IDMP: Why prepare an irrigation and drainage management plan?
Consumers want food at low prices. Markets need producers to meet specifications. Financiers want a return on investment. Water reforms from government policies and regulations means water is less available for irrigation, and may cost more.
How can irrigation managers meet all these demands? NSW DPI recommends that you prepare and use an irrigation and drainage management plan (an IDMP).
We designed the IDMP to help you look at your business clearly. It will show you how to improve your management, and use water more efficiently and effectively.
What is an IDMP?
An IDMP is made up of:
- a written report
- a base map or plan of the enterprise
- several plans, overlays or maps that show different parts of the irrigated enterprise and how they relate.
- Owner’s goals
- Property information, ownership details and location
- Infrastructure, topography and natural features
- Soil, water and climate
- Irrigated cropping enterprises
- Irrigation systems
- Irrigation drainage, recycling and effluent systems
- Plan for action
In preparing an IDMP, the manager can analyse the technologies available to improve water use efficiency and crop production for each component of the irrigated enterprise. This means that any changes needed to achieve best irrigation and drainage management practice can be identified in section 8, 'Plan for action'. This section outlines the key steps for achieving enterprise goals. It should describe operational and maintenance procedures to maximise the benefits of any changes, and monitoring and evaluation processes to aid the continuous improvement cycle.
How the IDMP can help the irrigation manager
It takes time and energy to prepare a management plan, but it can be a help to an irrigation manager in a lot of ways. The manager can use an IDMP to satisfy personal and business goals and to meet market, community and government demands.
Planning a development or re-development
The manager can outline all the factors of an irrigation development in an IDMP. The IDMP can also give a schedule for the new works and management practices.
Getting more from less water
The manager can develop an IDMP to identify how to improve irrigation water use efficiency. This means getting higher yields for every megalitre of water used. If you increase productivity, you can increase returns per megalitre or, by saving water, increase the area that can be irrigated.
Purchasing irrigation water
The Water Management Act 2000 (NSW) means the Department of Infrastructure, Planning and Natural Resources (DIPNR) has to assess a water transfer before issuing a water use licence. (Before 1 July 2003, DIPNR was the Department of Land and Water Conservation, DLWC.)
To get DIPNR approval, irrigation managers need to be able to show how their management practices and technologies minimise impacts on the environment. They can use the assessment of any proposed irrigation activity from their IDMP to help meet this requirement.
For additional information on requirements for water use licences, contact your regional licensing officer.
Adopting best practices for the farm
In preparing an IDMP, the irrigation manager has to analyse:
- how much water the crop rootzone holds
- how quickly the crop uses water from the rootzone
- how long it takes for irrigation to refill the rootzone
- how quickly irrigation gets into the rootzone
Sustaining natural resources
Irrigation managers aim to use water as efficiently as they can, and improve farm productivity. To do this, they must match the irrigation system, crop requirements and management practices to their farm's soil and water resources.
When managers improve their irrigation water use efficiency they also reduce adverse impacts on the environment. Soil salinisation, waterlogging, nutrient pollution, rising groundwater tables, and water quality degradation are some of these impacts.
On-farm actions help achieve the objectives of larger-scale plans, such as the end-of-valley salinity targets set by catchment management boards. Managers need to consider these objectives when preparing their IDMP.
Linking irrigation and drainage management with other farm plans
An IDMP is focussed on irrigation but contains information that can be used or translated into other farm plans. Whole farm property plans and vegetation management plans use the same kind of maps and natural resource assessments.
Meeting environmental requirements
Markets now tend to reward producers who make sure their irrigation system damages the environment as little as possible. These producers get to keep or improve their access to markets and farm returns.
To get these benefits, irrigation managers need to show they are using best practice, and an IDMP will help them do that.
If a market requires an environmental management system, then the manager can use the IDMP as part of it.
Negotiating finance for development
An irrigation manager can use their IDMP when negotiating a commercial loan. By preparing an IDMP, the manager shows the financier a commitment to best practice. The IDMP also spells out in clear terms how to improve irrigated production and reduce investment risk.
Starting points for irrigation and drainage management planning
1. Attend a WaterWise on the farm course
WaterWise on the farm (previously 'Introduction to irrigation management') is a PROfarm course.
2. Talk to an IDMP expert
Discuss the preparation of your IDMP with a local Irrigation Officer from NSW DPI, who can:
- answer your queries
- give advice about local issues
- tell you how much detail you need
- give you a list of consultants who can help.
Irrigation managers often need to purchase expert advice. How much you use consultants in preparing the IDMP depends on your skills and knowledge, the time you have available, and your finances.
Advice you might use when you prepare your IDMP could include:
Farm management advisors: Farm management advisors help managers check the financial and enterprise performance of the farm. They can discuss options to improve farm productivity and viability.
Soil surveyors: Soil surveyors provide advice in a report and site maps based on field investigations and laboratory analysis. The advice shows how to match your irrigation with your soils. It suggests ways to improve soil management for long-term productivity.
Irrigation designers and consultants: Irrigation designers evaluate the performance of an irrigation and drainage system. They prepare designs for new irrigation systems or for re-developing existing systems.
Agronomists and horticulturists: Agronomists and horticulturists provide advice on managing crops, using best practices, matching crops to sites, and improving crop management.
It is up to you how much external expertise you use in preparing your IDMP. Whatever you decide, you must be involved in preparing the plan, because it identifies the irrigation management practices and technologies to achieve your goals, both personal and business.