Delaware Route 100
|Maintained by DelDOT|
|Length:||8.97 mi (14.44 km)|
|Brandywine Valley National Scenic Byway|
|South end:||DE 4 near Elsmere|
| DE 2 in Elsmere
DE 34 near Elsmere
DE 48 near Wilmington
DE 141 near Wilmington
DE 52 in Greenville
DE 92 in Montchanin
|North end:||SR 3100 at Pennsylvania border near Montchanin|
Delaware Route 100 (DE 100) is a state highway in New Castle County, Delaware. The route runs from DE 4 near Elsmere to the Pennsylvania border near Montchanin, where it continues into Pennsylvania as State Route 3100 (SR 3100, Chadds Ford Road). The road runs through suburban areas of northern New Castle County. It intersects with DE 2 in Elsmere and DE 34 north of Elsmere before forming separate concurrencies with DE 48 and DE 141 from west of Wilmington north to Greenville. In Greenville, there is an interchange with DE 52. North of Greenville, DE 100 continues by itself to the Pennsylvania border, intersecting DE 92 in Montchanin. DE 100 was first designated in the 1930s to run from DE 52 to the Pennsylvania border, where it originally connected to Pennsylvania Route 100 (PA 100). By the 1970s, it was extended south to DE 4. The route was realigned to follow parts of DE 48 and DE 141 by 1990.
DE 100 begins at an intersection with DE 4 southwest of Wilmington, heading north on the one-way pair of Race Street northbound and South Dupont Road southbound. The one-way pair, which carries two lanes in each direction, passes through suburban residential areas. Both directions of the route join, with the route continuing northwest as South Dupont Road, a four-lane divided highway. DE 100 curves north and enters Elsmere, where it runs through industrial areas and comes to a bridge over CSX's Philadelphia Subdivision. A short distance later, the route crosses DE 2 and becomes North Dupont Road, where it becomes an undivided road and comes to a bridge over an East Penn Railroad line. The road continues through wooded residential areas, leaving Elsmere and becoming South Dupont Road. The route reaches an intersection with the eastern terminus of DE 34. Following this intersection, DE 100 passes to the east of a cemetery before reaching an intersection with DE 48.
At this point, DE 100 turns northwest to form a concurrency with DE 48 on four-lane undivided Lancaster Pike, passing through business areas before crossing the East Penn Railroad. The road continues through residential and commercial areas, widening into a divided highway as it comes to an intersection with DE 141. Here, DE 100 splits from DE 48 by turning northeast to join DE 141 on four-lane divided Centre Road. The road runs through industrial areas, curving north and becoming a freeway past the Barley Mill Road intersection. The freeway curves northeast and passes under the East Penn Railroad before coming to a partial cloverleaf interchange with DE 52 in Greenville. Past this interchange, the road curves east and the freeway ends, with DE 100 splitting from DE 141 at an at-grade intersection by heading north on two-lane undivided Montchanin Road.
DE 100 continues north through wooded areas with fields and homes, crossing the East Penn Railroad line again. The road runs through Montchanin and passes to the east of the Wilmington Country Club and the Winterthur Museum and Country Estate before crossing the railroad tracks again. The route intersects the western terminus of DE 92 on the western edge of Brandywine Creek State Park. At this point, the road continues straight as DE 92, with DE 100 turning north to remain on Montchanin Road. The road crosses under the East Penn Railroad again and curves northwest. DE 100 bends to the north again before reaching its northern terminus at the Pennsylvania border, where the road continues into that state as SR 3100 (Chadds Ford Road). The Montchanin Road portion of DE 100 is part of the Brandywine Valley National Scenic Byway, a National Scenic Byway and Delaware Byway.
DE 100 has an annual average daily traffic count ranging from a high of 41,949 vehicles at the Barley Mill Road intersection along the DE 141 concurrency to a low of 2,040 vehicles at the Pennsylvania border. The portion of DE 100 concurrent with DE 141 is part of the National Highway System.
