Colored Detour Routes to Assist during Highway Closures
While traveling near one of Chester County's expressways, you may have noticed small, colored detour signs such as "Green Detour" or "Black Detour". These signs have been installed by PennDOT in the event of an emergency highway closure to help police and emergency crews direct traffic from one interchange to the next adjacent interchange.
North-south highways in Chester County (US 1; PA 100 in West Whiteland, West Goshen, and North Coventry; US 202) use red for southbound detours and blue northbound detours. East-west highways (US 30, US 422) are signed with green for eastbound detours and black for westbound detours. The color orange is occasionally used alternatively where detours from two expressways may overlap.
In the event of such an emergency that requires closure of the highway, PennDOT's message boards, media reports, and/or emergency personnel will direct motorists to use the appropriate emergency detour route.
Maps of the detour routes for all expressways are available in PDF format through the Delaware Valley Regional Planning Commission's Interactive Detour Route Mapping application, known as iDRuM. These maps can be accessed at www.idrum.us.
Summary of Colors:
RED DETOUR = Southbound detour
BLUE DETOUR = Northbound detour
GREEN DETOUR = Eastbound detour
BLACK DETOUR = Westbound detour
ORANGE DETOUR = Alternative color used where detours overlap