Limited documentation exists regarding parameterization of SWMM’s permeable pavement module and whether the output is realistic, particularly for long-term simulations. In this paper, we evaluated SWMM’s ability to replicate discharge and evaporation from three lined permeable pavement stalls. An assessment of parameter sensitivity identified the permeable pavement module’s input parameters with the highest relative sensitivity. Agreement between observations over a 1-year period and output from the calibrated model was inconsistent for 18 modelled rainfall events. While event volumes and shapes were matched relatively well for two concrete paver stalls for simple single-peak events, more complex multi-peak events showed poor agreement for all stalls. The porous asphalt stall was modelled least satisfactorily, due to its retention capacity that cannot be represented in the model. Based on the findings of this study, an evaporation coefficient (between 0.2 and 0.9), should be applied for long-term simulations of permeable pavement for best results.

The hydraulic performance of permeable pavement (PP) systems has been well demonstrated when based on full or partial on-site infiltration, while there is only limited research on lined PP systems built to provide detention and volume reduction by evaporation only. In this study, we tested the performance of commercially available PP components when constructed as lined PP systems with un-throttled discharge to explore basic hydraulic function in a real-life-setting. Four types of PP surface products and three types of sub-base aggregates were tested in six unique combinations, built as side-by-side parking lots into an existing parking area, each stall having a size of 25 m² and 0.5 m of depth with individual lining. Based on 12 months of monitoring precipitation and discharge from each stall, total volume reduction ranged from 3% to 37%. Analysis of up to 22 single events, representing return periods of up to two years, revealed marked detention capacities, expressed as median volume reduction of 40%, spanning 27–69% and median lag time of 1:38 h, spanning 0:39–3:16 h, across all stalls. The considerable range in hydraulic properties can be ascribed to both surface and sub-base properties.

Newly installed permeable pavement (PP) systems provide high surface infiltration capacity, but the accumulation of sediments causes a decrease in capacity over time, eventually leading to surface clogging. With the aim of investigating local sedimentation processes and the importance of restorative cleaning (RC), nine recently built PP systems were tested for their infiltration capacity with and without restorative cleaning (RC) over an interval of 12–14.5 months. The results were related to each site’s unique history of sedimentation. RC significantly improved permeability, but when revisited after approximately one year, the permeability of cleaned surfaces was not significantly better for the RC spots than from their uncleaned neighbouring areas. Relating permeability to the contextual issues revealed that PP perimeter, adjacent bare soil and mismanagement strongly affected the sedimentation process. At two of the sites, sedimentation processes were so advanced that surface permeability was below the level of service (five-year design storm).