How rising groundwater levels due to climate change could damage coastal communities

“The Bay Area is heavily polluted by military exploitation, from Silicon Valley tech tech booms — it has left a lot of bad things behind,” says Kris May, a coastal engineer and meteorologist who founded the Pathways Climate Institute. “And what happens is we often put low-income homes in those areas when they are redeveloped. But they still leave a little pollution on the ground, and the rules were based on groundwater table.”

Now groundwater is rising. And when it does, it fills the soil, releasing pollutants like benzene. The chemicals are very stable, and like air they can find their way easily through the toilet lines and into the house.

This is the result of the rise of the water under only one system — toilets. But it can also affect many others. Poorly covered power lines will shrink; the foundation will begin to move from the pressure. Some fear that earthquake damage may be forced.

How water finds its way

To protect themselves from rising sea levels, cities are using the same tools they have been using for centuries: levees and ocean walls. Boston has presented a 175-mile sea wall project called the Sea Gates Project. Miami has an idea for a $ 6 billion, 20-foot-high seawall. New York has developed its own $ 119 billion, six-mile project called the New York Harbor Storm-Surge Barrier. Homeowners from Florida to California are setting up barriers to sea access. But the basic problem with both approaches is the same: the ocean wall blocks the sea, not the water below.

In some areas, if the surface of the ground is impermeable to water, it may be possible to form cracks in the oceans or on the legs of the floating ground. But then you have some problems left. Remember that water flows into the sea. A barrier that prevents water from rising and seawater will also protect stormwater, say, the recent rain from flooding the oceans.

“If you do not allow water to flow into the sea, then you have to pump it. And this is exactly what the Netherlands has been doing for centuries, “says Rozell of Stony Brook.” San Francisco and Boston — built on wetlands, in garbage dumps, or both.

And while cities may be prepared to follow such a course, not all areas can. “There are so many things you can pump all day and water can’t fall,” says Fletcher of the University of Hawaii.

Remember that groundwater is the water that seeps into the gaps, or pores, in the mud. In some places, such as Miami, “the holes are so large that they drain water off the coast,” says Fletcher. “You can pump as much as you want, and the water just comes out of endless water” —a sea.