A temporary "pedestrian safety fence" intended to prevent suicides will be installed starting on Sept. 25 on the south side of the George Washington Bridge, announced Monday after a tour of the span by high ranking Port Authority officials.

Installation of the fence on the span's upper-level south sidewalk means it will be temporarily closed to pedestrians and bicyclists for three months, officials said. So far this year, agency "initiatives" have been credited with "intervening in 45 cases where emotionally disturbed people were considering doing themselves harm on the bridge," officials said.

Pedestrians and cyclists will be detoured to the bridge's north sidewalk. Officials said the detour will result in a temporary inconvenience to cyclists, who will have to roll their bikes up a channel adjacent to a staircase or carry them to reach the north sidewalk.

Port Authority engineers developed an "innovative, alternate design" that involves hanging the fencing from the bridge suspender cables which made a temporary fence possible, said Steve Coleman, a Port Authority spokesman.

Previously, a temporary fence would have had to be anchored to the sidewalk, which would require extensive work on the sidewalk to provide a stable fencing structure, he said.

A permanent fence will be installed on the north side of the bridge when its suspender cable ropes are replaced in 2018. When that work is finished and the north walkway reopens, permanent fencing will be installed on the south side when suspender ropes are replaced on that side of the bridge, officials said.

The change followed a tour by recently elected Authority Chairman Kevin O'Toole and Executive Director Rick Cotton, who reviewed the $1.9 billion "Restore the George" program to rebuild and renew key pieces of the 87-year-old span's infrastructure.

Work started on the multi-phase bridge project in 2015. The decision accelerates installation of fencing on the south walkway by four years, according to a 2016 GWB project schedule.

Larry Higgs may be reached at lhiggs@njadvancemedia.com. Follow him on Twitter @commutinglarry. Find NJ.com on Facebook.