Thursday, February 18, 2016

Update on Suicide Deterrent Net Construction Project

The Golden Gate Bridge, Highway and Transportation District (District) would like to share the following updates on the Suicide Deterrent Net Construction Project. Attached is an image of a small sample of the steel net material.

The construction bidding period has been extended two months in order to revise technical specifications, such as ensuring that American-made steel is used for the construction. The bid opening date will move from March 8th to May 3rd, 2016. The District anticipates awarding the contract in the summer of 2016 and expects construction to be complete in about four years.

For the past three months, the District has received interest from many potential bidders, who have asked more than two hundred questions about the suicide deterrent project’s specifications. Many of these have been excellent questions which take more District time and resources to answer than originally expected. These answers will provide bidders with specifications on the types of materials they’ll source and price, so they can submit the most competitive bids. As this net and its installation are unique in the world, there are no quick and easy answers. The suicide deterrent project will be the first large-scale horizontal net installation on a major bridge in the United States. At 385,000 square feet, it will be almost the size of 7 football fields, suspended 220 feet in the air above the Bay.

As is typical of a bidding period, the District has chosen to modify some of the original specifications provided by the design consultant. One example of these modifications can be found in the type of steel the District wants to use to build the net. The original specifications called for a special type of steel that cannot be manufactured in America in sufficient quantities and has not been extensively tested in salt-water corrosive environments, such as the one that exists at the Golden Gate Bridge. The District has chosen an alternative: a high quality, marine-grade stainless steel which can be fully manufactured in America. In addition to staying compliant with the federal “Buy America” requirements so that taxpayer monies support American jobs, this decision also allows us to continue our tradition of using American-made steel. All of the steel on the Bridge, from the first beam to the recent retrofit projects, has been manufactured in the United States. The image below shows an example of the proposed suicide deterrent net material. The frame is not a part of the design.

Suicide Deterrent Sample - February 2016

Changes will be issued to the construction bid documents after obtaining approval from the Federal Highway Administration. Federal Highway Sacramento office staff has been extremely supportive and helpful.

“This project is the first of its kind, and there are many technical questions that need careful consideration,” says Ewa Bauer, Chief Engineer for the Golden Gate Bridge. “The Bridge is known for not only its beauty, but also its magnificent quality. We’re moving as quickly as we can toward building the deterrent, but we will not gloss over critical structural details in favor of speed. We will do this right.”

The Suicide Deterrent project is estimated to cost about $76 million dollars. The net will be manufactured off site, and installation will begin on the east side. The deterrent will consist of a stainless steel net, installed about 20 feet down from the main Bridge roadway, extending 20 feet out, with a slight raise on the outer edge. The net will be installed along both sides of the Bridge, running 1.7 miles in each direction. It will be constructed to have minimal visual impact, with 90% transparency.