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The city’s continuing investigation of the best way that commuter rail traffic can cross the New River has begun to bear some incredible results — results that could reshape the ongoing discussions with state and county officials about the viability of a tunnel instead of a bridge.
First, the city’s consultants at BDO have announced their findings that address concerns previously raised about tunnel construction and future operations. They concluded a tunnel could be built at a third of the cost that other consultants estimated earlier and in a way that would not require the additional expense of forcing nearby property owners to sell their land as they would need to do for a bridge.
Second, the builder and operator of the Port of Miami tunnel has come forward with details of their success, providing an independent and unvarnished analysis of tunneling in South Florida. They have even stated that they would be interested in eventually submitting a proposal for a public-private partnership for a New River tunnel.
While Broward County is moving forward with planning for a high-rise bridge splitting our downtown, these new developments breathe fresh life into the tunnel alternative. During a tour of the Miami tunnel with county leaders, we began seeing new openness to the idea. We hope this cooperative spirit can continue forward.
Here’s what the BDO consultants have told us.
They have drawn up preliminary designs that illustrate a tunnel could be built with no disruption to current Brightline trains or freight traffic. This is of critical importance to both Brightline and the Florida East Coast Railroad.
The tunnel would be shallow at 55 feet deep, thus not requiring substantial digging. Brightline has reviewed the proposed gradient in the proposed tunnel and said that it is acceptable for commuter traffic.
The design keeps the tunnel entirely within the railroad’s existing right-of-way except at the river itself, where it would deviate slightly to avoid the pilings of the existing train bridge. There would be the need to obtain the underground rights to three small portions of property — two are owned by the city and the third is owned by a developer who is willing to work with us because of the substantial impact a bridge would have on his planned project.
Some people have questioned the resiliency of a tunnel given the flooding and heavy rains experienced in the region. But BDO plans for that by installing major flood gates at each portal.
Others question whether there would be vibration during construction that could harm existing structures, but BDO notes that the tunneling technology they propose has been used under highly developed locations such as Chinatown in San Francisco.
BDO’s estimated price tag is $888 million, less than the $3 billion that other consultants suggested. While more than the almost $600 million that the county estimates a bridge would cost, BDO says the difference likely could be made up through new federal infrastructure grant funding.
Also, BDO estimates that the operation and maintenance of the tunnel would cost $2.5 million a year. That’s one-tenth of what other consultants estimated. The Broward Metropolitan Planning Organization now acknowledges that the earlier estimate was very high because those consultants had more unknown factors to consider than BDO did.
Meanwhile, there are the developments with Miami.
A month or so ago, Chris Hodgkins, the head of the concessionaire operating the Miami Tunnel, reached out to my office inviting me to tour the facility in light of our ongoing discussions. I then asked county leaders if they wanted to join me. And they agreed.
The trip was enlightening.
The Miami tunnel was built through a public-private partnership between the Florida Department of Transportation and a consortium of two international firms – Meridiam and Bouygues.
It was the first ever P3 for FDOT and required the consortium to design, finance, build, operate and maintain the port tunnel. The deal has now been used internationally as a model for P3 infrastructure projects.
The project was completed $90 million under its $1 billion price tag and on time. It’s 45 feet wide, almost twice the size that would be required for a train tunnel, and 120 feet deep, far deeper than the New River crossing. You do the math.
Hodgkins noted to the group that the Miami tunnel had to address resiliency concerns similar to the questions raised in Fort Lauderdale. They built flood gates like those that BDO has proposed and have used them multiple times during hurricane warnings.
Some have questioned the viability of tunnel construction in South Florida given the geotechnical dynamics here. But Hodgkins said the Miami tunnel was built through a limestone base similar to that in Fort Lauderdale and that they compensated for its porous nature by inserting polymer into gaps to shore it up.
He also addressed the issue of construction vibrations, agreeing with BDO that the tunneling technology avoids that. He said it was important to his project to avoid vibration so as to both protect structures like the Children’s Museum and not disturb the animals at Jungle Island.
Let’s hope that this progress continues and that we all can agree on a tunnel. We need to protect our vibrant downtown and our historic district and that we do not further divide communities as the train tracks long have.
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