BITSDRAIN: Bituminous sustainable urban drainage

Climate change is forcing cities to confront two major challenges in water management: managing stormwater runoff to prevent localized flooding, and coping with prolonged periods of drought. To mitigate these effects, Sustainable Urban Drainage Systems (SUDS) are becoming increasingly important. The BITSDRAIN project tackles this dual challenge by optimizing a solution tailored for urban environments: the use of porous asphalt (mezclas bituminosas porosas) to manage rainwater directly where it falls, enabling its collection for potential reuse or natural infiltration into the ground.

The project is based on the premise that porous asphalt pavements can temporarily store water within their inner structures and convey subsurface flow. During frequent, low-intensity rainfall events, this process effectively reduces surface runoff and delays peak flows, preventing minor flooding and relieving pressure on sewer systems. At the same time, in contexts of water scarcity, the system is designed to retain and route this rainwater, preventing it from being lost in the traditional drainage network and allowing it to be harvested as an alternative water resource for non-potable urban uses.

Collaborative Innovation & Research

Led by the construction and services group Sorigué, which brings extensive expertise in bituminous materials, the project is being developed in close collaboration with two research groups from the Universitat Politècnica de Catalunya (UPC): the Flumen Institute (River Dynamics and Hydrological Engineering) and MATCAR (Construction Materials and Roads).

BITSDRAIN combines physical lab testing—using a scaled physical street model—with the development of an open-source, free-to-use 2D simulation tool. This digital model will allow engineering firms and municipalities to accurately simulate subsurface flow and storage laws, enabling them to design safer, more resilient, and water-efficient urban spaces.

Outcomes Presentation & Technical Workshop

As the project approaches its completion, a closing event will take place on October 27th at UPC during the morning session under the title “BITSDRAIN: Innovation and Results for SUDS Implementation,” where the key findings and solutions will be unveiled. Following this, the afternoon session will feature a specialized Iber training course focused on the application of these new features within the 2D simulation tool. Further details regarding both sessions will be published soon.

Funding: BITSDRAIN CPP2022-009630 funded by the Spanish Ministry of Science, Innovation and Universities/Agencia Estatal de Investigación/10.13039/501100011033/ and by the "European Union Next Generation EU/PRTR: Recovery, Transformation and Resilience Plan for Spain.