Salt water damage is expected to damage the fragile, ancient electrical and switching systems of the New York City subway system. The Wall Street Journal published examples of some ways that salt water can damage the subway system :
Salt can eat at motors, metal fasteners and the electronic parts, some many decades old, that keep the system running. Salt water, and the deposits it leaves behind, degrades the relays that run the signal system, preventing train collisions.
Salt water also conducts electricity, which can exacerbate damage to signals if the system isn't powered down before a flood.
But the engineering risks don't just exist for the New York City subway system, but also to the construction materials of buildings, which were exposed to storm surge flooding.
Construction materials made of iron or steel that are exposed to water will rust and alter its shape and size. Building interiors, especially basements, when exposed to water, must be dried, otherwise constructions materials, such as metal fasteners or iron or steel beams, may continue to corrode long after the storm surge flooding subsides. If long-term moisture continues untreated, or if the ground becomes over-saturated by salt water, creating , the oxidation and rusting may cause construction materials made of iron and steel to fail.
Just like consumer affairs agencies advise drivers to avoid buying flood-damaged cars, what is the New York City Department of Buildings doing to secure the integrity of buildings and construction sites, which were exposed to the corrosive salt water storm surge flooding from Hurricane Sandy ?
