Bridge construction meets the challenge, earns achievement award
For the New Jersey Department of Transportation (NJDOT),
replacing a deteriorated drawbridge built in 1922 resulted not only in a
gleaming new structure, but in a project distinguished by innovative design
features and a commitment to quality. This commitment was honored with the
National Partnership for Highway Quality’s (NPHQ) 2003 National
Achievement Award. NPHQ brings together state, federal and highway industry
leaders to encourage the use of quality practices that will improve safety and
service for highway users. Members include the Federal Highway Administration,
the American Association of State Highway & Transportation Officials, the
American Public Works Association, the Foundation for Pavement Preservation,
the National Institute for Certification in Engineering Technologies and a
number of roadway construction trade associations.
NJDOT, J.H. Reid General Contractor and Parsons
Brinckerhoff-FG Inc. faced the challenge of replacing the 250-ft drawbridge
with a five-span, 500-ft bridge. The new U.S. Rte. 9 Bridge over Nacote Creek
in Atlantic County, N.J., has a 25-ft vertical clearance and two new approach
roadways. The new approaches were raised and realigned to correct and upgrade
the bridge’s vertical geometry, improve sight distance and eliminate an
existing dip in the roadway.
From the beginning, interaction with the community was
vital. During the early stages of project development, numerous community
meetings were held. NJDOT also took many steps to alleviate community concerns
about the initiative. For example, because traffic congestion was a major
concern, a detour plan was designed that would have the least disruption to the
community. The new bridge also was designed with visual enhancements that would
fit in with the historic aesthetics of the area.
NJDOT worked with the New Jersey Department of Environmental
Protection to protect the environment surrounding the project area, including
marshes, wetlands and the Edwin B. Forsythe National Wildlife Refuge, and to
lessen or eliminate detrimental effects from the construction. Wetland
mitigation activities, for example, included creating high and low marsh tidal
wetlands and establishing a turtle-nesting habitat for the diamondback terrapin
turtles that inhabit the area.
To achieve a high-quality project, NJDOT also implemented a
number of innovative design features that were a first for the agency. These
features included using the Load and Resistance Factor design method and
high-performance concrete for the bridge beams and the prestressed cylinder
piles that support the pier caps. Nontoxic composite materials were employed
for the bridge’s fender system, which protects the bridge from
collisions. Unlike the traditional chemically treated timber fender system, the
new system will not leak toxins into the water. It also has a longer life
expectancy. Other innovations used by the project were mechanically stabilized
earth (MSE) walls and vibro concrete columns for the approach embankments. The
MSE walls were more economical and could be erected more quickly than
cast-in-place walls. The use of MSE walls also reduced the amount of
encroachment into wetlands in the areas around the abutments.
Throughout the construction process, maintaining quality and
safety was the subject of weekly “Tool Box” meetings held by
project staff, where work activities planned for that week and work-zone safety
measures were discussed.
The bridge opened to traffic on Dec. 18, 2002, nearly two
weeks early, and the final cost exceeded the contract amount by only 0.2%.
Another hallmark of quality is that only two change orders were executed during
construction. In addition, no accidents were reported during the entire time
the project detour route was in effect. NJDOT’s proactive approach to
working with the local community also has paid off, as the new bridge has
received a positive reception from residents and business owners.
The new bridge offers users a safer, smoother and better
ride, while the innovative technologies employed will mean a longer performance
life for the structure.