implosion and demolition

At 11:59 a.m. on August 28 a half mile stretch of steel beams that supported the old Woodrow Wilson Bridge over Jones Point were detonated in a spectacular event applauded by crowds in two states.

Demolition and removal of the old Woodrow Wilson Bridge began in earnest on July 17, 2006 after all traffic was switched onto the first new bridge. The portion of the old bridge over Jones Point Park in Alexandria, VA was demolished first, as it physically overlays the footprint of the second new Wilson Bridge that is under construction.

Removal of the drawbridge started last summer and is proceeding steadily. The drawbridge leaves are being removed first, followed by the large piers and foundations. The portion of bridge between the drawbridge and Maryland shoreline will be left in place for several months and will be used to store construction equipment and access the second new bridge under construction. Removal of this final portion of old bridge is scheduled for later in 2007.

To prepare for the implosion, the deck of the bridge had to be removed by excavators with jack hammers and hydraulic jaws known as munchers, and hauled away – some larger pieces of the deck were broken into small pieces by on-site crushers before being hauled away.

Once the steel beams were cut, the concrete pier columns are chipped away by excavators with jack hammers. All demolition work, except for detonation of the steel beams, has occurred during daylight hours. Dust is being controlled using water trucks, hoses and street sweepers, while noise is being reduced by using quieter equipment, such as munchers and crushers. In addition, the fabric on the fence along the northern perimeter is serving as a dust and noise barrier. An air quality monitoring program consisting of air quality sampling stations and opacity monitoring by certified inspectors has been implemented. Noise monitoring is also being conducted during active work hours. These programs are verifying low dust and noise levels.

Significant portions of the demolished drawbridge and Maryland approach, including concrete and steel components, are being taken by barge to the Chesapeake Bay to create fish reef.

• For more information see: www.wilsonbridge.com