The measurement of the water level in a canal allows us to know its flow. This information is essential for the correct administration of the water resource. Manual quantification can be replaced by micro controlled systems with an internet connection. Thus, the measurement and recording of water levels in open canals in real time is achieved. The chosen micro controlled system was based on ultrasonic instrumentation with GPRS communication. It had a wide cellular network to achieve an effective connectivity in rural areas, a power system combining solar energy with pollutant free batteries and the capacity to store data. The obtained percentage and average errors were lower than the permissible error specified in the requirements. Consequently, the evaluated measurement system is reliable for the evaluation of canals in a real-world setting.