Infiltration trenches in Kungsbacka, Sweden
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Summary
Flow-weighted sampling was performed at the inlet and outlet of one of the infiltration trenches beneath the parking lot of a supermarket in Kungsbacka, south of Gothenburg. Monitoring ran from April–June 2012 and five storm events were originally analysed. The trench is part of a larger system serving the Maxi ICA site (≈3.1 ha) with three subsurface macadam trenches; the monitored “trench 1” had ~176 m³ storage with a permitted outflow of 6.17 L s⁻¹ (site cap 15 L s⁻¹). Runoff passes an oil separator and then discharges to stormwater ponds located between the car park and the Björkris residential area (toward Björkrisån/Kungsbackaån). Reported pollutant removals were high for TSS and metals and moderate for nitrogen, alongside clear flow attenuation. A subsequent peer-reviewed paper expanded the dataset to seven events and confirmed these trends. More recent municipal stormwater guidance (2023) highlights the Björkris/Hede ponds as part of the local network; while this corroborates the downstream arrangement, publicly available sources do not document the current maintenance or operational status of the specific trenches.
Last update
2025