This much we know is true.
The majority of Boston, Boston Proper that is, is landfill – more accurately called “in-fill”. Parts of the North End, South End and South Boston (and East Boston) are man-made, as is just about all of the Back Bay.
All of the historic South End and Back Bay homes are built on this in-fill. Developers drove hundreds of wooden piles into the ground of each plot of land, then laid down a foundation, and built on top of it.
The wooden piles remained protected from rot because they were encased in water & mud.
Unfortunately, what has happened is the groundwater level has gone down, exposing the pilings to the elements. This has led to some of the pilings beginning to rotting.
Unlike the theory of global warming, however, just about everyone agrees on the cause(s) of groundwater depletion.
Like a spreading virus, properties in some Boston neighborhoods continue to be afflicted with major structural problems caused by diminishing ground water. Leaks in subsurface structures, such as subways, highway tunnels, and deep basements, drain water from the soil, while above ground, the continued rebuilding of Boston has left the city with fewer unpaved surfaces that allow rainwater to seep back into the ground and recharge ground-water levels.
What to do about the problem is up for debate, especially by those who are facing the financial reality – it can cost $250,000 or more to fix just one building.
Therefore, homeowners, the city, and the state are in a mad dance to determine who should pay for what.
What lies beneath – By Ron DePasquale, The Boston Globe