TWDB Inovative Tecnologies for Agriculture - ITA
The Harlingen Irrigation District received a $249,000.00 grant from the Texas Water Development Board under the Innovative Technologies for Agriculture (ITA) program to develop low cost automatic canal gates, low cost canal water level sensors and low cost soil moisture sensors. The project was a two year project which began in October 2008. Below is a list of the tasks associated with the project.
Task 1 - Low Cost Automatic Gates for Irrigation Canals
The control system hardware and software was developed based on readily available electronic and mechanical components. The electronic and hydraulic components of the system were tested at Harlingen Irrigation District’s FMC and modified accordingly, using test software developed for the purpose. Quality assurance and quality control were verified. Five gates were installed in the field and the SCADA system software was modified accordingly. Data were collected on the operation of the gates in regard to number of operation to failure, changes in power required to operate, failure mechanisms, and other applicable measurements. Documentation, including manuals and drawings, were to be prepared and presented at one or more public meetings.
Task 2 - Low Cost Water Level Measurement using RF Telemetry
The proposed water level measurement device was based on RTU/PLC that uses one or more industry standard communication protocol such as MODBUS or DNP. This device was to be used as the automatic gate controller for Task 1 and the field level soil moisture transmitter for Task 3. Quality assurance and quality control were verified. Ten devices were installed in the field and the associated SCADA system software was modified accordingly. Data were collected on the operation of the device in regard to power required to operate, failure mechanisms, and other applicable measurements. Documentation, including manuals and drawings, were to be prepared and presented at one or more public meetings.
Task 3 - Soil Moisture Management using RF Telemetry
There are a number of commercially available soil water sensors based on the resistance, thermal, or dielectric (capacitance) properties of water in soil. These sensors are available either singly or as multi-sensor probes (MSP) that simultaneously measure soil water at a number of depths. A prototype circuit board that can read a number of different sensors, including the SDI-12 protocol, has been developed as part of a funded project at University of Delaware. Software, RF transmission and a graphical touch-screen interface has also been developed. This prototype system was modified to incorporate the RF technology developed for water level measurement in this proposal and adapt it to irrigation methods used within the region. A system was installed and used to monitor soil water content at various depths under typical grower management. The data were displayed on a conveniently located touch-screen display and also made available over the internet so that it can be viewed elsewhere. Feedback was solicited from growers to determine the type and format of information that would be of most benefit to them as they make irrigation decisions.
Additional Information:
- Auto-Gate Draft Report (PDF document)
- Low Cost RTU Draft Report (PDF document)