How artificial turf manages water

Flooding is about volume, infiltration, storage, and a place for water to go. A modern artificial turf system is intentionally permeable. Water passes through the backing into an open graded aggregate base that stores and moves it to soil or a planned outlet.

The system at a glance

  • Perforated or fully permeable turf backing for rapid vertical flow.
  • Stabilized, open graded aggregate base that provides void space for temporary storage.
  • Geotextile separation where needed to keep fines from migrating up into the base.
  • Optional underdrains or French drains that tie to a safe outfall on tight or clay sites.
  • Smart edge details that do not trap water at curbs, mow strips, or hardscape transitions.

Permeability numbers that matter

Many turf products are lab tested at 30 inches per hour or more. In real yards, the base design often controls performance. A 4 inch open graded base with 30 to 40 percent voids can store roughly 0.75 to 1.0 gallon of water per square foot before it even needs to infiltrate or discharge.

When flooding happens and how to prevent it

Common causes of water problems

  • Flat or back pitched grades that push water toward the house.
  • Too little base depth for the drainage area and rainfall intensity.
  • Fine materials in the base that reduce voids and slow flow.
  • No outfall on clay or compacted subgrade that infiltrates poorly.
  • Trapped edges where concrete, curbs, or edging create a dam.

Design specs that stop headaches

  • Do a quick infiltration check of native soil to decide if you need an underdrain.
  • Use open graded aggregate with consistent chip sizes and minimal fines.
  • Typical lawn areas do well with 4 to 6 inches of base. Increase depth for larger catchment areas or heavier rainfall.
  • Maintain a subtle slope of about 1 to 2 percent toward a safe discharge point.
  • Add a perforated pipe or French drain on clay, tight urban lots, or where outfall is required by code.
  • Keep edge restraints low or notched so water can exit, not pond.

Runoff comparison

  • Artificial turf with a permeable base is designed to infiltrate and temporarily store water, reducing peak flow compared with hardscape.
  • Natural grass over compacted soil often sheds water once saturated, which can increase runoff and surface mud.
  • Concrete and pavers without permeable joints are effectively impervious and shed water immediately.

Maintenance to keep water moving

  • Blow or brush off leaves and sediment that can clog surface pores.
  • Groom infill as needed to keep fibers upright and water paths open.
  • Clear perimeter drains, scuppers, and curb cuts each season.
  • Rinse high traffic or pet areas so fines do not accumulate.

Special site conditions

Clay soils or high water table

Use a thicker open graded base plus an underdrain connected to a code compliant outfall. Consider a geotextile to keep fines from migrating.

Steep slopes

Bench or terrace long slopes, key the base into the subgrade, and install check slots or drains that intercept and redirect flow.

Rooftops and balconies

Use a panel or pedestal system over waterproofing and keep clear pathways to roof drains. Verify load and detailing with the building professional.

Installer checklist

  1. Confirm drainage area, rainfall intensity, and soil infiltration.
  2. Set finish grades with a defined outfall path.
  3. Build an open graded base to the required depth and compaction.
  4. Protect the base from fines during construction.
  5. Install optional underdrains where infiltration is limited.
  6. Detail edges so water can enter and exit freely.
  7. Water test before infill and final brush.

Cost and budget signals

  • More base depth and underdrains add cost but buy reliable performance.
  • Smart grading during site prep often reduces the need for extra drainage hardware.
  • Quality turf with proven permeability protects your investment long term.

Proof you can ask for

  • Manufacturer permeability data for the turf backing.
  • Base gradation spec and void ratio from your installer.
  • Photos or video of a hose test after base buildout.
  • Plan or sketch showing outfall routing where required.

Next step

Want a site-specific drainage plan for your project? Ask a FusionTurf dealer to assess soil, slopes, and outfalls, then size the base and any underdrains to fit your property.