By 1920, what is now DE 100 existed as a county road. The route north of Kennett Pike was proposed as a state highway by 1924. The highway was paved by 1931. By 1932, the state highway had been completed from Elsmere north to the Kennett Pike while the remainder was still a county route. DE 100 was designated by 1938 to run from DE 52 in Greenville north to the Pennsylvania border, where it continued as PA 100. The route was extended south to DE 4 by 1971, following Dupont Road. DE 100 was realigned to bypass a portion of Dupont Road by following DE 48 and DE 141 by 1990. In 2002, the Montchanin Road portion of DE 100 was designated as part of the Brandywine Valley Scenic Highway in the Delaware Scenic and Historic Highways system; it was designated a National Scenic Byway in 2005. In 2003, PA 100 was truncated in Pennsylvania. However, DE 100 remains unchanged. On February 24, 2015, the bridge carrying DE 100 over the East Penn Railroad in Elsmere was closed after concrete fell from the bridge deck onto the railroad tracks below. Emergency repairs are underway and the bridge is expected to be reopened by the end of March.
The entire route is in New Castle County.
|Elsmere||0.00||0.00||DE 4 (Maryland Avenue)||Southern terminus|
|0.73||1.17||DE 2 (Kirkwood Highway) – Wilmington|
|1.41||2.27||DE 34 west (Faulkland Road)|
|Wilmington||1.64||2.64||DE 48 east (Lancaster Avenue)||South end of DE 48 overlap|
|2.67||4.30|| DE 48 west (Lancaster Pike) – Hockessin, Lancaster
DE 141 south (Centre Road) – Newport
|North end of DE 48 overlap, south end of DE 141 overlap|
|Greenville||3.86||6.21||DE 52 (Kennett Pike) – Greenville, Wilmington||Interchange|
|4.12||6.63||DE 141 north (Barley Mill Road)||North end of DE 141 overlap|
|Montchanin||6.26||10.07||DE 92 east (Thompson Bridge Road)|
|8.97||14.44||SR 3100 north (Chadds Ford Road)||Pennsylvania state line, northern terminus|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi
- Staff (2011). "Traffic Count and Mileage Report: Interstate, Delaware, and US Routes" (PDF). Delaware Department of Transportation. Retrieved May 17, 2012.
- Delaware Department of Transportation (2008). Delaware Official Transportation Map (PDF) (Map). Dover: Delaware Department of Transportation. Retrieved November 24, 2015.
- Google (February 6, 2011). "overview of Delaware Route 100" (Map). Google Maps. Google. Retrieved February 6, 2011.
- "Brandywine Valley Scenic Byway". National Scenic Byways Program. Retrieved July 28, 2015.
- "Brandywine Valley Byway". Delaware Department of Transportation. Retrieved January 8, 2012.
- National Highway System: Delaware (PDF) (Map). Federal Highway Administration. 2010. Retrieved February 10, 2012.
- Delaware State Highway Department (1920). Official Road Map (PDF) (Map). Dover: Delaware State Highway Department. Retrieved November 24, 2015.
- Delaware State Highway Department (1924). Official Road Map (PDF) (Map). Dover: Delaware State Highway Department. Retrieved November 24, 2015.
- Delaware State Highway Department (1931). Official Road Map of the State of Delaware (PDF) (Map). Dover: Delaware State Highway Department. Retrieved November 24, 2015.
- Delaware State Highway Department (1932). Official Road Map (PDF) (Map). Dover: Delaware State Highway Department. Retrieved November 24, 2015.
- Delaware State Highway Department; The National Survey Co. (1938). Official Road Map of the State of Delaware (PDF) (Map). Dover: Delaware State Highway Department. Retrieved November 24, 2015.
- Delaware Department of Highways and Transportation (1971). Delaware Highways Official Map (PDF) (Map). Dover: Delaware Department of Highways and Transportation. Retrieved November 24, 2015.
- Delaware Department of Transportation (1990). Official State Map (PDF) (Map). Dover: Delaware Department of Transportation. Retrieved November 24, 2015.
- "Brandywine Valley Scenic Byway - Official Designations". National Scenic Byways Program. Archived from the original on June 6, 2012. Retrieved January 8, 2012.
- Petersen, Nancy (October 9, 2003). "Route 100 loses its way through West Chester". The Philadelphia Inquirer. Retrieved January 20, 2014.
- "Rt. 100 Bridge closed in Elsmere after concrete falls". Philadelphia, PA: WPVI-TV. February 24, 2015. Retrieved March 8, 2015.
- "Emergency Bridge Deck Repairs for the Bridge over East Penn Railroad Will Require a Portion of Route 100/DuPont Road to be Closed". Delaware Department of Transportation. February 24, 2015. Retrieved March 8, 2015.
- Media related to Delaware Route 100 at Wikimedia Commons