Stormwater management is a priority in urban areas, and Barcelona is no exception. Participants in the LIFE in Runoff project were able to learn about the solutions in the Spanish city during a city visit.

Barcelona is a city with a rich historical and cultural heritage, but also faces many of the challenges that have accompanied the city’s rapid development and growth over the last thirty years. Intense rainfall and stormwater drainage problems are common in Barcelona, which is why city leaders are using innovative methods to manage stormwater sustainably. In this article, we look at the main problems related to stormwater management in Barcelona, the solutions adopted by the city and one of the key tools for sustainable stormwater management, the Sustainable Water Management Systems (SuDS).

Barcelona and rainwater

As in the case of Budapest, climate change in Barcelona presents two challenges to those who manage rainwater: the distribution of rainfall has become unpredictable in recent years, with months of drought followed by months of sudden downpours of huge amounts of rain.

In 2023, Spain is going through its most turbulent period in decades, and its prime minister, Pedro Sánchez said.that “drought will be a central political and territorial debate for our country in the coming years.” This is why the proper management and retention of rainwater has become essential both in Spain and in Barcelona.

Barcelona in numbers in the light of rainwater management

    • The canal system is 1648 km long
    • 115 m3 of water per year passes through the network
    • 1540000 inhabitants and 98 square kilometres of commercial and industrial facilities
    • there have been heavy rains, with 40% of the annual rainfall falling in 2-3 days
    • the upper parts of the city represent an increase of up to 40%
    • green spaces infiltrate up to 70% of rainwater, while roads and pavements only infiltrate 5%
    • additional water treatment infrastructures: 40000 m of wells, 60000 m of gutters, about 391200 cubic metres of rainwater cisterns

Innovative solutions: sustainable drainage systems (SuDS)

Traditional drainage systems alone cannot adequately drain rainwater, and drought has put increasing emphasis on retention and reuse, in addition to drainage. To achieve this, the Barcelona municipality is using a number of innovative solutions, managed in an integrated system called SuDs.

Sustainable Drainage Systems (SuDS) are solutions that treat stormwater as close to its source as possible to mimic natural drainage and promote infiltration, slowing and passive management .

Sustainable water management systems (SuDS) are design solutions that aim to manage rainwater sustainably in the natural landscape. SuDS allows rainwater to be naturally absorbed, stored and run off slowly, reducing the rate of run-off and minimising the risk of flooding.

One of the main solutions is to improve urban green infrastructure. Barcelona encourages the creation of green roofs, vertical gardens and parks in urban areas. In addition to the rain gardens, ecologically valuable areas such as artificial ponds and swamps have been created, which also help to absorb and filter rainfall naturally.

In addition, Barcelona will install rainwater harvesting systems in public areas and buildings. Rainwater harvesting systems help to collect and reuse rainwater for various purposes, such as irrigation or washing. This will reduce urban water consumption and improve rainwater harvesting.

The use of SuDS in Barcelona is not limited to water treatment, but also has a positive impact on the livability of the city. Green spaces increase urban biodiversity, improve air quality and have a cooling effect on urban temperatures.