A rainfall simulator for laboratory experimentation is developed to test hydrological performances of micro-detention pond permeable pavement, MDPP. Rainfall characteristics consisting of rainfall intensity, spatial uniformity, raindrop size, and raindrop velocity show that natural rainfall is simulated with sufficient accuracy. The rainfall simulator used pressure nozzles to spray water for rainfall intensity from 40 to 220mm/hr. Uniformity distribution test gives coefficient of uniformity of 95% over an area of 1m2. The raindrops falling at velocity ranging from 0.5 to 15m/s with drop sizes diameter between 2 to 5mm. Free drainage system below the rainfall simulator is accompanied with outlet tanks attached with ultrasonic sensor devices to record the outflow data. During the experiments, the outflow received is 98% in average. Experiment results in typical runoff hydrograph and percolation rate of the MDPP system. This shows the ability of the rainfall simulator to obtain initial hydrology data to aid in the design of the MDPP prototype.

In this study, a permeable pavement with an on-site subsurface micro-detention pond was developed. Common permeable pavements are typically composed of fine layered particles attributed with low porosity. The permeable pavement with micro-scale detention storage (PPDS) developed in this study is a modified type of interlocking block permeable pavement consisting of a hollow cylinder with a hexagonal cover at the top and bottom of the PPDS. The PPDS was designed with a void volume of 70% and a water storage capacity of 0.19 m 3 /m 2. A rainfall simulator was used to perform the tests on the profile of the hydrological pavement such as the storage capacity, detention period, permeability rates and infiltration performance over various storm events. The PPDS showed its ability to detain first flushes of rainfall within a 15-minutes period for a 100 year return period. Meanwhile, the permeability rate of the PPDS was subjected to the infiltration capacity of the subgrade soil following a linear relationship between the flow depths over time. The testing performances indicated that the PPDS has met the basic hydrological design considerations, as those in the typical permeable pavement, from the perspective of permeability rates, infiltration capacity, storage and detention capability.

The purpose of this paper is to study stormwater management potential of new permeable pavement with subsurface micro‐detention storage (PPDS) at low‐speed residential suburban area. The main features incorporated permeable pavement of a hollow micro cylinder precast structure with solid hexagon precast concrete as top and bottom covers. The purpose of hollow micro detention design is for rainwater holding and void between the sets is for self‐drying through the side and bottom seepage during rain. The hydrological parameters were obtained from laboratory rainfall simulator experiment. The performance was evaluated via simulation with Storm Water Management Model (SWMM). The outcomes from the physical model matched well with SWMM. A case study was then developed to assess the hydrological impact of PPDS with the existing condition and other types of permeable pavements. Significant variance was observed, where PPDS displayed its best hydrological performances for stormwater management with the presence of subsurface detention storage.

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