From an email, unedited:
Below is the latest update on the Lesner Bridge replacement project from Chris Wojtowicz, project manager. If you have any questions or need additional information, please let either Chris or me know and we will be glad to help you.
Enjoy your holiday weekend.
Media and Communications
Department of Public Works
City of Virginia Beach
Summer has officially begun, and – as you have noticed – so has the construction of the replacement Lesner Bridge project. I have spoken or corresponded with many of you over the past few weeks regarding your concerns with the start of this construction work. Based on these discussions, our project team felt that a brief update on the work and our response to the top three concerns might help folks better understand what work is taking place right now.
Below are the top three questions – and answers – that we have been discussing with so many of you:
Q: “Why wasn’t my property included in Pre-Construction Damage Assessment Survey?”
A: Generally, all properties (10) within 200 feet from a source of vibration that could exceed a threshold particle velocity value of 0.5 in/sec between a frequency of 2 and 10 Hz have been included in the contract documents. We refer to the AASHTO Standard Recommended Practice for Evaluation of Transportation-Related Earthborne Vibrations for selecting this threshold particle velocity – which is the level at which a plaster wall MIGHT begin to crack.
If your property was not included in the contract documents as one of those requiring a survey, then your property fell outside of this zone of influence and has an extremely low risk of structural damage from construction related earth related vibrations. That being said, if the City felt that there was any risk of structural damage to a particular property, that property would have been included in the contract documents as requiring both a Pre- and Post-Construction Damage Assessment Survey.
Beyond the expected areas of influence, seismographs – along with horizontal and vertical control points – have been placed so that the project team can monitor these vibrations in real time and make adjustments to the construction methods if necessary. [As a side note, people “sense” or respond to a much broader range of vibration frequencies and intensities than structures. Intrusive vibration levels might concern some folks at much lower intensities than levels considered critical for structures (0.5 inches/sec between 2 and 10 Hz)].
So even though extremely low levels of vibration may be a nuisance to some people and cause one to become concerned about structural damage, there really is very little risk of this damage. All Pre-Construction Damage Assessment Surveys have been completed at this time.
Q: “Why does the Contractor have to work at night? There is so much noise!”
A: The contractor is only performing work at night that requires temporary lane closures on Shore Drive. Since we are in the summer months, daytime lane closures on Shore Drive are not permitted until after September 30th unless an exemption is granted by the Public Works Traffic Engineering Dept. Both stationary and non-stationary noise at night is now being monitored by the City using an Extech Digital Sound Level Meter to assure the Contractor’s compliance with the contract documents.
Q: “Why did the bridge contractor placed a fence at East Stratford Street and Shore Drive? This impedes pedestrians who want to cross Shore Drive from East Stratford Street to get to the beach since the beach access at the boat ramps has been closed.”
A: New storm drainage and a large stormwater management device need to be installed at this corner. This fence and other barriers are required to “safe-up” the work area and the deep excavation that will be performed. The project team has reviewed the pedestrian access concern and will make some minor design changes (such as moving the stormwater management structure further to the east) to better accommodate these pedestrians. The proposed changes are that the pedestrian signals will be un-bagged and a gate will be added to the temporary fence to allow pedestrians access to the existing crosswalk. These changes will be implemented before July 4th.
The work taking place right now on the project involves modifying the approach lanes at both existing bridges in preparation for shifting the lanes of traffic slightly to the south. This lane shift is required in order to make room for the equipment and utilities needed to construct the new westbound bridge. The crane that is out there now on the west side of the bridges will be used in the construction of the first bridge footing and abutment for the new westbound bridge.
Bridge footing construction will likely begin in August 2014 and will progress from west to east. During this time the concrete casting yard, Atlantic Metrocast Inc., in Portsmouth VA will be prepared for production of the pre-cast concrete bridge sections. Placement of the first bridge segments on the new bridge piers/foundations will likely begin in mid-March 2015.
Thank you again for all of your valuable input that helps us move this project along in a safe and responsible manner. Still to come – Lesner Bridge Construction Webpage with live/time lapse construction video.
Enjoy your summer.
Christopher J. Wojtowicz, P.E.
City of Virginia Beach
Department of Public Works
Municipal Center-Bldg 2
2405 Court House Drive
Virginia Beach, VA 23456-9031
Phone: (757) 385-5785
Fax: (757) 385-5668
Note: Photo was not in email but added by the Editor to ensure everyone knows of the challenges using the beloved Lynnhaven Boat Ramp & Beach Facility this coming Holiday Weekend. Be safe people.