Siting a School on a Sloped Wooded Parcel
An 18-acre parcel is being planned for an elementary school. Slopes range from 6% on the upper terrace to 14% near the low corner. A 0.6-acre wetland occupies the low corner and has a 50-foot regulatory buffer. An arterial road runs along the north edge with measured noise of 68 dBA at the property line. A mature oak-hickory woodland covers about 7 acres in the center of the site. The program includes a 60,000-square-foot building, two acres of playfields, a bus loop, and 120 parking spaces. The client wants the building visible from the arterial and the playfields close to the building. A stream enters the wetland from the east and leaves at the southwest corner. The site has no public water or sewer at the frontage; extensions would cross the woodland.
1. Describe how you would build a suitability map and use it to locate the building, playfields, and parking.
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I would build the suitability map as a weighted overlay of slope, hydrology, soils, noise, tree cover, and access. Slope classes would be 0–4% (best for playfields and parking), 4–8% (buildable with grading), 8–15% (limited), and over 15% (avoid). The wetland and its 50-ft buffer become a no-build constraint, as does the stream corridor. I would map the woodland by size and species, then assign preservation value rather than treating all trees equally.
The building should sit on the upper terrace near the arterial for visibility and bus access, but not on the noisiest edge. A earth berm and preserved tree buffer along the arterial can reduce noise at the building face; the building itself can be set back and oriented with service areas away from classrooms. Playfields need the gentlest grades, so they belong on the upper terrace or a graded bench, not on the 14% slope. Parking should be near the arterial and bus loop, with stormwater treatment in islands and perimeter swales. Crossing the woodland with utilities would be a last resort; I would test an alternative utility route along the road frontage before accepting woodland disturbance.
2. What stormwater and tree protection strategy follows from the analysis?
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The stream and wetland make stormwater a design driver, not a utility afterthought. I would use a treatment train: rooftop disconnection and cisterns at the building, bioretention in parking islands, vegetated swales along the playfield edges, and a constructed wetland or forebay before discharge to the existing wetland. Grading should keep runoff on the upper terrace long enough to infiltrate where soils allow, and should avoid concentrating flow into the buffer.
Tree protection should follow the same logic. I would delineate tree protection zones at the critical root radius, route grading and utilities outside them, and require a certified arborist to review the final plan. The woodland is an asset for shade, noise buffering, and stormwater, so I would preserve a contiguous block rather than scattered specimens. If the bus loop or parking must clip the woodland edge, I would show the exact clearing limits on the grading plan and require a pre-construction meeting with the contractor. The goal is to make the development envelope explicit so that clearing is a deliberate decision, not a construction convenience.