UNIVERSITY OF NORTH CAROLINA - CHAPEL HILL
STORMWATER MANAGEMENT PLAN AND IMPLEMENTATION
University of North Carolina Facilities and Planning Department
Chapel Hill, North Carolina
Environmental Planning
UNC Chapel Hill brought Cahill Associates into their Master Planning Process to address the environmental components of their future development plan. Cahill Associates and team members were hired to formulate a long term strategy for sustainable stormwater management in order to meet the current program needs and also comply with the regulatory framework of both Town and State, setting the stage for implementation of the more comprehensive program throughout the entire campus.

To accomplish this, CA developed a stormwater model within a GIS to evaluate existing and future conditions on campus, as well as to evaluate the effectiveness of various stormwater recommendations. Both existing and future stormwater volume and pollutant loads generated from new surfaces were estimated with the models. The model was used to test various BMPs and recommended land use changes to evaluate these recommendations in terms of stormwater volume, pollutant reduction, and cost.

Porous Parking Lots
In coordination with this overall planning effort, CA and the University have implemented sustainable stormwater management strategies in recent development projects. CA designed two large, porous pavement parking lots with groundwater recharge for the university. These lots are the first large porous pavement systems in North Carolina, and were recognized in 2002 by the NC State Engineering Council, receiving their highest "Grand Conceptor" award.

Ram's Head Center
Cahill Associates were brought onto the planning team for a new 750-car parking garage, new recreation and dining facilities, and a new "plaza" area on the roof of the parking garage. The concepts of Green Building Design and the goals of the campus Environmental Master Plan were incorporated into the design process for Ram's Head.

The building footprint was dramatically reduced to protect the steep wooded slopes and pathways of the valley. The parking garage is built on the site of an existing parking lot and is partially underground, with the new plaza and buildings located on top of the three-story garage. A rooftop plaza serves as a "green roof" for stormwater management, as water held on the roof will meet irrigation needs and reduce potable water use.

Adjacent hillside drainage is collected and infiltrated in the stormwater storage/ infiltration bed located beneath Ehringhaus athletic field. This bed provides significant stormwater storage and management for the UNC campus. The historic springs, previously piped, are daylighted in a new low flow stream channel adjacent to the new playfield.
Site Photographs
  
This 1-acre Green Roof Plaza is atop a 700-car garage. Stormwater is stored in a 55,000 + gallon cistern under the walkways and is used to irrigate the landscaping.

UNC Chapel Hill is known for its wooded, green campus...
...but is rapidly becoming urbanized from increased development pressures.

The Estes Commuter parking lot incorporates porous asphalt, porous concrete, and standard asphalt combined with subsurface infiltration beds to manage stormwater runoff.
The Friday Center parking also incorporates porous asphalt and concrete with subsurface infiltration.