- Stormwater Management
- Construction Management
Silver Spring, MD
Nobis Engineering was on a multi-disciplined team for the design of a one-story addition to an existing elementary school. The existing site consisted of the school building, a bus drop-off area, a parking lot, associated sidewalks and playing fields. Portions of the northwest and southeast corners of the site are forested. Existing woods were retained to the maximum extent practicable. A 50-foot buffer of the easternmost wooded area was retained.
Viers Mill Elementary school is located at a high point between storm drain systems that join and flow to a tributary in the Lower Rock Creek watershed. The site has four significant drainage divides. The southeast (1) portion of the site drains the majority of the existing building, paved play area, part of the parking areas and the bus drop-off lane to drain inlets in the eastern section of Dahill Road. The northeast (2) and northwest (3) portions of the site contain the existing grass playfields and the northwest corner of the existing building. The roof drains and surface runoff from these areas flow into drainage ditches that connect into a two drain inlets that flow to the storm drain system on Emden Road. The southwest (4) portion of the site contains a small parking area, walks and a stairway to the corner of the existing building. Runoff from the southeast portion flows to inlets connecting to the storm drain system in the western section of Dahill Road. In its former condition, there was no stormwater quality treatment provided onsite.
The redevelopment of the elementary school expanded the existing school building with a one-story addition at the rear of the building to replace classroom portables. The use of retaining walls allows conservation of existing woodland and the creation of an ADA-compliant drop-off loop. The bus loop and parking were re-configured to provide separate access for buses and for parent drop-off. Impacts to the southeast forested were minimized. The northwest wooded area was retained to the maximum extent practicable. The northern area remained as grass playfields but was re-graded to provide proper slopes and adequate drainage.
The Viers Mill Elementary School addition improves the school from a functionality standpoint with added classrooms and additional parking. For environmental sustainability, bioswales, bioretention facilities, and a green roof were added to the building addition to promote stormwater quality and efficient use of the space. Designing the courtyards as 100% pervious provides extra ESD treatment as well.
Nobis provided construction inspection of the stormwater management facilities. The photo highlights the green roof on the building addition.