Monitoring and controlling small irrigation takes

NIWA and its associates offer a complete end-to-end solution for irrigators who need to show compliance with their regional council-administered water consents. The solution is a system for monitoring open-channel irrigation water takes with an optional controlled gate to deliver programmed flow. This technology can improve productivity by removing the hands on requirements of a manual system.

NIWA has designed and trialed a range of systems that enable irrigators to monitor and control the water they are allowed to abstract from rivers and streams for irrigation. These range from basic monitoring-only to a fully automated and telemetered solution, where irrigators can access their system remotely via the Internet, as if they were at the site.

A simple but smart system

The simplest option is monitoring-only. However many clients opt for full automation - with automatic gate control - which reduces the need to carry out manual tasks such as adjusting gates and downloading data.

A typical system is comprised of these interlinked parts:

  • a flow measurement section, a weir/flume fitted with a water sensing structure
  • a system for logging data and optionally, transmitting it
  • an optional inlet gate structure with gate control system.

These can be fitted to many existing turn-outs or integrated with new turn-out structures. 

Different options

In the basic monitoring system, the abstracted flow is measured and recorded by a standalone, non-telemetered instrument such as the Unidata Hydrologger. This option may be sufficient where there is no gate control or when an irrigator is happy to control the flow with a manually-operated gate and periodically download flow data to present to the council. Alternatively an automatic telemetered system with internet access is available.

Here, a control gate automatically adjusts its position to maintain the flow within a user programmed target range. The gate controller receives flow rate information from the flow measurement instrument and compares it with the target. If the flow is lower than the target the controller increases the gate opening to increase the flow and vice versa. The gate controller adjusts the gate to keep the flow on target.

Because the Neon system is Internet-capable it also enables you to see what's going on at the site and lets you make changes to the flow target, without having to go to the site. It allows you to view activity, data and to change flow settings via the Internet, saving time and reducing operational costs. Telemetry of data, between the site and the Neon server, is possible anywhere there's cellular or satellite coverage at the site. 

See what's happening in real time

Neon provides a window on your irrigation monitoring system. You can check it remotely at any time, or change flow targets (for sites with flow control gates), by viewing secure data from your telemetered sites over the internet. And you don't have to do this from your desktop computer. Your Android Smartphone can provide a mobile view of flow and gate control status, wherever there's cellular coverage. If your site has a control gate, you can also use your phone to change the flow.

If 'out-of-range' flows or other malfunctions should occur, with telemetered sites, you can receive programmed alarms via text or email. 

NIWA can also offer a system support contract where we ensure that the system continues to operate correctly. This can include providing spare equipment and software updates, maintenance and calibration checks (gauging) as needed.

NIWA and Aqua Irrigation Ltd have installed a demonstration station at Springvale Creek in Central Otago. The NEON metering module records water level data, converts it into flow and pushes it regularly to the NEON server. You can access this data on the server in real time and look at the flow history.  

Visit the working site: http://neon.niwa.co.nz 

  • Enter:

Username: NIWA.Guest

Password: NIWAGuest

  • At left of screen, click on 'Springvale Creek'.
  • Click on the 'Irrigation Map' tab at top of screen.

Water level, flow rate, battery voltage and gate position are shown in the graphic representation, with data updates every five minutes.

  • Click on the 'Data Channels' tab at top of screen.
  • Under 'Sensor Name' click on 'Flow(RAW)'.
  • At 'Choose 2nd Channel to Compare', click the 'Channel:' menu arrow.
  • Click on 'Target(RAW) - Active'.

You should see the water flow rate (blue trace) tracking the target (red trace), provided there's enough water available.

  • Click on 'Log Off' at top right of screen to log off. 

More information

If you think that one of these systems could satisfy your irrigation consent needs and improve your productivity, we've created a brochure that should provide most of the information you will need.

Find out more about our irrrigation consent solutions (PDF 7.6 MB)

Related articles

For more information on other irrigation systems that NIWA has automated, here are the links to some other Instrument Systems Update articles:

A decade of irrigation automation

Online water the order of the day in new irrigation scheme

A self-cleaning automated irrigation system

Meet the Miniflume

Integrated irrigation eases the load for landowners

Organizations involved in the project

The instrumentation was designed and supplied by the NIWA Instrument Systems group in Christchurch and installed by the NIWA Field team in Alexandra.

The 'drop-in-place' flow structure was designed, supplied and installed by NIWA's associate, Aqua Irrigation Ltd of Alexandra.

Contacts

Jeremy Bulleid - Instrument Systems 
jeremy.bulleid@niwa.co.nz 

Programmed flow at the outlet (Martin Robertson, NIWA)
Testing the flow-measurement equipment at the outlet: The weir on the left is hydraulically coupled to the stilling well (lid off) and water level sensor in the centre. The Neon (mounted on top) converts water level, from the sensor below it, to flow rate. It also provides feedback for the gate controller (not visible) and enables remote access via a cellular network.(Martin Robertson, NIWA)
A solar-powered automatic gate-controlled small scheme intake, showing the NIWA gate controller mounted on the top of the gate frame and the top of the white stilling well tower behind it.(Martin Robertson, NIWA)
Springvale Creek irrigation scheme: In the foreground you can see the targeted flow emerging at the outlet. The mast behind it supports a communications aerial and a solar panel for power. Behind this, on the left, are the structure and instrumentation that measure and transmit the flow. In the background, you can see the top of the intake control gate structure and gate-control enclosure. (Martin Robertson, NIWA)
[NIWA]
Smartphone app screenshot. [NIWA]
Research subject: Instrumentation