Permeable Paver Calculator

Calculate permeable pavement system design including base course depth, storage volume, and infiltration capacity using ASCE and EPA methodology.

Calculate Permeable Pavement Design

For educational purposes only. Not a substitute for professional engineering judgment.

Input Parameters

Area Properties

Permeable Pavement Area

Surface area of the permeable pavement

Contributing Drainage Area

Additional impervious area draining to pavement

Design Storm

Design Storm Depth

Total rainfall depth for design storm

Storm Duration

hours

Duration of design storm event

Paver and Base Properties

Paver Type

Type of permeable paver surface

Base Aggregate Type

Type of aggregate for base course

Proposed Base Depth

Depth of aggregate base course

Bedding Layer Depth

Depth of bedding layer below pavers

Subgrade Properties

Subgrade Soil Type

Native soil type below aggregate base

Safety Factor

Factor to reduce infiltration for long-term performance

Overflow Type

Method for handling overflow during large storms

Permeable Pavement Design Overview

Permeable pavement systems allow stormwater to infiltrate through the surface into an aggregate base for temporary storage and infiltration to subgrade. They combine stormwater management with functional paved surfaces.

Surface Infiltration - Water passes through paver joints or porous material
Base Storage - Aggregate voids store water temporarily
Subgrade Infiltration - Water slowly percolates to native soil
Drain Time - Should drain within 24-72 hours for water quality

Paver Surface Infiltration Rates

Paver Type	Min (in/hr)	Typical (in/hr)	Max (in/hr)
Interlocking Concrete Pavers	10	100	400
Concrete Grid Pavers	50	200	600
Plastic Grid Pavers	100	500	1000
Porous Concrete	50	300	700
Porous Asphalt	30	200	500
Gravel-Filled Pavers	200	500	1200

Source: ASCE MOP 77 (2006), Manufacturer Specifications

Aggregate Porosity Values

Aggregate Type	Min	Typical	Max
ASTM #57 Stone	0.35	0.40	0.45
ASTM #2 Stone	0.38	0.42	0.48
ASTM #3 Stone	0.38	0.42	0.46
Crushed Stone	0.30	0.35	0.40
Open-Graded Base	0.32	0.38	0.42

Source: ASCE MOP 77 (2006), ASTM Specifications