From Reactive to Resilient Maintenance of Urban Drainage Infrastructures for Healthy Coastal Environments (2026–2030)

Protecting coastal and marine environments requires major reductions in pollutant loads from urban catchments. Stormwater runoff is a key transport pathway for diffuse contaminants, many of which are particle-bound and transported with sediments through urban drainage infrastructures (UDI), where they are captured to reduce their spread to receiving waters. However, as sediments accumulate, UDI lose treatment capacity and may shift from pollutant sinks to sources, particularly when operation and maintenance (O&M) are insufficient, infrequent or inappropriate, leading to remobilisation of accumulated sediments and pollutants to coastal and marine waters.

There is currently no standard or data-driven approach to optimise the frequency and method of sediment removal. Municipalities therefore rely on reactive or fixed-interval maintenance, despite its inefficiency and growing inadequacy under climate-driven increases in rainfall intensity. As sedimentation-based systems within UDI, including both conventional assets such as gully pots and nature-based solutions such as stormwater ponds are increasingly implemented, the mass of sediments and associated contaminants retained in these systems will continue to grow, amplifying both management challenges and potential environmental risks.

Fully characterising and addressing these challenges within a wider technical and socio-economic context is essential to ensure that the accumulation of sediments prevents, rather than simply defers their discharge to coastal environments. The project takes a systems-level approach to transform how urban drainage infrastructures are maintained, moving from reactive and schedule-based practices towards proactive, data-driven and environmentally responsible strategies. By combining high-resolution monitoring, predictive modelling and field-based assessment of maintenance practices with legal, governance and economic analysis, the project develops and tests integrated solutions that identify WHEN, WHERE and HOW maintenance should be carried out, reducing pollutants loads to coastal waters while improving system performance and climate resilience.

The project is a multidisciplinary collaboration led by Luleå University of Technology—bringing together Urban Water Engineering, Law and Economics—in partnership with Stockholm Vatten & Avfall, Tecomatic AB and the Swedish University of Agricultural Sciences. It is funded by FORMAS under the call “Blue Transformation – Coast and Sea” with SEK 30 million and runs from July 2026 to June 2030.

Involved in the project at Luleå University of Technology participates in addition to the contact persons below from Urban Water Engineering: Maria Petterson (Law), Oskar Johansson (Law), Kristina Ek (Economics), Patrik Söderholm (Economics)