Rhode Island Code of Regulations › Title 250 - Department of Environmental Management › Chapter 150 - Water Resources › Subchapter 10 - Wastewater And Storm Water › Part 8 - Stormwater Management, Design and Installation Rules › Section 250-RICR-150-10-8.22 - Permeable Paving

Current through June 14, 2024
A. There are two
				  major types of permeable paving:
1. Porous
				  asphalt and pervious concrete. Although they appear to be the same as
				  traditional asphalt or concrete pavement, they have 10%-25% void space and are
				  constructed over a base course that doubles as a reservoir for the stormwater
				  before it infiltrates into the subsoil or is directed to a downstream
				  facility.
2. Pavers. Three
				  alternative paver configurations will be acceptable to the approving agency as
				  water quality BMPs. These are as follows:
a.
				  Permeable solid blocks or reinforced turf: This type of permeable paving
				  surface includes permeable solid blocks (where the blocks have a minimum void
				  ratio of 15%) and contain open-cell grids filled with either ASTM D448 - 12
				  Standard Classification for Sizes of Aggregates for Road and Bridge
				  Construction, incorporated above at §
												8.4(F) of
				  this Part, No. 8 washed aggregate for (paving blocks) or sandy soil and planted
				  with turf (for reinforced turf applications), set on a prepared base course
				  consisting of a minimum of 1.5 inches of ASTM D448 - 12 Standard Classification
				  for Sizes of Aggregates for Road and Bridge Construction, incorporated above at
				  §
												8.4(F) of
				  this Part, No. 8 washed aggregate, over a minimum of 4 inches of ASTM D448 - 12
				  Standard Classification for Sizes of Aggregates for Road and Bridge
				  Construction, incorporated above at §
												8.4(F) of
				  this Part, No. 57 washed stone. ASTM D448 - 12 Standard Classification for
				  Sizes of Aggregates for Road and Bridge Construction, incorporated above at
				  §
												8.4(F) of
				  this Part, No. 2 washed stone is used as a reservoir course as necessary to
				  manage variable storm sizes or provide other functions.
b. Solid blocks with open-cell joints >
				  15% of surface: This type of paver surface includes interlocking impermeable
				  solid blocks or open grid cells that must contain permeable void areas (between
				  the impermeable blocks) exceeding 15% of the surface area of the paving system.
				  Permeable void areas are to be filled with ASTM D448 - 12 Standard
				  Classification for Sizes of Aggregates for Road and Bridge Construction,
				  incorporated above at §
												8.4(F) of
				  this Part, No. 8 washed aggregate and compacted with a minimum 5,000 lbf plate
				  compactor. Pavers are set on prepared base course materials consisting of a
				  minimum of 1.5 inches of ASTM D 448 -12 Standard Classification for Sizes of
				  Aggregates for Road and Bridge Construction, incorporated above at §
												8.4(F) of
				  this Part, No. 8 washed aggregate, over a minimum of 4 inches of ASTM D448 -12
				  Standard Classification for Sizes of Aggregates for Road and Bridge
				  Construction, incorporated above at §
												8.4(F) of
				  this Part, No. 57 washed stone. ASTM D448 - 12 Standard Classification for
				  Sizes of Aggregates for Road and Bridge Construction, incorporated above at
				  §
												8.4(F) of
				  this Part, No. 2 washed stone is used as a reservoir course as necessary to
				  manage variable storm sizes or provide other functions.
c. Solid blocks with open-cell joints <
				  15% of surface: This type of paver surface includes interlocking impermeable
				  solid blocks or open grid cells that must contain permeable void areas (between
				  the impermeable blocks) less than 15% of the surface area of the paving system.
				  Permeable void areas are to be filled with ASTM D448 - 12 Standard
				  Classification for Sizes of Aggregates for Road and Bridge Construction,
				  incorporated above at §
												8.4(F) of
				  this Part, No. 8 washed aggregate and compacted with a minimum 5,000 lbf plate
				  compactor. In order to meet the water quality treatment requirements of §
												8.9 of this Part, these
				  types of systems must be designed to provide one inch of surface storage above
				  the permeable pavement system. Pavers are set on prepared base course materials
				  consisting of a minimum of 1.5 inches of ASTM D448 - 12 Standard Classification
				  for Sizes of Aggregates for Road and Bridge Construction, incorporated above at
				  §
												8.4(F) of
				  this Part, No. 8 washed aggregate, over a minimum of 4 inches of ASTM D448 - 12
				  Standard Classification for Sizes of Aggregates for Road and Bridge
				  Construction, incorporated above at §
												8.4(F) of
				  this Part, No. 57 washed stone. ASTM D448 - 12 Standard Classification for
				  Sizes of Aggregates for Road and Bridge Construction, incorporated above at
				  §
												8.4(F) of
				  this Part, No. 2 washed stone is used as a reservoir course as necessary to
				  manage variable storm sizes or provide other
				  functions.