Musk claims the tunnels could ease traffic and "be an example to the world," but experts caution that underground work in Miami is expensive and unpredictable.

In "yet another example of Musk’s perpetual grift of making empty promises to city leaders," writes Alissa Walker, the Tesla CEO is floating the idea of building car tunnels under the city of Miami through his tunnel-digging subsidiary, the Boring Company. Critics question the efficacy of underground tunnels in a city known as "the sinkhole capital of the United States," pointing to the "astronomical" costs of the rare few tunnels that have been built in the city. A Port of Miami tunnel that runs for less than a mile through a shallow channel cost roughly $1 billion to build, and it's unclear "whether or not the Boring Company has truly been able to cut tunneling costs."
Cost aside, another major issue facing any underground projects in Miami will be legal liability and the highly unpredictable effects of digging tunnels through unstable ground. "The ground beneath Miami is a highly dissolvable limestone karst that’s filled with cavities and caverns just like the sea floor," writes Walker, making it difficult to predict how a tunnel might affect the land and buildings above it. "Because part of the issue with the changing of the water table is that it won’t be a direct cause and effect — 30 blocks away is what is going to sink," says Mika McKinnon, a field geophysicist and disaster researcher, questioning Musk's plans for assessing legal liability. "This is not a feasible project without sinkholes, so what will they do when they get sued?"
McKinnon warns that investing in Miami's infrastructure may also be a lost cause in the long term thanks to the ravaging effects of climate change. "By 2100 it’s estimated that a large portion of Miami-Dade County will be rendered uninhabitable by up to five feet of rising ocean" and close to a million residents will face displacement. "It’s a lost city. It’s a zombie city. Buying coastal property in Miami is like throwing your money into the ocean."
FULL STORY: Elon Musk’s Plan to Dig Car Tunnels Under Miami Is Filled With Holes

New York Governor Advances Housing Plan Amid Stiff Suburban Opposition
Governor Kathy Hochul’s ambitious proposal to create more housing has once again run into a brick wall of opposition in New York’s enormous suburbs, especially on Long Island. This year, however, the wall may have some cracks.

A Serious Critique of Congestion Costs and Induced Vehicle Travel Impacts
Some highway advocates continue to claim that roadway expansions are justified to reduce traffic congestion. That's not what the research shows. It's time to stop obsessing over congestion and instead strive for efficient accessibility.

Rethinking the Role of Parking in the American City
In cities big and small, the tide is turning against sprawling parking lots, car-centric development, and minimum parking mandates.

Mapping Sidewalks for Improved Connectivity
A new tool uses aerial image recognition to map a city’s sidewalks and crosswalks. Its developers hope it will aid in creating a more comprehensive understanding of pedestrian networks and where improvements are needed.

Long Beach Residents Oppose Proposed Homeless Services Hub Near Rail Terminus
L.A. Metro’s “end-of-the-line” policy forces people experiencing homeless off transit every night at the same time and location. A proposed hub would provide services a few stops before the end of the line in Long Beach.

The Nation's Most Advanced Secessionist Movement
Legislation supporting the Greater Idaho Movement, which would annex over half of neighboring Oregon, has advanced in the Idaho legislature.
City of Greenville
City of Greenville
Resource Assistance for Rural Environments (RARE) AmeriCorps Program
HUD's Office of Policy Development and Research
HUD's Office of Policy Development and Research
HUD's Office of Policy Development and Research
City of Spearfish
City of Lomita
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.