Superstorm Sandy exposed a number of vulnerabilities in New York City’s infrastructure and emergency-preparedness systems. One of them had to do with water.

With power out in some sections of the city, the mighty water system showed one of its Achilles heels: Powered mostly by gravity, the system could only bring water to apartments approximately six stories high. Above that, you need power to pump the water, says Rae Zimmerman, professor of planning and public administration at NYU.

That was a minor blip. Imagine a larger threat to the water system — not just that water couldn’t reach your apartment, but that it couldn’t reach the city at all.

Without a reliable connection to upstate reservoirs, New York would quickly become a thirsty, smelly place.

This was what was so disturbing about allegations this week that Mayor Bill de Blasio’s administration was being careless with the funding for a key backup for the city’s water-supply system.
    
The city gets its famously pristine water — approximately a billion gallons a day — from upstate lakes and reservoirs that are so clean and well-protected the water arrives at your tap mostly unfiltered.

The vast majority of New York’s water travels downstate through two tunnels, built in 1917 and 1936, which it has never been possible to shut down, though they are in serious need of repair. Since 1970, the city has tried to build a third conduit to help bring water south — a project that would provide the redundancy necessary to turn off and repair the other tunnels.

In 2013, Mayor Michael Bloomberg announced the activation of the Manhattan section of the new tunnel.

The project still wasn’t done, though: A second phase, bringing water to Brooklyn and Queens, was still under construction. At a news conference announcing the completion of the Manhattan section, Bloomberg suggested that construction would be finished in 2021.

But the city’s DEP commissioner said last year that funding for the construction of the third tunnel had been removed from the city’s preliminary budget, shifted to another priority. This week, a report in The New York Times suggested that the shift in funds was meant in part to keep water-bill rates down.

The mayor’s office denies this, pointing to the small amount of money — $305 million — devoted to the project, which is almost completed and which they say would have little effect on rates, the equation for which is partially dependent on capital needs. The DEP capital budget runs into the billions.

On Wednesday, the mayor said that there had been a “misunderstanding” over what the shifted funding indicated. He blamed the shift on a "budgetary reason” that hadn’t in fact held up work on the tunnel, as design and acquisition work still remained to be done.

Even better, he said the upcoming executive budget would include additional funding to start the final phase of work a year early.
    
The quick turnaround is a welcome acknowledgement of how precious the water system is — it shouldn’t be subject to the short-term shifting of budgets that can characterize other long-term projects (Second Avenue Subway?).

This is an infrastructure project that, though it’s partially a fail safe, is entirely essential.

The leaky water system is a “real concern,” says Sarah Meyland, a water specialist and associate professor at NYIT. She says that New York must have “enough belts and suspenders and backup plans that water is always available” to New York City.

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