VANCOUVER -- Those hoping to use the Pattullo Bridge overnight this weekend will need to take a different route as testing is conducted on a new early warning system.

TransLink said the 83-year-old bridge linking New Westminster and Surrey will be closed Friday and Saturday nights from 9 p.m. to 5 a.m.

During the closures, officials will test a recently-installed early seismic warning and wind monitoring system. 

"The system's sensors are designed to detect early warning signs of a significant high wind or seismic event," TransLink said on its website. "Upon detection, traffic control gates, similar to those at railway crossings, will block the bridge entrances."

The new system will also use warning lights and digital bridge closure signs. 

After successful testing, the system will be ready for use. 

During the closures, drivers are encouraged to use either the Port Mann or Alex Fraser bridges instead. The N19 bus will be rerouted over the Queensborough Bridge. 

"Affected customers should plan for an additional 30 minutes of travel time. Emergency vehicles will be able to cross the bridge in both directions at all times," TransLink said. 

"We thank bridge users and neighbours for their patience while we work to maintain the safety and functionality of the Pattullo Bridge until its replacement."