Ibiza Town Council has outlined plans to expand stormwater storage and improve urban drainage following the flooding caused by DANA Adam. Mayor Rafael Triguero presented the measures during the municipal debate on the state of the municipality on Wednesday, 21 October, including additional stormwater tanks and a hydrogeological plan to help identify interventions that could reduce the risk of future flooding.

The announcement comes as the municipality continues to face questions about the capacity of its drainage infrastructure following repeated episodes of intense rainfall.

Additional Stormwater Tanks Planned

Triguero has announced plans for new stormwater tanks and further improvements to the city's rainwater drainage systems.

Stormwater tanks temporarily store rainwater during periods of heavy precipitation, helping to manage peak flows and reduce pressure on drainage infrastructure. Their effectiveness depends on factors including storage capacity, location and the capacity of the wider drainage network.

However, details of the newly proposed installations have not yet been specified. The number of tanks, their locations, construction budgets and anticipated start dates remain unconfirmed.

The announcement therefore represents a stated intention to expand the municipality's stormwater infrastructure rather than a fully detailed construction programme with a published delivery schedule.

Ibiza Already Has a Stormwater Tank in Platja d’en Bossa

The municipality has already completed one stormwater tank on Fray Luis de León Street in Platja d’en Bossa.

The installation was confirmed as complete by Ibiza Town Council in June 2026. It has an approximate capacity of 1,000 cubic metres and was built at a cost of €968,000.

The infrastructure is designed to regulate rainwater flows, reduce the direct discharge of contaminated water towards the beach and help filter water in the event of overflows.

The council has also undertaken other drainage improvements, including work on rainwater networks and infrastructure in different parts of the municipality. The newly announced tanks would represent a further expansion of these efforts, although their proposed locations and technical specifications have not yet been published.

Hydrogeological Plan Already Included in Aqualia Contract

The hydrogeological plan highlighted by Triguero is not an entirely new proposal. It was already included in the municipality's new water supply and sanitation concession, signed with Aqualia on 8 October 2026.

The 20-year contract provides for €17 million in investment during its first eight years. The programme includes the renewal of water supply and sanitation infrastructure, new separate rainwater drainage networks and the preparation of a hydrogeological plan.

The study is intended to analyse how water moves through the municipality and help determine the measures needed to reduce flood risk and improve the management of rainwater.

The contract also provides for a separate infrastructure improvement fund worth approximately €2 million annually.

These commitments form part of a broader programme to modernise the municipal water system. However, the overall investment figure should not be interpreted as a dedicated budget for the newly proposed stormwater tanks, for which specific funding details have not been announced.

DANA Adam Puts Drainage Infrastructure Under Renewed Pressure

The announcement follows the severe rainfall and flooding associated with DANA Adam on 18 and 19 October.

The Balearic Government reported that the Pityusic Islands accumulated up to 190 litres of rainfall per square metre over a 24-hour period during the episode. Torrents overflowed, roads were affected and flooding prompted a significant emergency response across Ibiza and Formentera.

The latest storm has renewed attention on the ability of existing drainage systems to cope with intense rainfall, particularly in areas vulnerable to water accumulation.

The proposed expansion of stormwater storage, together with the hydrogeological study and improvements planned under the water concession, forms part of the municipality's stated approach to strengthening its hydraulic infrastructure.

The practical impact of the proposals will depend on the findings of the study, the projects ultimately selected and the funding and construction schedules established for the additional infrastructure.