Erosion & Drainage Control

Silt fence, inlet protection, stabilized construction entrances, check dams, and the perimeter controls a permitted site must have in place before disturbance begins. Installation follows the SWPPP's control drawings, and the work does not end at installation: controls are maintained, repaired after storm events, and adjusted as construction phases move disturbance around the site. When areas reach final stabilization, temporary controls are removed and the ground they occupied is restored.

Open channels and swales cut and shaped to the lines, grades, and cross-sections on the civil plans — lined or unlined as the design directs. Grade control matters as much here as in a sewer trench: a swale built flat holds water against the very areas it was designed to protect. Channel work is coordinated with mass grading so drainage paths are established as the site takes its finished shape, not carved in afterward.

Cross-drainage culverts, headwalls, safety end treatments, and outfall structures built where concentrated flow enters and leaves the site. At outfalls, energy dissipation — rip-rap aprons, rock protection, stilling areas — is placed to the details in the plans so discharge does not scour the channel it enters. On energy sites and long access corridors, culvert work is sequenced with road construction so crossings go in before traffic needs them.

Basins that serve double duty: many detention ponds are built early to function as sediment basins during construction, then cleaned, shaped to final section, and converted to their permanent role at project close-out. We build embankments, control structures, and emergency spillways to the civil design, with the earthwork discipline basin performance depends on. Full pond scope — detention, retention, and stock ponds — is covered under pond construction.

Cut and fill slopes protected with erosion control blankets, turf reinforcement matting, and rock protection where the design calls for it, plus the seedbed preparation that gives permanent vegetation a chance to establish. Final stabilization is what closes out a construction permit, so this work is planned from the start rather than left to the end. On constrained sites where slopes cannot hold the grade change, the answer is often a retaining wall instead.

On a permitted site, yes — and the permit is explicit about it. Construction stormwater permits require designated controls to be installed before land disturbance begins, and the first inspection after a storm event will document whether they were. Beyond compliance, the practical case is just as strong: the first storm on a cleared, unprotected site erodes the material your grading plan counted on and deposits it where it must be excavated again. Perimeter controls and a stabilized entrance are among the least expensive items on a civil site and among the most expensive to have skipped. We install them as the first order of work, before the first tree comes down.

Construction-phase controls — silt fence, inlet protection, check dams, sediment basins — are temporary measures that manage runoff while the site is disturbed; they are maintained through construction and removed once ground is stabilized. Permanent drainage — channels, culverts, storm structures, detention — is infrastructure on the civil plans that serves the development for its life. The two systems overlap in time and often in space: a detention pond may spend construction working as a sediment basin, and a permanent channel may carry construction runoff long before it carries its design storm. Building both with one contractor keeps the temporary system from damaging the permanent one, and vice versa.

The stormwater pollution prevention plan and the permit documents are prepared by the owner's engineer or environmental consultant — not by the contractor installing the controls. Compliance inspections follow the permit's requirements: routine inspections and post-storm inspections, documented, with deficiencies corrected on a defined clock. TerraTek's role is field execution — installing the controls the SWPPP shows, maintaining and repairing them through construction, and removing them at stabilization — plus building the permanent drainage on the civil plans. That division of responsibility is deliberate: the party who wrote the plan verifies it, and the party building the site executes it.

Yes. General contractors regularly carry SWPPP installation and maintenance as its own line item, and we price it that way — installation, storm-event maintenance, and removal at stabilization, with the permanent drainage structures priced from the civil sheets. The scope gets stronger when it is bundled: when the same contractor holds grading and controls, phasing conflicts disappear, disturbed acreage is managed deliberately, and drainage structures are built as their grades arrive instead of after the fact. Both models work; the difference is how many seams your schedule has to manage. The bundled version lives under turnkey site development.

Send the drainage sheets, the SWPPP or its control drawings if they exist yet, and the grading plan — the three documents this scope lives between. Use our contact page and include location, disturbed acreage if you know it, and the construction schedule the controls will have to live through. We respond with a scope breakdown that separates construction-phase controls, maintenance, and permanent drainage structures, states what is excluded, and flags anything in the water plan that looks like it will fight the phasing. If the SWPPP is still being written, we can price from the civil sheets and true up when it issues.