Hoogheemraadschap Hollands Noorderkwartier

Hoogheemraadschap Hollands Noorderkwartier (HHNK) is a Dutch regional water authority responsible for the management of water resources, flood defence and water quality in the Hollands Noorderkwartier area of the Netherlands. Its core tasks include the operation and maintenance of dikes, dams, pumping stations and waterways to protect the region from flooding and to ensure adequate water levels for agriculture, nature and urban areas. HHNK also oversees the treatment and discharge of wastewater, monitors surface and groundwater quality, and issues permits for water use and construction activities that could affect water systems. The authority provides information and advice to residents, businesses and governmental bodies on water-related matters and participates in regional planning processes. Its services are aimed at safeguarding the living environment and supporting sustainable water use across the territory it serves.

As a public water board, HHNK operates under the Dutch Water Act and has an independent statutory mandate to regulate and manage water affairs within its jurisdiction, distinguishing it from private utility companies. The organisation’s expertise lies in hydraulic engineering, environmental monitoring and integrated water management, competencies that are essential for coping with climate‑induced challenges such as sea‑level rise and extreme rainfall. In May 2024, a ransomware attack on one of its suppliers, AddComm, led to the temporary hostage of data that included personal details such as names, addresses, citizen service numbers, bank accounts and property information, prompting HHNK to file a provisional data leak notification with Dutch regulators and advise affected parties to verify payment communications. Although HHNK’s own systems were not compromised, the incident highlighted the authority’s reliance on third‑party IT services and its commitment to transparency when data protection risks arise. The water board continues to focus on its primary mission of ensuring safe, clean and sufficient water for the Hollands Noorderkwartier region while maintaining robust security practices for its digital services.