Stormwater Analysis & Erosion/Sedimentation Control Plans

Challenge & Solution

Rhea performed stormwater analysis and erosion and sedimentation control plans for two communications tower sites designed by an engineering firm for a large communication company. Both “flagpole” sites consisted of a square compound connected by a driveway to the nearest road.

Despite their similarities, the two sites possessed contrasting regulatory requirements and physical landscapes that required differing approaches. Rhea adapted to these requirements to produce results with short turnaround time and minimal background information provided by the Client.

Project Description & Highlights

The site in Fairview, Pennsylvania occupied flat, low lying farmland and required a 20 percent reduction in peak runoff. Analysis showed that a conventional stormwater retention pond was not a feasible solution because of the small area available and the shallow topographic relief at the site.

After considering the use of a permeable pavement infiltration system, Rhea recommended that that the area of pavement at the site be reduced enough that local regulations would no longer require a stormwater plan for the development. The Client agreed and eliminated unnecessary paved areas, meeting local regulations, and reducing runoff to the watershed.

The site in Centerville, Pennsylvania, sat at the top of a steep hill. The municipality required that the development do no harm to downstream waterways. Rhea created a TR-55 model of the watershed, which demonstrated that the paved surfaces to be added during the development would not significantly change the runoff characteristics of the watershed, and therefore not harmfully increase downstream runoff.

 Unnecessary paved areas were eliminated to waive the requirement for a stormwater site development plan.


North Carolina