Urban Planning, Ecological Transition, Urban Services and Housing

A large part of Barcelona is built above the Baix Besòs and Pla de Barcelona aquifer, meaning there are abundant underground water resources not too deep below ground. One of these resources is groundwater, which is evenly spread around the city’s subsoil.

What is groundwater?

Groundwater is clean water, but not safe to drink. To be apt for human consumption it would need specific treatment and management, but it is suitable for municipal uses such as watering vegetation, cleaning streets, sewerage and the maintenance of springs and ponds where there are native species to preserve.

Groundwater does not rely on short-term weather phenomena and is an important resource which enables us to continue with cleaning and watering tasks in the city. It is actually the only type of water currently being used by municipal services to look after our streets. Groundwater channels exist which were already the usual method for watering in some areas. For their part, cleaning services have a system with 28 water supply trucks which distribute groundwater to smaller cleaning vehicles operating around the city, and gardening vehicles used for watering tasks in parks and gardens.

Sustainable local resource

The terrain itself acts as a deposit for groundwater and the soil filters it and stops any pathogenic agents from proliferating. As it is spread around the city, it is not necessary to build large distribution networks to take water to consumption points. In reality, the groundwater network is organised into isolated systems, each with a well, an extraction pump, a supply tank to regulate water according to demand and a distribution network which mainly tends to be used for cleaning and watering.

The network covers a total distance of 102 kilometres and has 155 service connections. The largest groundwater tank built to date in Barcelona is the one at La Canòpia, in Plaça de les Glòries. It has a capacity of 1,500 cubic metres and is operated remotely, thanks to a control centre. Over 250,000 cubic metres of water was extracted from the wells of La Canòpia in 2023.

More investment in groundwater

The procedure to release 14.4 million euros in emergency funding will help to improve the groundwater network. The seven projects to be carried out should increase the volume of available water for street cleaning and watering by 20%. The work is due to start progressively from March, with the new systems coming into operation in 2025.