The spectacular new Gordie Howe International Bridge spanning the Ontario-Michigan border has captivated audiences as it draws closer to its biggest construction milestone — a moment now arriving as the two halves of the bridge begin to meet over the Detroit River.

With a price tag of $6.4 billion, the colossal engineering project will relieve the congested Detroit-Windsor border crossings with a direct connection between Ontario's Highway 401 and Michigan's I-75 when it opens in 2025.

Even before it opens, the new crossing will also take the crown of the longest cable-stayed bridge in all of North America, with a main span of 853 metres overtaking the current record-holder, the Port Mann Bridge in B.C..

As the Gordie Howe Bridge approaches the six-year anniversary of its June 2018 construction start, the U.S. and Canadian crews working in tandem are about to meet in the centre over the river, with the first signs of a connection now installed.

The bridge team anticipates the connection to be complete later this month, but it won't be as simple of a process as one would imagine.

📷 Temporary bracing pieces have been installed on the #GordieHoweBridge to hold the deck in alignment. It will now appear as if the bridge deck is connected but there are a few more steps. #DeckConnect

Read more here: https://t.co/Q5u7NXT9RR pic.twitter.com/FXJkAQdamv

— Gordie Howe International Bridge (@GordieHoweBrg) June 10, 2024

New photos released by the bridge team reveal that the two sides of the bridge are now technically joined, albeit by temporary bracing being used as part of the connecting process.

The 27th segments of both the U.S. and Canadian sides of the bridge are now in place, leaving just an 11-metre/36-foot gap between the two halves.

The space between this gap is to be closed in by a specialized segment referred to as a mid-span closure. Unlike the 54 combined segments making up the bridge deck, this customized piece requires multiple steps of installation that can last as long as six weeks.

The bridge team has shared a detailed breakdown of how these final structural steps will occur in the coming days and weeks, culminating in the bridge deck's expected meeting before the end of June.

With the final main segments in place, crews are using temporary jacks to move the Canadian side of the bridge deck approximately six inches. While the gap is expected to be in the 11-metre range, there are many factors that can result in a wider or narrower space.

Next, crews must perform a global survey on the whole bridge structure and re-stress stay cables to adjust the two bridge halves' vertical alignment.

A pair of cranes on opposite sides of the connection point will be used for the final installation of the mid-span closure piece, while six temporary bracing pieces (closure beams, wind struts and transverse cranks) are being installed to hold the deck in alignment.

With the first of these bracing pieces now in place, it appears to passersby that the bridge connection is complete, but it's really just getting started.

The sixth step in the installation involves engineers measuring the gap again to ensure a perfect fit for the final piece of the deck. Next, two steel girders bolted to either side of the structure will be used to finalize the alignment.

Once these girders are in place, temporary closure beams and wind struts can be removed, and the final elements of the mid-span closure piece can be put into place.

This portion of the bridge is heavily engineered with nine redundancy girders, a pair of floor beams, a dozen precast panels and a dozen soffit panels, and will not be connected to stay cables as with the previous bridge segments.

Concrete and precast installation will follow the mid-span closure piece installation, along with another global survey on the entire structure and restressing of cables.

Once the cables are stressed, all of the remaining temporary bracing will be removed, along with cranes — marking what is sure to be a celebratory day for the structural completion of the bridge.

While the mid-span closure piece will indeed be the segment that enters the Gordie Howe Bridge into the record books, it will still be quite some time before the bridge is ready for cross-border traffic.

According to the bridge team, "A substantial amount of work is still needed, including the re-stressing of stay cables, post-tensioning of the deck and the installation of electrical, fire suppression, drainage systems, barriers, signage, lighting, deck paving and pavement markings, and completion of the the multi-use path."

These final tasks aren't expected to occur until next year.