With the aim of becoming a smart and sustainable city, Marseilles has become equipped with what is known as a “smart” irrigation device. This tool represents the city’s green response to improving its services and offering its users more green spaces of quality.
This new device,stemming from the common ambition of the Parks and Gardens department and the Public Information Office (DSI), is being deployed during a first phase on the iconic site of the Old Chapel (plages de la Vieille Chapelle), which will host some of the events of the 2024 Olympic Games.
The city has set itself the following aims and ambitions:
• Being in a position to manage “remotely” adjustments to the irrigation programming
• Watering precisely to promote root development and the continued existence of the plant, while saving on water.
• Map the water supply and plant growth patterns so as to be able to manage them better.
• Detect leakages and anomalies in the water supply system as early as possible.
The full scope of the project led by the city of Marseille is unprecedented in France; it covers the automatic control of the irrigation vis-à-vis the soil water reserve, the mapping of the water resources, detecting leakages and other anomalies and monitoring tree recovery. After taking a look at the main players in the market, it decided to test it by issuing a call to tender so as to be able to offer a wide range of solutions. The City’s Department of Information systems (DSI) played a key role from the very beginning, so as to bring this initiative in line with the ambitions of a smart city.
The organisation Greencityzen was selected, a company providing ground-breaking innovative solutions in the field of irrigation.
Irrigation is now adapted to the needs of the plants, via connected sensors
Up till then, the city had used an automatic wired irrigation system, such as the one used in most green spaces. It is programmed at the beginning of the season and irrigates in accordance with a schedule set in advance without the capacity to adjust automatically and be able to cope with climate change.
The new device, based on the IoT (Internet of Things) technology, captures key data from the surroundings: measuring the available soil water reserve, the pressure in the pipes, weather parameters, root development, water consumption. Algorithms are applied to the data in a way that enables daily irrigation to be adapted.
The solenoid valves only trigger the irrigation when the available soil water reserve is insufficient for the plants. The irrigation strategy can also be adapted to cope with heat waves and hot weather.
All of this results in very significant savings on water (60%) and a reduction in the number of trips to the site made by the agents and thus the monitoring and maintenance operations are carbon-free.
More efficient tools available for managing the plant and operating the water supply system
To be able to manage these green spaces properly, the agents had to travel to the sites on a regular basis in order to monitor the plants or water supply system, check for leakages or broken sprinklers… In spite of making all these trips, it was impossible to detect the hidden leaks or identify the falls in pressure that are damaging to the plant.
This is the second major contribution of the selected solution: being in a position to supervise the whole project, with alerts available, thus allowing the manager to go to the correct site, at the right time and with the suitable tools of intervention.
An approach that meets the challenges posed by a smart and sustainable city
The challenges facing the Marseille IT Department are sovereignty and interoperability, i.e. having full control over the data collected and technological choices in the future.
From the outset, Marseille’s IT department specified that open and interoperable technologies will be implemented for this project. For example, an interoperable IoT solution can make water consumption data available to the city’s flow management information system. It can also allow the city to change sensor suppliers whenever a contract is renewed.
There was an obvious need from the beginning to use Lorawan technology, standardized on all the protocol layers of the stack in order to meet these challenges.