Alabama Trackout Control Requirements

Alabama is a year-round construction state. With an average annual rainfall of more than 50 inches statewide, construction runoff is a persistent concern from the Tennessee River Valley in the north to the Gulf Coast in the south. The state's geography creates dramatically different soil conditions across its regions: red clay soils in the Appalachian foothills around Birmingham and Tuscaloosa, the heavy black clay of the Black Belt running diagonally across central Alabama, and the sandy coastal plains stretching from Montgomery down to Mobile Bay. Each of these settings presents distinct challenges for aggregate-based construction entrances, and the Black Belt in particular is notorious for clay soils that clog the void spaces in gravel pads within days of installation.

The construction industry in Alabama is among the most active in the Southeast. Automotive manufacturing facilities operated by Mercedes-Benz, Honda, Hyundai, and Toyota have driven decades of industrial and supplier development across the state, with the I-65 corridor from Huntsville through Birmingham to Montgomery functioning as the spine of that economy. Huntsville's aerospace and defense sector, anchored by Redstone Arsenal and NASA's Marshall Space Flight Center, supports a sustained volume of commercial and infrastructure construction that ranks Madison County among the fastest-growing counties in the South. The Port of Mobile and the surrounding Baldwin County coast generate continuous residential and commercial development along the Gulf Coast. All of this construction activity occurs under a statewide stormwater regulatory framework that requires stabilized construction access as a foundational best management practice on every project above the permit threshold.

Any project disturbing one or more acres of soil in Alabama must obtain NPDES permit coverage from the Alabama Department of Environmental Management before construction begins. Stabilized construction access is not optional under that coverage; it is a BMP requirement embedded in both the state permitting framework and the Alabama Department of Transportation's standard specifications.

ADEM Construction Stormwater General Permit

The Alabama Department of Environmental Management (ADEM) administers the Construction Stormwater General Permit (CGP) under NPDES authority delegated by the U.S. Environmental Protection Agency. The permit number is ALR100000. The prior permit was issued March 12, 2021, became effective April 1, 2021, and expired March 31, 2026. ADEM initiated reissuance in early 2026, with reissuance Notice of Intent applications due March 2, 2026. Contractors beginning new projects in 2026 should confirm current permit coverage requirements and the effective date of the reissued permit directly through ADEM's construction stormwater program page at adem.alabama.gov.

Permit coverage is required for any land-disturbing activity that exposes one or more acres of soil, or for any activity smaller than one acre that is part of a larger common plan of development or sale expected to disturb one acre or more in aggregate. To obtain coverage, operators must submit a Notice of Intent (NOI) to ADEM before ground disturbance begins. The NOI must be accompanied by a Construction Best Management Practices Plan (CBMPP) that identifies anticipated sources of sedimentation and pollution and documents the BMPs the operator will implement to minimize discharges to Alabama's waters.

The CBMPP is the functional equivalent of the SWPPP used in many other states. It must document all active BMPs by type and location, identify responsible parties, establish inspection schedules, and describe corrective action procedures. ADEM requires that the CBMPP be maintained on site throughout active construction and updated whenever conditions change. Sediment-laden discharges from permitted sites can result in inspection findings, permit violations, civil penalties, and notice of non-compliance. Any visible sediment that reaches a water body or leaves the site perimeter requires prompt corrective action and documentation.

The Construction Exit Pad: Alabama's Gravel Pad Standard

The primary technical guidance for construction stormwater BMPs in Alabama is the Alabama Handbook for Erosion Control, Sediment Control, and Stormwater Management on Construction Sites and Urban Areas, published by the Alabama Soil and Water Conservation Committee (ASWCC). The Handbook establishes the standard BMP specifications that contractors, inspectors, and project engineers use statewide. A companion Field Guide for Erosion and Sediment Control on Construction Sites in Alabama (most recent edition 2022) provides illustrated, field-ready summaries of the same BMPs for use during site inspections.

