| Better Bridges
Inventory Shows Slow Bridge Condition
Improvement
Bridge conditions have improved
slightly, according to the Better Roads’ 2003 Bridge Inventory, but
agencies face serious challenges in trying to continue this trend.
by Ruth W. Stidger, Editor-in-Chief
The recently released American Society of Civil Engineers
infrastructure rating confirms Better Roads’ own 2003 Bridge Inventory
findings.
Bridge conditions are in a holding pattern, rating a C on the ASCE
Progress Report Card and improving only marginally in our own 2003 study.
A look at creeping improvement shows that the percent of structurally
deficient or functionally obsolete bridges went from 29% in 1998 to 27.5%
in 2000 to 25.8% or 153,420 bridges this year.
Bridges evaluated are 20 feet or more in length. A functionally
obsolete bridge has older design features and can’t accommodate current
traffic volumes, vehicle sizes, and weights.
Structurally deficient bridges are closed or are weight and/or speed
restricted.
Deficient or obsolete bridges contribute greatly to congestion. And
congestion leads to another poor ASCE grade — our nation’s roads were
given a D+ on the ASCE 2003 Progress Report Card.
State report cards
Wisconsin and Kentucky infrastructure report cards were released in
September along with the nationwide ASCE report.
Wisconsin’s bridges rated a B-. About 20% of the state’s bridges
need replacement or rehabilitation, the report says, showing a significant
improvement over the past 20 years.
Even so, funding beyond current levels will be needed to continue
reducing the backlog of deficient Wisconsin bridges, the report states.
Kentucky’s bridges received a C- rating. About 31% of the state’s
bridges are structurally deficient or functionally obsolete. This figure
shows real progress compared to the 36% a decade ago.
Available funding won’t pay to continue the trend, though, and new
resources are needed.
Money, money, money
One hundred percent of state department of transportation bridge
engineers responding to a Better Roads Bridge Inventory Editorial Survey
said funding availability is their greatest challenge in lowering their
rate of deficient bridges.
“Additional funds are needed for both construction contracts and
maintenance activities,” warns Jim Pierce, bridge management at the
Minnesota Bridge and Structures Division.
Increasing traffic outpaces bridge capacity in many parts of the
country, and this is so in many parts of Florida, says DOT Engineer of
Structure Maintenance John Harris. Increased funding is needed.
Some engineers dream of a long-term rehab and replacement plan, and the
money to finance it.
“Like many western states, Utah is experiencing rapid growth along
with an aging of its infrastructure,” says Utah DOT Deputy Bridge
Engineer Dave Eixenberger. “Our greatest challenge is balancing the
needs between the remaining structural life of a bridge and its remaining
functional life (typically traffic driven). Uncertainty in funding further
complicates the situation. However, recent efforts in Asset Management are
giving us better planning tools to accomplish this task.”
In Alabama, Assistant State Maintenance Engineer of Bridges George
Conner would like to see increased state funding for bridge maintenance.
Bill Dittrich, inspection engineer at the Indiana Department of
Transportation, says counties especially need more funding for bridge
work.
Ties to federal money and the accompanying requirements can lengthen
county projects, for example.
Damage control
Before you can control damage, you need to pinpoint its main causes.
Better Roads survey results show that 61% of responding department of
transportation engineers cite bridge age as a major factor in bridge
damage.
Corrosion was given as a cause of damage by 48% of survey respondents.
More than a third — 35% — said more traffic than the bridge was
designed to carry caused damage or obsolescence.
Environmentally speaking
Do environmental restrictions affect how well an agency performs in
replacing or repairing bridges. Yes, replied 56% of Better Roads survey
respondents.
In Alaska, Chief Bridge Engineer Richard Pratt says that in-winter work
permits are hard to get, limiting the already-short Alaskan construction
season.
Air-conformity restrictions can cause problems when it’s necessary to
build a bigger bridge than the structure it’s replacing, says Utah’s
Dave Eixenberger.
Others see environmental restrictions as a nuisance at best — one
that extends the permitting process for plan development and adds to
costs.
“Environmental issues have been increasing design and construction
costs of all structures,” says South Dakota DOT Bridge
Inventory/Inspection Engineer Tracy M. Painter.
Local bridges are most likely to face environmental restriction
problems, says Indiana’s Bill Dittrich. “Historical aspects seem to be
more of a problem for local bridges,” he says.
What’s ahead?
Will states be able to lower their rates of deficient bridges in 2004?
Yes, replied 57% of respondents.
At the Massachusetts Highway Department, Bridge Engineer Alexander
Bardow says that the DOT expects to receive more money in 2004, which will
let them do more preservation and other bridge work.
In Arkansas, State Highway Transportation Department Bridge Engineer
Phil Brand says that they will replace several deficient Interstate
bridges as the fourth year of their five-year Interstate Rehabilitation
Program. This program is in addition to the state’s normal bridge
replacement program.
The truth is, though, that these engineers are among the exceptions
with their plans and careful figuring.
Many states don’t have the money or an adequate plan to decrease the
numbers of deficient bridges.
Until this fact changes, we can expect more mediocre grades from the
ASCE and from the drivers on our roads who must deal with lost time and
other problems often stemming from inadequate bridges.
About Better Roads Bridge Inventory
Every year, Better Roads researchers conduct an inventory of bridge
conditions, including measurement of structurally deficient or
functionally obsolete bridges.
The real significance of this inventory is its timeliness. It presents
current data and precedes similar governmental statistics release by about
a year.
Click Here for
2003 Bridge Inventory Page
Reprinted from Better Roads Magazine
November 2003 |
