Porous asphalt and porous concrete are poured and cured in place , while other materials are precast and can be installed without needing to be cured . The County ’ s Permitting Standards outline specific requirements for installing porous / pervious asphalt in Appendix J ( Charleston County Stormwater Program Permitting Standards and Procedures Manual , 2017 ), as provided below :
Contact surfaces such as curbing , gutters , and manholes shall be painted with a thin , uniform coat of Type RS-1 emulsified asphalt immediately before the asphalt mixture is placed against them . The temperature of the asphalt mixture , at the time of discharge from the haul vehicle and at the paver , shall be between 275-325 degrees Fahrenheit , within 10 degrees of the compaction temperature for the approved mix design .
The porous asphalt shall be placed within a single application at a minimum two ( 2 ) inches thick or in two lifts . If more than one lift is used , measures must be taken to ensure that the porous asphalt layers join completely . Time between layer placements must be kept minimal and the first layer clear from dust and moisture . Traffic should be kept at a minimum on the first layer . Protect all exposed surfaces that are not to be treated from damage during all phases of the pavement operation The asphalt mixture shall be spread and finished with the appropriate equipment .
The mixture shall be struck off in a uniform layer to the full width required and of such depth that each course , when compacted , has the required thickness and conforms to the grade and elevation specified . Pavers shall be used to distribute the mixture over the entire width or over such partial width as practical . In areas where irregularities or unavoidable obstacles make the use of mechanical spreading and finishing equipment impractical , the mixture shall be spread and raked by hand tools .
No material shall be produced so late in the day as to prohibit the completion of spreading and compaction of the mixture during daylight hours , unless night paving has been approved for the project . No traffic will be permitted on material placed until the material has been thoroughly compacted and has been permitted to cool to below 100 degrees Fahrenheit . The use of water to cool the pavement is not permitted . The Engineer reserves the right to require that all work adjacent to the pavement , such as guardrail , cleanup and turf establishment , is completed prior to placing the wearing course when this work could cause damage to the pavement . On projects where traffic is to be maintained , the Contractor shall schedule daily pavement operations so that at the end of each working day all travel lanes of the roadway on which work is being performed are paved to the same limits . Suitable aprons to transition approaches , where required , shall be placed at side road intersections and driveways as directed by the Engineer .
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NATURE-BASED SOLUTIONS MANUAL FOR KIAWAH ISLAND