The Handbook's BMP for trackout prevention is the Construction Exit Pad (CEP-1). ADEM defines the Construction Exit Pad as "a stone base pad or manufactured product that provides a buffer area to remove mud and caked soil from vehicle tires at ingress and egress points." The explicit inclusion of manufactured products in that definition is significant: it establishes from the outset that compliant alternatives to stone-based pads are acceptable within Alabama's BMP framework when properly documented in the CBMPP.

Standard stone-based dimensions. When aggregate is used, CEP-1 specifies a pad approximately 50 feet in length, 20 feet in width, and a minimum of 6 inches in depth. The stone must be ALDOT coarse aggregate gradation No. 1 — the same large-rock gradation used in ALDOT construction specifications. Construction exit pads must be installed at all locations where construction traffic exits onto active public roadways, and must remain in place throughout the period of active grading and excavation on the site.

Maintenance. Like gravel pad standards in other states, the Alabama CEP-1 requirement carries an implicit maintenance burden. As aggregate fills with sediment fines and loses void space, trackout performance degrades. In Black Belt soils, where clay content is extremely high, gravel pads can become saturated and compacted quickly, requiring replenishment or full replacement to remain effective. Any sediment tracked onto public roads must be removed the same day by dry methods; hosing sediment from a road surface into a storm drain or drainage channel is prohibited.

FODS on the ALDOT Miscellaneous Approved Products List

The Alabama Department of Transportation has listed FODS by brand name on the ALDOT Miscellaneous Approved Products List (List X-2) as an approved product for construction entrance applications. The listing reads:

PEB 4608 — FODS TRACKOUT CONTROL MATS/1100TCM | Manufacturer: FODS, LLC | Approval Date: February 3, 2020

The ALDOT List X-2 is the formal approved products registry that ALDOT contractors, project engineers, and inspectors use to confirm that a construction material or product meets ALDOT performance requirements. For construction entrance applications, contractors on ALDOT projects are required to select from products on the List X-2 when specifying a manufactured alternative to the standard stone pad. FODS has been on that list since February 2020, meaning any contractor on an ALDOT project can specify FODS directly without submitting a product substitution request or equivalency justification.

The List X-2 approval applies statewide across all ALDOT construction programs and is maintained on ALDOT's Materials and Tests Division website. The list is periodically updated as new products are evaluated and approved.

ALDOT Highway Projects and Section 665

Projects on the Alabama Department of Transportation right-of-way, or funded through ALDOT contracts, are governed by ALDOT's standard specifications alongside the ADEM permit requirements. The relevant specification section is Section 665: Temporary Soil Erosion and Sediment Control, which covers all erosion and sediment control BMPs required on ALDOT construction projects. The associated standard drawing is ESC-502, which provides the detailed dimensions for a Stabilized Construction Entrance on ALDOT projects.

Under ESC-502, the standard ALDOT stabilized construction entrance is 15 feet wide and 50 feet long unless the project plans specify otherwise. The stone must be ALDOT Size #1 coarse aggregate. The Size #1 specification uses large-rock gradation specifically to prevent smaller stones from tracking off the pad and onto adjacent pavement or travel lanes — a safety concern that parallels the aggregate specification rationale WSDOT identified in its construction access standard.

For contractors specifying a manufactured trackout control product on an ALDOT project, the List X-2 Miscellaneous Approved Products List is the required reference. FODS Trackout Control Mats appear on that list under PEB 4608 as an approved Construction Entrance product. A contractor substituting FODS for the ESC-502 stone pad cites the List X-2 listing as the approval basis and documents the substitution in the project's CBMPP or ALDOT erosion control plan.

ALDOT manages a substantial volume of active construction across Alabama at any given time. The I-65 corridor from the Tennessee border south through Huntsville, Birmingham, and Montgomery to Mobile carries significant freight and commuter traffic and is the subject of ongoing interchange, widening, and safety improvement projects. The I-20/I-59 corridor connecting Birmingham to the east and west, the completed I-22 connecting Birmingham to Memphis through the northwest corner of the state, and I-85 from Montgomery to the Georgia state line all carry active ALDOT construction programs. US-72 in the Tennessee Valley, US-280 through the Appalachian foothills, and US-431 down the eastern corridor are among the state routes where ALDOT and local agency projects run continuously.

