7. A proposed development consists of 300,000 ft2 of pervious parking, onto which the runoff from impervious roof, impervious pavement structures, and contiguous undeveloped land drain. The maximum volume of runoff estimated in a the 2-yr storm, including all areas of the development, is 60,000 ft3. Structural analysis indicates that a depth of 6 in. of a pervious concrete with 20% porosity will be appropriate. Gravel with a porosity of 40% is also available if needed. The parking will be placed on a soil with an infiltration rate of about 1 in/hr.
a. Using this set of data only, determine if the system design is appropriate to accommodate the entire runoff volume of the 2-yr storm