Benevento is facing a renewed political and environmental dispute over persistent bad odours, foam in the Calore River, and reported fish deaths, with Mayor Clemente Mastella rejecting opposition criticism and saying the environment is protected through formal acts and rigorous procedures.

The controversy centres on odour complaints linked to an organic-waste or biogas facility in the Contrada San Domenico area, alongside environmental concerns around Ponte Valentino and the Calore River. Residents in Benevento and nearby communities including Pesco Sannita and Pietrelcina have sought answers about odours near the organic-waste treatment plant, while opposition councillors have demanded greater transparency, access to official records, and a more direct institutional response.

The dispute intensified during a Benevento city council meeting, where majority and opposition councillors clashed over odours in Contrada San Domenico and Ponte Valentino, foam observed in the Calore, fish deaths, and the adequacy of the municipal response.

What the municipality says it has done

Mastella argues that the city's environmental record should be judged on administrative and technical measures rather than political debate. According to the municipal account reported by NTR24, the city adopted urgent restrictive measures against the biomass plant, including suspension or interdiction of activity and an order to remove residual biomass and other odour-generating material.

The Environment Councillor has separately said the municipality activated the competent bodies and procedures, leading to inspections and sampling by ARPAC, the ASL health authority, and the Forest Carabinieri. Following ARPAC findings, the biogas plant was suspended, according to that municipal account.

The municipality has also pointed to investigations involving the Ponte Valentino wastewater facility. Available reports state that relevant infrastructure was placed under preventive or judicial seizure during the investigation. Mastella has further said that tests by ASL and Gesesa confirmed the safety and potability of the city water supply.

Foam in the Calore and fish deaths

Dense white foam appeared in the Calore River, and fish deaths were reported, adding to public concern alongside the odour complaints. The causes have not been conclusively established in the available material and remain connected to an ongoing investigation.

The reports describe inspections, sampling, and technical investigations by ARPAC, ASL, Forest Carabinieri, and other competent bodies, as well as a pending Prosecutor's Office investigation. The official results of all river and wastewater sampling are not published in the material reviewed, and the complete laboratory datasets have not been made available.

A political clash over transparency

Mastella has framed the conflict as a political dispute with the opposition, maintaining that dialogue is impossible with the current opposition figures. In his words: "Ambiente si tutela con gli atti e il rigore."

Opposition and resident criticism, by contrast, has focused on transparency and institutional presence: requests for official records, clearer communication of monitoring results, and faster answers for neighbourhoods affected by odours and river conditions.

What remains unresolved

Several central questions are still open:

  • The definitive cause of the odours, river foam, and fish deaths has not been established in the acquired reporting.
  • The precise legal status and current operating status of each facility involved require confirmation from official municipal, ARPAC, or judicial records.
  • Claims about drinking-water safety have been reported, but the underlying laboratory results and complete datasets were not provided in the available material.
  • Both the administration's claims and the opposition's counterclaims have largely been presented through politically interested or media sources; independent publication of the underlying test data is still needed.

For residents near Contrada San Domenico, Ponte Valentino, and the Calore River, the next meaningful steps will be publication of sampling results, clarification of the operating restrictions on the plants, and updates from judicial and environmental authorities on the ongoing investigations.