Residents and environmental campaigners have again raised concerns over sewage overflows along the Cala de Bou coastline following heavy rainfall, while two nearby beaches were temporarily closed to bathing after a wastewater discharge.

The latest episode has renewed longstanding concerns about the capacity and condition of the sewage infrastructure around Cala de Bou and the wider Bay of Portmany.

Environmental association Salvem sa Badia de Portmany says it received photographs and videos from residents following the intense rainfall over the weekend of October 3 and 4. According to the organisation, several sections of the southern side of the bay were affected by sewage-related overflow from the drainage network.

The material reported along the coast included wet wipes, organic waste and, according to the association, dead rats. Residents also reported strong unpleasant odours in affected areas.

Concerns over the sewage network

Salvem sa Badia attributes the recurring problem to the lack of sufficient separation between rainwater and wastewater networks. The organisation says that during periods of heavy rainfall, the system can become overwhelmed, resulting in wastewater escaping through sewer covers close to the coastline and near pumping stations.

The association is calling for progress on separating the rainwater and sewage networks and for the construction of stormwater retention tanks to reduce the risk of future overflows.

It has also reminded residents and visitors not to flush wet wipes, hygiene products, oils or other inappropriate materials down toilets, as these can contribute to blockages and problems within the sewage system.

Two beaches temporarily closed

The latest rainfall episode was also followed by official bathing restrictions elsewhere along the Sant Josep coastline.

On Sunday, October 4, Cala Tarida and Caló d'en Serral were temporarily closed to bathing following a wastewater discharge. The Ayuntamiento de Sant Josep advised residents and visitors not to enter the water until further notice while the situation was assessed.

The closures demonstrate that the consequences of heavy rainfall and sewage-system incidents are not limited to unpleasant smells or debris on the shoreline, but can also result in precautionary measures to protect bathers.

A recurring problem in Cala de Bou

The latest reports come after several sewage-related incidents in Cala de Bou during 2026.

In July, a major failure in the wastewater network led to sewage escaping onto the coastline and prompted the temporary closure of a nearby bathing area. Subsequent reports also raised concerns about bacterial contamination in samples collected by environmental campaigners.

The Ayuntamiento de Sant Josep has acknowledged the need for a structural solution to the area's sanitation problems. The municipality has said it has commissioned the drafting of a municipal sewerage plan that includes an integral intervention in Cala de Bou, aimed at modernising the wastewater network and preventing future incidents.

The Balearic Government's bathing-water monitoring programme also provides official testing of coastal bathing areas, with assessments based on levels of bacteria including Escherichia coli and intestinal enterococci.

For Cala de Bou and the wider Bay of Portmany, the latest rainfall has once again highlighted the pressure placed on ageing wastewater infrastructure during periods of intense weather.

With further unsettled weather possible in Ibiza, attention will remain on the condition of the sewage network and the quality of coastal waters as authorities and residents continue to deal with the recurring problem.