State puts 16 bridges on rush inspection listBy PAUL FEELY
New Hampshire Union Leader
August 30. 2017 11:43PM
CONCORD — State transportation officials have targeted 16 red-listed bridges with decks in “poor condition” for inspections, after a large piece of concrete fell from underneath the Route 102 bridge and shattered on Interstate 93 in Londonderry, closing the southbound lanes of the busy highway Monday afternoon.
The New Hampshire Department of Transportation also expects to put out a contract to install protective shielding, similar to what was installed under the Route 102 bridge at Exit 4 off I-93, on all 16 of the bridges it has identified as having “potential issues,” said Bill Boynton, public information officer for NHDOT.
“The piece that fell was not critical to the structure of the bridge,” said Boynton. “It was more of a cosmetic piece underneath it near a beam. Many bridges of that era have similar-type construction. There will be a systematic evaluation of what’s out there with existing bridges that have the same concrete feature, with the information gathered being used to make further decisions. This includes whether there is an issue with other bridges and what if anything additional needs to be done.”
Boynton said all 16 red-listed bridges will be inspected by bridge maintenance crews in the coming weeks, and any loose concrete removed. After a contract to install protective shielding underneath those 16 bridges is put out this fall, Boynton said DOT officials anticipate the work will be complete by the spring of 2018.
The Route 102 bridge over I-93 at Exit 4 in Londonderry was built in 1962. On the red list, it is scheduled to be replaced in 2018 by a new bridge being built nearby.
“This location is an active construction site,” said Boynton. “That includes blasting in the area.”
Debris fell from the Route 102 bridge near Exit 4 and landed in the southbound lane of I-93 in Londonderry around 1:40 p.m. on Monday, breaking into several pieces. While no injuries were reported, several vehicles ran over the debris and officials say at least one had hood damage.
The state designates red-listed bridges as those that are “structurally deficient.” NHDOT inspects all state and local bridges on a regular basis, said Boynton. State bridges are inspected every two years; red-listed bridges are inspected twice a year.
The number of red-listed bridges in the state won’t be getting smaller anytime soon. A draft of the state’s 10-year transportation improvement plan for 2019 to 2028 was unveiled during a public meeting of the Governor’s Advisory Commission on Intermodal Transportation at Keene State College last week.
Senate Bill 38, which allocated money from New Hampshire’s budget surplus to local highway infrastructure projects, redefined red-listed bridges earlier this year to include only bridges given a “poor” rating or below on the national bridge index. Previously, bridges given a “fair” rating were listed.
According to the DOT, there are 140 state-owned bridges and 254 municipal bridges across New Hampshire that fall under the revised definition.
SB 38 also provided an additional $6.8 million in state aid for municipal bridges.
The 10-year plan would address 135 of the 140 state-owned red-list bridges in the state by 2028. On average, 22 bridges are added to the list annually, with 242 projected to be added to the list between 2019 to 2028, according to the report.
NHDOT’s red-list bridges
|These 16 bridges will be inspected for concrete problems in the next few weeks, according to the state Department of Transportation.|
|Amherst||NH 122, Main Street over NH 101|
|Bow||I-89 over South Street|
|Concord||Delta Drive over I-93,US 4|
|Concord||US 202 over NHRR & Constitution Avenue|
|Concord||I-93 SB on-ramp over NHRR & Constitution Ave.|
|Concord||I-393,US 4,US 202 / I-93|
|Concord||I-393,US 4,US 202 over Fort Eddy Road|
|Gilford||US 3 & NH 11 over US 3 & NH 11|
|Lebanon||I-89 NB over US 4 & NH 10 (Exit 19)|
|Lebanon||I-89 SB over US 4 & NH 10 (Exit 19)|
|Lebanon||Mascoma Street over I-89 & NH 10|
|Londonderry||NH 102 over I-93|
|Manchester||Huse Road over I-293 & NH 101|
|Merrimack||Baboosic Road over F.E. Everett Turnpike|
|Merrimack||Wire Road over F.E. Everett Turnpike|
|Warner||NH 103 over I-89 NB|