Science Fair Project Encyclopedia
A jughandle is a type of ramp that changes the way traffic turns left (in right hand traffic). Instead of a standard left turn being made from the left lane, left-turning traffic uses a ramp on the right side of the road. In a standard jughandle, the ramp leaves before the intersection, and left-turning traffic turns left off of it rather than the through road. Right turns are also made using the jughandle. In a reverse jughandle, the ramp leaves after the intersection, and left-turning traffic loops aroung to the right and merges with the crossroad before the intersection.
Occasionally a backwards jughandle is used, where traffic on the side road cannot turn left at the intersection but turns left after it, merging with the main road. This is most often used for U-turns where a normal jughandle cannot be constructed; traffic turns left off the main road onto the ramp.
Occasionally, a jughandle is removed if turning traffic is too heavy (see Disadvantages). In at least one case (New Jersey State Highway 36 at New Jersey State Highway 71), the jughandle was kept for U-turns, but left turns are made from a left-turn lane.
The first mention of jughandles in the New York Times is on June 14, 1959, referring to jughandles having been built on US 46 in Montville, US 22 between North Plainfield and Bound Brook, and Route 35 at Monmouth Park Racetrack.
On New Jersey State Highways and Pennsylvania State Highways , a white sign is placed before a jughandle or at the beginning of a stretch of jughandles saying ALL TURNS FROM RIGHT LANE. Each jughandle is marked with a white plate below the standard green sign, saying ALL TURNS, or U AND LEFT TURNS in the case of a reverse jughandle.
On locally maintained roads, and in other states, jughandle signage is usually haphazard and confusing.
- Safety — eliminates many collisions in the intersection
- Reduces traffic light phases — increases green time for through traffic, and prevents backups in left-turn lanes (which may be replaced with backups on jughandles, but this doesn't usually affect the main road)
- Lane usage — the left lane is for passing only, as all turns are made from the right lane
- U-turns are possible without making a tight turn
- Backups on the ramp — the end of the jughandle ramp is not normally controlled by a traffic light, so it may be hard to make a left turn if there is a lot of traffic approaching the intersection, or to get into the left lane to make a U-turn from a reverse jughandle
- Inconsistent — not all intersections use the system, so drivers approaching an unfamiliar intersection don't necessarily know whether to be in right or left lane
- Confusing — since the scheme is rare outside of the northeast U.S., it is confusing to visitors, who expect to be able to turn left from the left lane
- Requires more land — Fewer lanes are needed at the intersection, but the jughandle ramp itself requires a lot more land, unless it uses existing roads or is shoehorned between buildings
- Users of a reverse jughandle have to go through the intersection twice
- 'Jughandle' Cuts Highway Tie-ups, New York Times, January 2, 1960, page 15
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