The NRUCFC Headquarters project is located in the NRUCFC Campus, which is within the Dulles Town Center project in Loudoun County, Virginia. Dulles Town Center is a 540-acre high density mixed used development. When Dulles Town Center was originally planned for stormwater management in the early 1990s, it was done on a regional basis using regional stormwater management facilities. These facilities were designed and constructed to accommodate the future tenants and uses within Dulles Town Center, which includes the NRUCFC Campus. Due to the presence of shallow rock and the low permeability of the existing soils, infiltration measures were not feasible options as stormwater management facilities within Dulles Town Center. The NRUCFC Campus, currently an undeveloped parcel, is planned to be developed as an office park, with the NRUCFC Headquarters project being the 1st building. The NRUCFC Campus drains an on-site regional pond identified as BMP (Dry Pond) Facility at Ramp C (CPAP 1994-0081). Runoff to this facility is detained in a dry pond and discharged directly into a major floodplain downstream. This pond was designed, approved and built in accordance with County BMP standards at the time, which were based on the Occoquan Method in the document entitled, Northern Virginia BMP Handbook - A Guide to Planning and Designing Best Management Practices in Northern Virginia, 1992. LEED stormwater management criteria were not in existence at the time. Today, meeting LEED stormwater management criteria is not required within Loudoun County. However, to meet the intent of SSc6.1 (existing imperviousness of
The project team is requesting whether their efforts to reduce the post-development stormwater discharge rate and quantity from their low permeability site meets the intent of the credit, even though they are still above the pre-development levels. Based on the description provided, the project does not meet the intent of the credit. However, if the stormwater management plan was expanded to include additional on-site quantity control strategies (such as a rain catchment system), AND stream channel protection strategies, then the project could pursue the Option 1B compliance path in the NCv2.2 Reference Guide. Applicable Internationally.