The Alabama Handbook and ASWCC Guidance

The Alabama Handbook for Erosion Control and the companion Field Guide are the reference documents that ADEM inspectors, ALDOT inspectors, and local permitting staff use to evaluate BMP adequacy in the field. Both documents describe the Construction Exit Pad as a preventive BMP and include the ALDOT coarse aggregate gradation No. 1 specification for stone-based installations. The Handbook's definition of CEP-1, "a stone base pad or manufactured product" creates the opening for contractors to document manufactured trackout control systems within the CBMPP without requiring a formal variance or alternative BMP approval from ADEM.

The Alabama Soil and Water Conservation Committee, which publishes the Handbook, also coordinates Alabama's participation in the Southeast Region's broader erosion and sediment control standards development. That regional context means Alabama's BMP requirements have evolved in step with neighboring Georgia, Tennessee, and Mississippi, and manufactured mat products that carry approvals in those states tend to be familiar to Alabama inspectors and project owners as well.

FODS Trackout Control Mats

FODS Trackout Control Mats are high-density polyethylene (HDPE) panels that replace aggregate-based construction exit pads. Each panel is molded with a pyramid-protrusion surface pattern that flexes and deforms vehicle tires as equipment drives across. That mechanical deflection dislodges sediment, clay, and debris from tire contact surfaces before vehicles reach public roads.

The mat system installs without gravel, compaction, or earthwork. A standard deployment of interconnected panels takes under 30 minutes. Panels interlock and can be configured to any access width and length, then relocated as site access points shift between construction phases. At project close, panels are removed and reused on the next site, generating no demolition waste and no aggregate disposal obligation.

Alabama's Black Belt soils present a particular maintenance problem for traditional gravel pads. The heavy clay in that region — the same clay that gives the Black Belt its name and its characteristic dark color — has virtually no compatibility with open-graded aggregate. Clay particles fill void spaces rapidly, the pad surface becomes a clay sheet rather than an aggregate filter, and trackout performance disappears. Replenishing a clay-saturated gravel pad requires excavating the contaminated material, hauling it away, and installing new stone — a cost that can approach or exceed the cost of the original installation. A solid HDPE mat surface is impervious to clay migration: the surface stays effective regardless of the soil type at the construction access, and accumulated material is removed by dry sweeping rather than aggregate replacement.

Along the Gulf Coast and in the coastal plains of south Alabama, sandy soils present a different challenge. Fine sand tracks readily from tire treads and becomes airborne on hot days, creating both sediment discharge and nuisance dust conditions. A rigid mat surface that strips sand from tire treads before vehicles reach the pavement offers consistent performance in conditions where the Alabama Handbook's CEP-1 stone pad may become buried, displaced, or insufficient.

How to Specify and Use FODS on an Alabama Project

For contractors and engineers documenting FODS in a CBMPP or ALDOT erosion control plan:

For private development projects under ADEM ALR100000: Identify the Construction Exit Pad (CEP-1) BMP in the CBMPP. Under the pad type, specify FODS Trackout Control Mats and note that manufactured trackout control products are explicitly included within the Alabama Handbook's CEP-1 definition. For projects adjacent to ALDOT right-of-way or visible to ALDOT inspectors, reference the ALDOT List X-2 listing (PEB 4608) as supplemental documentation of product approval.

For ALDOT highway projects under Section 665: Cite the ALDOT List X-2 Miscellaneous Approved Products List, PEB Number 4608, as the primary approval basis. Reference ESC-502 as the substituted standard drawing. Document the FODS configuration (panel quantity, access width, and effective length) in the project's erosion control plan. Confirm the substitution with the project's resident engineer or ALDOT construction inspector at preconstruction to ensure the List X-2 listing is current and acceptable on the specific contract.

For local government projects: Confirm whether the jurisdiction has adopted a local erosion control ordinance that specifies its own BMP list. If the local ordinance references the Alabama Handbook, CEP-1's manufactured-product language applies. If the local authority has its own approved products list, the ALDOT List X-2 listing can be presented as supporting documentation. In jurisdictions without a specific local requirement, ADEM permit coverage and a properly documented CBMPP establish the compliance baseline.