Every exterior drainage system we install on a commercial property works with the grade of the land. Catch basins collect water that the grade directs toward them. French drains intercept water that is moving through the soil following the natural slope. Swales convey surface flow along a designed path toward a controlled outlet. Detention basins sit at the lowest designed point on the site and receive the water that the overall site grade directs to them. If the grade of the site is wrong, none of the drainage infrastructure below it works the way it should.

On a well-graded commercial site, every paved and unpaved surface sheds water away from buildings and toward collection points, at a rate and in a direction that the downstream drainage infrastructure was designed to handle. Water moves predictably, accumulates where it is supposed to, and exits the site through a controlled discharge point. On a poorly graded site, water moves toward buildings, pools on paved areas, saturates soil at the wrong locations, and arrives at drainage collection points in volumes or directions that the existing infrastructure was not designed to manage.

Grading and regrading is the exterior drainage correction that fixes the problem at its source. It is the work that makes every other drainage system on the site perform correctly, and it is work that requires someone who understands drainage, not just someone who knows how to move dirt. A grading contractor who does not understand how water behaves on a site after the earth is moved can create new drainage problems while appearing to fix existing ones. We approach every commercial grading project as a drainage design problem, and the grading plan we execute is built around the drainage outcome we are designing toward.

A commercial site where the surrounding grade slopes toward the building rather than away from it directs surface water from every rain event toward the foundation perimeter. This is the grading condition that creates persistent foundation perimeter saturation, accelerates exterior foundation wall deterioration, and generates the hydrostatic pressure conditions that drive moisture through foundation materials over time. In many cases this condition results from original construction grading that did not account for long-term soil settlement, or from subsequent landscaping modifications that redirected grade toward the building without recognizing the drainage consequence. Regrading the area around the building perimeter to restore proper positive drainage away from the structure is the exterior correction that addresses the source of the problem.

Commercial sites undergo soil settlement over time, particularly in areas where fill was placed during construction. Settlement can flatten or reverse original design grades, creating low spots that accumulate water, altering the drainage path that surface runoff was designed to follow, and changing the relationship between the site grade and the drainage infrastructure installed to match it. A catch basin that was positioned at a low point when the site was new may no longer be at the lowest point after a decade of settlement. We reassess the current site grade, identify where it no longer matches the original drainage design intent, and regrade to restore the drainage performance the site was designed to achieve.

Parking lots and access roads require adequate cross slope to shed surface water toward catch basins and edge drains rather than allowing it to pool on the pavement surface. When pavement is laid without adequate cross slope, or when the base settles unevenly after installation, water pools on the pavement surface, accelerates pavement deterioration, creates safety hazards, and adds runoff volume to areas where the site drainage system was not designed to collect it. We assess pavement cross slope conditions and work with the pavement contractor on regrading or resurfacing solutions that restore proper surface drainage.

Commercial sites that sit at the base of a slope or adjacent to a higher-elevation neighboring property receive runoff from those sources in addition to the rain falling directly on their site. When the grade of the site at the boundary where that runoff arrives does not direct it toward a collection point, it spreads across the site, saturates the soil in unpredictable locations, and adds to the drainage load the site infrastructure needs to handle. Grading corrections at the receiving boundary combined with a curtain drain installation intercept and manage that offsite contribution before it reaches the interior of the site.

Commercial sites that have been modified over time through additions, parking lot expansions, new access roads, or landscaping changes often develop grade conflicts between different sections of the site where drainage from one area is directed toward another area that was not designed to receive it. A building addition that changes the grade relationship between the original structure and the adjacent parking lot, or a new access road that intercepts a drainage swale and redirects surface flow, are examples of site modifications that create drainage problems by altering the original grade design. We assess the full site drainage picture and design grading corrections that resolve the conflicts between site features without creating new ones downstream.

A grass-lined swale is the most common swale type on commercial sites. It is constructed by shaping a shallow channel in the soil surface at a consistent designed slope, seeding it with an appropriate grass mix, and protecting the newly seeded surface with erosion control blanket until vegetation establishes. Grass-lined swales slow surface water velocity, which reduces erosion along the swale channel and allows sediment to settle out of the flow before it reaches the downstream catch basin or detention basin. They are effective at managing moderate runoff volumes across large open areas of a commercial site and are a required component of many commercial stormwater management plans.

