NH does second ORT conversion - at Hooksett toll plaza on I-93

August 23, 2012

2012-08-23: New Hampshire DOT has its second open road tolling (ORT) project under way at the Hooksett toll plaza on the I-93 Turnpike north of Manchester. Central toll lanes of the 14 lane plaza are being closed off this week to allow demolition of booths and islands so that 2x2 ORT lanes can be constructed through the center.

Three old toll lanes are being removed each direction in the center to make way for the four ORT lanes - the extra space being needed for shoulder, offsets, and a central barrier.

Two cash toll lanes are being added in each direction on the outside of the old plaza so that on completion there will be six cash/mixed lanes each direction in addition to the two ORT lanes/direction.

Throughput in the old plaza which had 5 cash/mixed lanes and 2 separated E-ZPass lanes was calculated at 5x425veh/hr + 2x1100veh/hr or 2125+ 2200=4325veh/hr/direction.

Bottleneck with three lanes feeding into 4325 veh/hr/direction plaza

This constituted a bottleneck since the highway on each side is 2x3 lanes or about 6,000veh/hr/direction. Congestion has been regular in peakhours weekdays, and at weekends and holidays in the summer when the area gets vacationers and visitors from the south.

New capacity should be 6x425 (2550) cash + 2x1800 (3600) ORT or 6150v/hr total.

That's about a 40% increase and matches the roadway capacity.

Safety should be improved too with clear separation of transponder equipped cars from those that stop to pay.

Routinely 80k transactions/day, average daily 68k

This is a busy toll plaza 25m transactions/ year - average daily 68k with the traffic routinely going over 80k/day on summer weekends.

The project involves some improvements to bridges nearby, an extra lane for a distance southbound and the normal repaving work. The construction contract by local firm RS Audley is for $22.9m. Open road toll equipment costs $1.3m, preliminary and construction engineering and administration costs $2.5m for a constructiion total of $26.7m.

Design and project management is by HNTB. The new toll systems are an extension of work at Hampton with the prime designer Xerox/ACS with Telvent doing the open road lanes.

The open  road tolling uses Idris loops in the concrete pavement and SICK laser scanners overhead to do vehicle detection, tracking and classification in a redundant arrangement, while Kapsch antennas and Badger readers do the E-ZPass transponder data transfers.  Cameras from JAI are positioned for front and rear imaging.

No new right of way was needed and since the project was conducted within a existing toll plaza, environmental permitting costs were minimal. (ELABORATION)

Open road tolling is supposed to start mid-June 2013 and the project is due for completion October 2013.

New Hampshire's first open road toll conversion was on I-95 at Hampton and opened June 2010.

A third ORT toll plaza is in design for the Central or Everett Turnpike US3 at Bedford on the southern outskirts of the Manchester area.

COMMENT: This project will be a big improvement in the level of service for motorists over what they've had to date - much better throughput through the toll plaza, much less time wasted in queues, reduced emissions and fewer accidents. All plus, so far. However the question will remain for many as to whether this ORT+cash isn't a second best solution as compared with going all-electronic and taking cash toll collection right off the road.

Rebuilds of old lane-constrained toll plazas into ORT+cash like this have a capital cost  about three or four times the capital cost of going all-electronic and they also continue the higher operating costs of cash toll collection versus transponder/license plate tolling.

The open road toll lanes also invite motorists without transponders to violate by speeding through the center lanes and those motorists must then be pursued for payment by camera imaging, license plate lookup of owner's name-&-address and billing-by-mail - as in all-electronic tolling.

Supporters of keeping cash collection at the sides (ORT+cash) argue the volumes of image/lookup/mail collection will be less than cashless or AET, and losses from uncollected tolls therefore will be smaller.

Whether any saving there justifies the higher capital and operating costs of ORT+cash seems doubtful.

But NHDOT is one of a number of state tollers, mainly in the northeast, who still shun all-electronic as too radical, and risky, and who see ORT+cash as more prudent and conservative.

Of course there are still tollers reluctant to dispense with gates.


TOLLROADSnews 2012-08-23 ELABORATIONS ADDED: Aug 24 14:00

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