Problem 1 A hotel project is to be developed in an open space of 1.477 acres in San Jose. After development, the project site will consist of building structure, driveway, parking area, walkway, landscape area, and open area. They are denoted by "DMA" and are described in the following table. The post-construction stormwater will be controlled by an infiltration basin located in the open area and by pervious concrete pavement installed in the driveway and parking areas. Based on the Urban Runoff Quality Management approach, please (1) design the pervious concrete pavement and (2) determine the size of the infiltration basin. Please note: The required drawdown time for the infiltration basin is 48 hours. The in-situ infiltration rate is 2.1 in/hr for the project site. The mean annual precipitation at the project site is 14.4 inches. Required capture of stormwater runoff is 80%. Traffic index is 5 and California R-value is 6 for driveway and parking areas. Infiltration rate for the pervious concrete pavement is 2 in/hr. Time to fill the infiltration basin is 2 hours. Post-development Characteristics of DMAS Sub-area Description Area (sq-ft) Impervious (%) DMA-1 Building Structure 12,494 100 DMA-2 Driveway 18,354 0 DMA-3 o 14,556 Parking Area Walkway 3,047 DMA-4 100 DMA-5 0 11,433 Landscape Area DMA-6 0 4,454 Open Space Problem 1 A hotel project is to be developed in an open space of 1.477 acres in San Jose. After development, the project site will consist of building structure, driveway, parking area, walkway, landscape area, and open area. They are denoted by "DMA" and are described in the following table. The post-construction stormwater will be controlled by an infiltration basin located in the open area and by pervious concrete pavement installed in the driveway and parking areas. Based on the Urban Runoff Quality Management approach, please (1) design the pervious concrete pavement and (2) determine the size of the infiltration basin. Please note: The required drawdown time for the infiltration basin is 48 hours. The in-situ infiltration rate is 2.1 in/hr for the project site. The mean annual precipitation at the project site is 14.4 inches. Required capture of stormwater runoff is 80%. Traffic index is 5 and California R-value is 6 for driveway and parking areas. Infiltration rate for the pervious concrete pavement is 2 in/hr. Time to fill the infiltration basin is 2 hours. Post-development Characteristics of DMAS Sub-area Description Area (sq-ft) Impervious (%) DMA-1 Building Structure 12,494 100 DMA-2 Driveway 18,354 0 DMA-3 o 14,556 Parking Area Walkway 3,047 DMA-4 100 DMA-5 0 11,433 Landscape Area DMA-6 0 4,454 Open Space