Catalonia's government has updated the urban plan for the future Tres Chimeneas neighborhood in Sant Adrià del Besòs, raising the main street by three meters due to increasing flood risks from climate change. It also plans to densify public housing buildings to add around 100 affordable units. The changes address updated studies and lessons from recent storms.
The urban master plan for the 32-hectare sector, on the former Besòs thermal plant site by the river and sea, now includes stricter flood measures. The current terrain sits about three meters above sea level, but the main street will rise to six meters for a "safe itinerary" passable during floods. "It will be imperceptible, as the neighborhood and park designs already include gentle slopes," sources familiar with the plan explain.
Other steps involve doubling sewer siphon widths, enhancing drainage to the sea, and adding openings in train track fences. José A. Gras, Sant Adrià's deputy mayor for Environment and Urban Planning, notes the "sponge city" approach with absorbent surfaces, floodable planters, and sustainable urban drainage systems (SUD’s). The city council urges Adif to raise the train bridge over the river by 3.5 meters, in its investment plan but not budgeted or scheduled.
For housing, the plan calls for 1,069 market-rate units and 714 protected ones, aiming to add about 100 more by shrinking sizes or common areas. Plataforma 3X opposes densification: "Increasing density means raising the risk," it states in a release, questioning affordability and insufficient green spaces or facilities despite the 90,000 m² park.
Gras stresses mitigation improves resilience: "It is a holistic and integral strategy to address potential river or sea flood risks."
