The Terrassa City Council, together with Lafcarr Project & Design, has installed a system of sensors and automatic barriers in the Palau stream. These will be activated in the event of a sudden rise in water level. This mechanism aims to reduce the risk for users during flooding events, as the barriers will prevent crossing the stream at designated points.
The Mayor of Terrassa, Jordi Ballart, accompanied by the Deputy Mayor for Territory and Sustainability, Lluïsa Melgares, the Councilor for Streams, Jennifer Ramírez, and the Councilor for Civil Protection, Xavier F. Rivero, visited the new sensor and automatic barrier system installed at the intersections of Camí dels Horts and Carena de Mas Bellver with the Palau stream.
Ballart emphasized that “this system allows us to control access to the area and protect people in potentially dangerous situations caused by sudden water surges during heavy rain periods. Now, thanks to this system of automatic barriers, traffic can be cut off at these crossings either automatically or remotely.” The mayor also noted that “having a safety system in these locations, where in the city’s history we have unfortunately seen accidents or loss of life, has been and remains a key concern for the City Government.”
Two Level Sensors and Four Barriers
The project, with a cost of €33,457.83, involved the installation of an ultrasonic level sensor located at the intersection of Edison Street and Joaquim Sagrera Avenue. It measures the water level in real time and is programmed to trigger an alert when the level reaches 0.70 meters. Another ultrasonic level sensor has been installed on Carena de Mas Bellver Street, which will activate an alert when the water level reaches 1.65 meters.
Four automatic barriers have been installed at two intersections of the Palau stream, specifically on Carena de Mas Bellver and dels Horts streets—areas where water can overflow during flooding and pose a risk to traffic. Barriers are placed at each end of the stream crossings to prevent vehicles and pedestrians from entering during risk situations. Each is equipped with LED signaling systems that provide visual alerts during the raising and lowering of the barriers.
Ultrasonic Sensors
The ultrasonic sensor on Edison Street operates with an electric power supply, while the barriers and the second sensor operate using a photovoltaic power system with a minimum autonomy of 72 hours. This system includes a low-battery alert. The installation also includes GPRS/3G communications technology, allowing real-time monitoring of the water level and remote control of the automatic barriers. The barriers can be activated manually (using a key), remotely via a control application, or automatically when the sensor triggers an alert.
As a result, if either level sensor detects water depth equal to or greater than its programmed threshold, the barriers will automatically lower, blocking passage at both stream crossings and sending alerts to the Municipal Police and Civil Protection. This system avoids the need for immediate deployment of police officers during a rainfall event, freeing up resources for other emergency actions. However, barriers will never open automatically—they will only reopen once an order is given, after the Municipal Police have assessed the area and confirmed that it is safe to restore passage.
The status of the sensors and barriers can be monitored via the Sentillo application of the Terrassa City Council at the following link:
http://sentilo.terrassa.cat/sentilo-catalog-web/component/map
