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    RCG

    Commercial Drainage & Stormwater Contractor

    French drains, catch basins, detention retrofits, and underground storm systems — designed for MS4 post-construction BMP compliance across Cincinnati, NKY, Dayton, and Lexington.

    Drainage Built for MS4 Compliance, Not Just Visual Dryness

    The Ohio EPA's small MS4 general permit (OHQ000004) and Kentucky's KYR10 general construction permit have changed what "drainage installation" means for commercial property owners in our corridor. Hamilton County Storm Water District, SD1 across Boone/Kenton/Campbell counties, Greene County, and LFUCG's Industrial and High-Risk Commercial Stormwater Runoff Program all impose post-construction monitoring on commercial sites. RCG installs drainage systems engineered for MS4 compliance — proper post-construction BMPs, sized to the local water-quality volume requirement, with as-built drawings suitable for the annual MS4 report. We're as comfortable installing a 12-foot dry well behind a Florence office park as we are retrofitting a 50,000-SF parking lot with bioretention cells and PICP infiltration pavement.

    • French Drains: Commercial-grade perforated PVC or HDPE in geotextile-wrapped washed stone trenches — sized to the contributing area and discharge target, not the manufacturer's residential default.
    • Catch Basins & Inlets: Concrete catch basins, ductile iron grates, sediment traps, and DOT-rated inlet structures for parking and roadway scope.
    • Channel Drains: Trench drains across loading docks, drive-through lanes, parking entrances, and ADA-compliant transitions — sloped to a positive outfall.
    • Detention & Retention Retrofits: Adding or expanding detention basins to bring legacy properties into MS4 compliance during a renovation cycle.
    • Bioretention & Rain Gardens: Engineered bioretention cells with proper soil media, underdrain, and overflow — for water-quality credit under post-construction BMP requirements.
    • Underground Storm Systems: StormTech, Cultec, and other infiltration/retention chamber systems for sites where surface detention isn't an option.
    • Permeable Interlocking Concrete Pavement (PICP): Increasingly the post-construction BMP of choice for parking and walkway scope; ICPI-spec install with the right base infiltration rate.

    MS4 Compliance Built In

    OHQ000004 (Ohio EPA's small MS4 permit) is up for renewal 3/31/2026 with expected tightening of post-construction water-quality requirements. We design drainage retrofits with the next permit cycle in mind, not the last one — your detention or BMP install today should still be compliant in 2027.

    Sized to the Local Water Quality Volume

    Hamilton County, Greene County, SD1 (NKY), and LFUCG each define water quality volume slightly differently. We design to the actual local rule — not a national rule of thumb — so the system passes inspection the first time.

    As-Built Documentation Included

    Every drainage installation closes with as-built drawings showing pipe sizes, invert elevations, BMP locations, and infiltration test results. That documentation is what your facility manager needs for the annual MS4 report — and it's what the next contractor will need 10 years from now when the system needs maintenance or expansion.

    Commercial Drainage FAQs

    MS4 stands for Municipal Separate Storm Sewer System. The U.S. EPA's NPDES Phase II rules require many cities and counties to manage stormwater discharge — including imposing post-construction obligations on commercial properties that are larger than certain thresholds. In our corridor, Hamilton County, SD1 (NKY), Greene County, and LFUCG each have post-construction BMP rules that apply to most new commercial development and major renovations. See our MS4 compliance guide for full details.

    A French drain handles localized seepage and surface drainage for small contributing areas. Detention is required when MS4 rules govern the site — typically when impervious area exceeds local thresholds (often 1 acre disturbed or 10,000 SF impervious added). For a 30,000-SF parking lot retrofit, detention is almost always required. For a 1,000-SF entry-walk drainage problem, a French drain plus catch basin is usually sufficient. We assess based on the specific local rule and site conditions.

    Yes. Bioretention cells (engineered soil media + underdrain + overflow) and permeable interlocking concrete pavement (PICP, installed to ICPI specs) are both increasingly specified by civil engineers for post-construction water-quality credit under MS4 rules. We install both, and we coordinate the soil-media specs and infiltration-rate testing required for compliance.

    French drains run $25–$75 per linear foot installed at commercial scale. Commercial catch basins run $1,500–$5,000 each installed depending on depth and DOT rating. Detention retrofits range broadly — $25,000 for a small dry pond expansion to $250,000+ for a fully engineered underground chamber system on a constrained site. Bioretention cells run $30,000–$120,000 depending on size and soil-media depth.

    Both. If your civil engineer has already designed the drainage, we install to those specs and produce the as-builts. For smaller scopes (single drainage retrofit, French drain installation, parking inlet upgrade), we design in-house and pull permits. For MS4-regulated retrofits over a meaningful threshold, we recommend a civil engineer be involved from the start — we have working relationships with civil firms in all four metros.

    Related Resources

    MS4 Compliance GuidePICP & PaversRetaining WallsErosion ControlSite Works Hub

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