Engineer: stream buffer, root‑zone disturbance force need for waivers; board weighs alternatives

At the hearing the applicant’s civil engineer explained why the proposed subdivision layout required disturbance of the stream buffer and removal of several specimen trees. Under cross‑examination the engineer clarified the technical basis for the applicant’s waiver requests and the limits placed by the county’s forest conservation manual.

Engineered evidence: the engineer testified that “any tree that has a disturbance of more than 30%, then that tree will be considered dead,” explaining that DPZ treats disturbance of the critical root zone as equivalent to tree removal and that the proposed stormwater management facility must be sited in the parcel’s low point. He said some specimen trees were in poor or fair condition and that root‑zone disturbance from grading and driveway easements would require alternate compliance under the forest conservation subtitle.

Board members used the engineer’s testimony to examine alternatives: members asked whether the pond could be relocated or whether the front driveway could be extended, and the engineer testified that constraints (lot shape, 50‑foot separation rules for driveways, and slope) made alternate designs infeasible in his professional judgment. Those engineering points were central to the board’s finding that strict compliance would create an “unwarranted hardship” for this lot.