Swales constructed parallel to commercial access roads and parking lot edges convey surface water that sheets off paved surfaces along the pavement edge toward a catch basin or discharge point at the end of the road or lot. They serve the same function as a curb and gutter system on a public road, but in a less expensive and more flexible form that is appropriate for many commercial site configurations. We construct roadside swales to the correct cross section and slope to convey the runoff volume from the contributing pavement area without overtopping the swale banks during design storm conditions.

Commercial development projects subject to stormwater management requirements frequently include swale systems as a specified best management practice in the approved plan. These swales are designed to specific channel dimensions, slopes, and discharge rates that the stormwater management plan requires for compliance. We install swales to the specifications in the approved plan, working from the design documents provided by the licensed civil engineer who prepared the plan. Where the plan requires constructed outlet protection at the downstream end of the swale to prevent erosion at the discharge point, we install that protection as part of the swale installation scope.

Some commercial stormwater management plans specify bioretention swales, also called biofiltration swales or vegetated filter strips, that are designed not just to convey runoff but to filter pollutants from the water as it moves through the vegetated channel. These systems use specific soil media, vegetation types, and channel dimensions to provide water quality treatment as well as runoff conveyance. Where the applicable stormwater management plan requires a bioretention swale, we construct the channel to the specified dimensions and soil media requirements and establish the required vegetation.

From that assessment we develop a grading plan with specific drainage outcomes in mind. The plan identifies the target grades at the building perimeter, the slope directions and magnitudes needed to shed water toward collection points, the swale alignments and dimensions required to convey surface flow across open areas, and the discharge points where corrected grade and swale systems will route water off the site. We do not move dirt and then evaluate what it did to site drainage afterward. The drainage outcome drives the grading plan from the beginning.

Simple grading corrections along the building perimeter on a mid-sized commercial lot are a different scope from a full site regrading project on a large industrial property with multiple grade conflicts and an extensive swale system required by a stormwater management plan. We provide free on-site assessments for commercial properties and deliver detailed estimates with itemized pricing before any work begins. All grading and swale work we complete is backed by our 5-year workmanship warranty.

Drainage Pro of CT provides commercial site grading, regrading, and swale installation for properties across 13 towns on the Connecticut Shoreline. We are based in Clinton and serve commercial properties from East Haven and Branford in the west to East Lyme and Old Lyme in the east, and inland through Killingworth, North Branford, and Durham. If you have been searching for landscape grading contractors near you, commercial land grading near you, or yard grading services for a commercial property on the Connecticut Shoreline, we are the dedicated exterior drainage company serving your area.

If your commercial site has surface water moving toward your building instead of away from it, paved areas that pool after rain events, open areas with no controlled surface drainage path, or grade conditions that are contributing to drainage problems elsewhere on your site, we are ready to come out and assess it. We serve commercial property owners, facilities directors, and property managers across the Connecticut Shoreline and we will give you a clear and honest exterior grading and drainage plan with itemized pricing before any work begins. No pressure. No guessing. Just a grading and swale solution built for your site.

Commercial Site Grading and Swale Installation on the Connecticut Shoreline

Site Grading Is the First Stormwater Management Control on Every Commercial Property

Common Commercial Site Grading Problems on the Connecticut Shoreline

Site Graded Toward the Building

Settled or Subsided Site Grade

Inadequate Cross Slope on Paved Areas

Offsite Runoff Arriving at Grade

Grade Conflicts Between Site Features

Commercial Drainage Swale Design and Installation

Grass-Lined Drainage Swales

Roadside and Parking Lot Edge Swales

Swales as Part of Stormwater Management Plans

Bioretention Swales

How We Approach Commercial Grading and Regrading Projects

Commercial Grading and Swale Installation Cost

Commercial Grading and Swale Contractors Serving the Connecticut Shoreline

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