Observation Road Relocation

About the Project

Observation Road at Piper Lane is impassable several times per year due to flooding from adjacent Broad Run. When flooded, landside access to the west side of the airfield is restricted, causing tenants and Air Traffic Control Tower (ATCT) staff to access the west side by driving through the airfield from an open gate. It can take upwards of 48 hours for the floodwaters to recede. The project includes relocating a portion of Observation Road so that it is above the 100-year floodplain (refer to Figure 1-1), which will significantly reduce flooding impacts and will allow for the future redevelopment of the site. The work will also prepare the West Corporate Development site located on the northwest corner of Manassas Regional Airport.

Figure 1-1: Existing Floodplain

The project will include the construction of a perimeter retaining wall to raise the relocated road and portions of the site that are prone to flooding. A new section of Airport-maintained Observation Road will be constructed from the existing portion of Observation Road that runs along the west perimeter of the airfield to a point adjacent to the existing Airport gate southwest of the Dulles Aviation hangar. In addition, a stormwater detention pond and a stormwater system will be completed with the anticipation of future redevelopment of the Dulles Aviation site. See Figure 1-2 for a depiction of the road relocation.

Figure 1-2: Proposed Observation Road Relocation

Project Schedule

Below is an estimated project schedule from preliminary design through the start of construction. This schedule will be refined once the project moves into final design during Winter 2020-2021.

Description Date
Preliminary Design Kick-Off November 2019
Preliminary (50%) Design Completed June 2020
Conditional Letter of Map Revision (CLOMR) Submittal to Federal Emergency Management Agency (FEMA) July 2020
CLOMR Approval from FEMA December 2020
Begin Final Design December 2020
Bid Advertisement April 2021
Bid Opening May 2021
Construction Notice to Proceed August 2021