benefit analysis

capital and operating expenditure calculations to source water

environmental and energy-use implications of resource utilisation and development

efficiency of irrigation systems and long-term viability

climatic factors in irrigation development, rainfall, evaporation, evapotranspiration and hydrology

plant physiology and plant water use, transpiration crop water requirements in terms of water quality and quantity

soils and water, soil moisture retention and movement, plant root zones and development, infiltration and leaching

irrigation scheduling, soil moisture measurement.

Evidence Required

The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria, required skills and knowledge, range statement and the Assessment Guidelines for the Training Package.

Overview of assessment

Critical aspects for assessment and evidence required to demonstrate competency in this Unit

The evidence required to demonstrate competency in this Unit must be relevant to workplace operations and satisfy holistically all of the requirements of the performance criteria and required skills and knowledge and include achievement of the following:

determine the amount required and quality parameters for irrigation water

carry out water sampling and analyse the results

compare costing and delivery arrangements for alternative water sources

complete purchasing arrangements.

Context of and specific resources for assessment

Competency requires the application of work practices under work conditions. Selection and use of resources for some worksites may differ due to the regional or enterprise circumstances.


Range Statement

The range statement relates to the Unit of Competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording, if used in the performance criteria, is detailed below. Essential operating conditions that may be present with training and assessment (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) may also be included.

Water sources may include:

town water

permanent watercourses

storages

underground water

recycled water.


Sectors

Irrigation


Employability Skills

This Unit contains employability skills.


Licensing Information

Not applicable.