Reservoir logic
Base storage = paver area x stone depth x stone void space. The calculator compares that storage with rainfall on the surface.
RainYard Tools
Stone reservoir
Permeable Paver Base Calculator
Compare permeable paver base storage with rainfall landing on the surface.
Base storage698 galWater held in stone voids.
Rain on surface185 galWater from the selected event.
Margin+513 galStorage exceeds event.
Example
A 350 sq ft paver area with 8 inches of stone and 40% voids stores about 698 gallons in the base.
Storage is not the same as infiltration
The stone base can hold water temporarily, but the site still depends on soil infiltration, underdrains, and overflow.
Driveways need structural design
Vehicle loads, base depth, edge restraint, and local frost conditions matter. Use this as a water-volume screen only.
Questions
Common checks.
Can permeable pavers replace a drain?
Sometimes they reduce runoff, but they still need soil, storage, and overflow checks.
What stone void space should I use?
Clean open-graded stone is often estimated around 35-45% void space.
Helpful referencesEPA permeable pavement overview