College Park Interchange

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College Park Interchange

Maintained by MDOT

Highways in Maryland
State highways - Minor - Former - Turnpikes

The College Park Interchange is the southern end of the segment of Interstate 95 in Maryland between the Baltimore Beltway (I-695) and the Capital Beltway (I-495); it is the point where Interstate 95 and Interstate 495 join with one another within Maryland.

Like its companion in Virginia, the Springfield Interchange, it has required modifications to handle the traffic flows it experiences today.

1 Description
- 1.1 North
- 1.2 West
- 1.3 East
- 1.4 South
2 History
3 Notes
4 See also
5 External links

[edit] Description

[edit] North

Approaching from the north, I-95 splits within the interchange. The four-lane southbound carriageway divides into two separate routes; a two-lane high-speed route that ascends onto a long 50mph flyover, for I-95 through traffic headed for the Inner Loop of the Capital Beltway, and a two-lane exit route that continues along the original mainline into the interchange. The two-lane flyover eventually merges with the three-lane Capital Beltway beyond the US 1 interchange's collector-distributor lane split, forming a five-lane express carriageway that narrows to four lanes beyond the US 1 interchange. The two-lane exit route widens to three lanes and splits, with two lanes diverging away to merge with the Outer Loop of the Capital Beltway, and one lane continuing onward that merges with a one-lane directional ramp from the northbound I-95 through route. This lane splits again into a one-lane cloverleaf ramp that merges with the Inner Loop in advance of the US 1 interchange, providing access to the C-D lanes of that interchange, while the remaining lane enters the Park and Ride at the stump end of the interchange.

[edit] West

Approaching from the west, the four-lane Inner Loop carriageway adds a lane at the MD 650 interchange, becoming five lanes wide. At the interchange, the carriageway splits, with four lanes continuing straight ahead, and the outer lane, along with a new lane from the fourth travel lane, diverging away onto a directional ramp. The ramp splits again within the interchange, with the one-lane connector to the Park and Ride splitting off, and the two-lane ramp curving north to connect with the planned mainline of I-95 within the interchange. These two lanes cross both carriageways of the Beltway and merge with the I-95 northbound through route. Beyond the original split, the Inner Loop splits into a local-express configuration, with three express lanes merging with the two-lane I-95 south flyover and one lane merging with the access ramp from the Park and Ride to form two local lanes, providing access to US 1.

[edit] East

Approaching from the east, the four-lane Outer Loop carriageway widens to six lanes within the US 1 interchange, with the fifth lane coming from the US 1 north on-ramp and the sixth lane coming from the US 1 south on-ramp. Within the interchange, the carriageway splits, with four lanes continuing on the Outer Loop, and the two new lanes, along with a third lane splitting from the fourth travel lane, diverging away to form the I-95 north through route. This ramp splits again, with the one-lane directional ramp curving away to connect to the route into the Park and Ride and the three lane ramp continuing north. Beyond the interchange, the four-lane Outer Loop merges with the one-lane directional ramp from the Park and Ride (which enters on the left), remaining four lanes, then with the two-lane ramp from I-95 south and becomes six lanes as far as the MD 650 interchange, where the first new lane is immediately dropped. Beyond MD 650, the second new lane is dropped.

[edit] South

From the Park and Ride, a motorist is offered three choices: straight ahead to I-95 north, which connects with the two-lane directional ramp from the Outer Loop and uses the four-lane mainline planned for I-95 to connect with the three-lane ramp from the Outer Loop; right to the Inner Loop, which uses the ramp originally planned for that movement, connecting into the US 1 interchange's C-D lanes and segregating traffic from the I-95 southbound flyover's merge; and far right for the Outer Loop, which also uses the ramp planned for that movement. The first-choice route merges with the two-lane ramp from the Outer Loop, narrows to two lanes as it crosses the Beltway, then merges with the three-lane I-95 northbound through route to temporarily form a five-lane carriageway; the outermost lane is later dropped, and the northbound carriageway narrows to four lanes.

[edit] History

The interchange was partially opened, along with the connecting segment of I-95, in 1971, completing I-95 between the Baltimore Beltway and the Capital Beltway. As originally planned, it was designed with the idea that mainline I-95 through traffic would continue straight through the interchange and south into Washington D.C. as the Northeast Freeway, joining the North Central Freeway within D.C. and running south towards the central business district. When the D.C. government canceled its segment of I-95 in 1977, I-95 was rerouted onto the eastern half of the Capital Beltway, which lost its designation as I-495. As a result of this rerouting, the interchange was placed under considerable pressure to cater for a traffic flow that it was not designed to handle.

Originally, travelers from southbound I-95 to the Inner Loop had to traverse the one-lane cloverleaf ramp in the southwest quadrant of the interchange; after exiting the ramp, traffic then had to weave through Inner Loop traffic headed for US 1. This unsafe condition was rectified by November 1986, when the flyover from southbound I-95 to the Inner Loop was constructed for I-95 southbound through traffic; the existing one-lane cloverleaf ramp was retained for access to the new C-D lane on the Inner Loop within the US 1 interchange, to segregate through traffic from southbound I-95 and local traffic for US 1. The stump end of the interchange was also modified into its present configuration, and the Park and Ride was built.

[edit] Notes

According to the Maryland Highway Location Reference, the mainline roadway through the interchange, between I-95 and the Park and Ride, is designated I-95X.
Because of I-95's presence on the Capital Beltway, the exit numbers for I-95 and I-495 both continue to ascend by milepost west and north of this interchange, which is Exit 27 on both I-95 and I-495. Normally I-495's exit numbers would ascend in the opposite direction (as they once did), towards the Woodrow Wilson Bridge.