There is a breathtaking view of the mid-Manhattan skyline, pierced by the Empire State Building, from the 48th floor of the taller of two new copper-clad apartment towers along the East River, just south of the United Nations.

No plutocrat will enjoy it, however. This impressive penthouse aerie is hogged by five emergency generators. The window is already blocked by a bank of electrical switchgear. For the developers, giving up premium space to machinery is insurance against an ominous future: They want tenants in the towers’ 760 apartments to be able to live in their apartments for at least a week, no matter how high floodwaters may reach nor how long the power is out.

“We said: ‘Water is going to come in here. What are we going to do about it?’” explained Simon Koster, a principal in the JDS Development Group, which is building the towers, known as the American Copper Buildings.

JDS is in good company.

Along coastlines and lake shores and riverfronts across the country, tenants and homeowners, regulators and planners, private developers and public institutions are embracing the accumulating evidence of climate change and fortifying buildings and infrastructure against rising sea levels and ever more intense storms.