Before You Begin (BMP-Aligned)
- Meet or exceed your permit & SWPPP. Select, install, and maintain the FODS entrance in accordance with your local SWPPP and stormwater permit requirements (e.g., EPA CGP/NPDES, state/local manuals).
- Call 811 for locates. Request utility locates at least 3 business days before installation—especially if you plan to anchor into soil, asphalt, or concrete. Do not anchor above marked utilities.
- Choose the right spot. Install the FODS system at the primary/only egress point, as close to the roadway as is safely possible; avoid low points where water pools and do not direct run-off to streets or inlets. Add inlet protection if a drain is nearby.
- Prepare the subgrade. Clear large rocks, landscaping, abrupt grade changes, or ruts; fill/compact soft spots to create a flat, stable surface. This improves tire contact and safety.
- Right-size the layout. FODS mats are 12 ft (w) × 7 ft (l) × ~3.75 in (h) and weigh ~420 lb each. Plan the number of mats in series to achieve sufficient tire rotations (a common BMP objective), typically via a 1×5 “T” layout (~35 ft) or longer where needed. (CDOT recognizes ~35 ft of FODS as an alternative to ~70 ft of rock.) Use a “T” for increased turn radius
Optional hardware kits are available to connect mats together. See the Installation Guide for more information.
4 Easy Steps To Install
Step 1
Choose the right construction entrance configuration for your project. Download our layout guide below for more information.
Step 2
Level out or remove any excessive uneven terrain such as large rocks, landscaping materials, sudden abrupt changes in elevation, and similar.
Step 3
Place the mats in the appropriate configuration and then use the Mat Moving Tool to pull the mats into place.
Step 4
Use anchors to secure the mats to the substrate. Optional hardware kits are available to connect mats together. See the Installation Guide for more info.
Design Best Practices
- Entrances/exits. Funnel all site traffic across the FODS mats to maximize performance and compliance.
- Grade to keep stormwater on-site. Maintain positive drainage back into the site (not toward the roadway). Add supplemental BMPs (e.g., inlet protection, berms/diversions) as needed by your SWPPP.
- Provide adequate length for cleaning. Many agencies size stabilized exits for 2–3 full tire rotations of the largest vehicle; FODS achieves the same functional goal with shorter length due to the pyramidal tread-deforming surface. (Example: CDOT’s 35 ft FODS ≈ 70 ft rock.) Scale up on high-traffic or high-fines sites.
- Traffic management. Use signage and cones to direct vehicles entirely over the mats at slow speed (10mph/15kmh); avoid sharp turns on the mat when using tracked vehicles or immediately off the mats unless your layout provides a “T” turn area.
Operations, Inspection & Maintenance
- Daily housekeeping: Inspect nearby paved roads daily; sweep or vacuum to remove any tracked sediment. Increase frequency during wet weather or heavy traffic.
- Mat cleaning threshold: Remove accumulated sediment from between pyramids when buildup approaches ~2.5 inches (or as specified in your plan). Use a street sweeper, skid/broom, or shovel—do not wash sediment into inlets.
- Storm event inspections: Inspect before forecasted rain, daily during extended rain, and after each event; repair, re-anchor, or re-grade as needed to keep the system effective.
- Supplemental controls: On sticky clays or extreme conditions, pair FODS with additional BMPs (e.g., wheel wash upstream of the mats) per your SWPPP.
