Pervious grid systems use interlocking plastic frames to create stable, load-bearing surfaces that allow rainwater to soak into the ground below. Filled with gravel or planted with turf grass, these systems serve areas with moderate foot or vehicle traffic while maintaining permeability—reducing stormwater runoff, erosion, and flooding.

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The Problem:
Many landscape areas need stable surfaces that can handle foot traffic, light vehicles, or heavy use—but conventional concrete and asphalt create large impervious expanses. These surfaces generate significant stormwater runoff, radiate heat during warm months, and often eliminate green space that could otherwise absorb rainfall.
The Solution:
Pervious grid systems provide structural support while keeping the ground permeable. Different plastic grid products are designed to withstand a range of weight loads for different purposes in the landscape. Typically, grid systems are used in multi-use areas with moderate foot or vehicle traffic, such as parking spaces or walkways. For aesthetic purposes, small pea gravel, shell, or turf grass can be used as the final surface and is stabilized by the durable plastic grid frame.
Location Requirements
Pervious grass or gravel grids can be used in parking areas, paths, walkways, or as a structural base for a small storage shed. Overflow parking, lawn erosion problem areas, patios, and high-use green spaces are also good candidates. They can be located to accept runoff from nearby less-pervious landscape areas, but the grid system and stormwater reservoir beneath will need to be designed with larger dimensions.
Design Specifications
First, 6 to 12 inches of soil in the work area should be removed to make way for the pervious grid system layers and stone. The stone sub-base layer depth depends on the amount of stormwater desired to be contained during a rain event.

See the in Action

Interlocking plastic grid panels are placed on a prepared base of compacted stone and bedding material. The grids create a structural matrix that distributes weight evenly across the surface while maintaining open cells that allow water to pass through. Beneath the grid, layers of angular stone provide temporary storage and allow stormwater to slowly infiltrate into the underlying soil.

Practice Type: Structural surface infiltration with flexible fill options

Fill Options: Pea gravel, shell, or turf grass

Applications: Parking areas, walkways, patios, overflow parking, erosion-prone lawn areas

Subsurface Storage: 3+ inches of stone reservoir with 40% void space

Added Benefit: Reduces heat radiation compared to conventional concrete or asphalt

Maintenance

Task
Frequency
Details

Inspect fill material

Seasonally

Check for bare spots in turf or empty/low spots in gravel; repair with sandy loam and seed or matching stone

Erosion prevention

Ongoing

Stabilize surrounding area with vegetation or erosion repairs to prevent sediment from washing onto grid

Mowing (grass grids)

During growing season

Use bag attachment or blow clippings off after mowing; maintain 3.5–4.0-inch height for healthy, drought-resistant turf

Weed control

During growing season

Pull weeds or apply herbicide spray to prevent clogging of pervious features

Debris removal

Seasonally

Blow leaves and debris from grid system and nearby drainage areas to prevent organic matter accumulation