Modern wonder: NYC’s water system

Here is a look at the vast system that keeps pumping clean water flowing in New York City:

The pipes that carry this life-giving force are largely invisible to New York’s thirsty masses. (Here’s a great map.) The system includes 19 reservoirs nestled in the rolling hills and mountains, draining a sprawling 1.2 million-acre watershed; three controlled lakes; 300 miles of underground thruways, including one that burrows 1,100 feet underneath the Hudson River; and thousands of miles of thin pipe under New York’s streets. Together, they deliver fresh, potable water to 8.4 million people in New York City and another 1 million people upstate…

The system emerged as a matter of necessity. “New York City developed this water system because it was unlucky,” says Kenneth T. Jackson, the Columbia University historian and authority on New York City. “It couldn’t could take water out of the rivers, because the Hudson is salty all the way up to Poughkeepsie.” In the 18th and early 19th centuries, the city’s growing number of residents relied on wells, water brought in on ships, and spring-fed ponds like the Collect (near what is now Foley Square), which quickly turned into dumping grounds for sewage and garbage. The fetid waters helped spawn the cholera epidemic of 1832, which killed more than 3,500 residents. And the absence of significant water sources in city streets thick with wooden buildings led to a series of disastrous fires. After the Great Fire of 1835, which consumed about 700 structures, municipal leaders were moved to act…

Built at a time when the city’s population stood at about 200,000, the Croton system served well until the early 1900s. By then, New York’s population soared to more than 3 million, thanks to immigration, expansion, and the annexation of the Bronx and Brooklyn. In the early 20th century, the city expanded the system to develop new resources in the Catskills. The Ashokan Reservoir, whose creation required the submerging of seven villages, came into service in 1915. A system of pipes and canals were constructed to ferry water via the Catskill Aqueduct 92 miles to the Kensico and Hillview Reservoirs in Westchester—including a circular tunnel with a diameter of 14 feet that goes 1,100 feet under the Hudson River near West Point. Water Tunnels No. 1 (completed in 1917) and No. 2 (completed in 1937) carried the water from Yonkers into Manhattan. Next came the Delaware system to the city’s northwest. Starting in the 1950s, vast pools of water created by damming tributaries of the Delaware River were fed into new infrastructure, including the Delaware Aqueduct, which at 82 miles is the longest continuous underground water tunnel in the world. Here, again, gravity does the work. The highest reservoirs are about 1,200 feet above sea level. And the volume of water pushing down through the pipes creates an enormous amount of power. Today, Bosch notes, “the pressure is so great that it can take it to the sixth floor of most boroughs without any pumping,” said Bosch.

The 500 miles of fat pipes upstate are augmented by 6,500 miles of narrower underground conduits that run underneath the five boroughs, from the crags of Riverdale to the distant, wave-tossed shores of the Rockaways. From the Hillview Reservoir in Yonkers, right on the Bronx border, pipes plunge a few hundred feet into one of the three massive water tunnels that carry water to the south about 500 feet below ground level. Every 20 blocks or so, vertical tunnels sprout up to feed into trunk water mains, with a diameter of about a foot. Ultimately, they connect to buildings, whose pipes are private property.

It would be really difficult to have the #1 global city without a well-designed water system. Such planning and engineering may not get much attention in explaining New York City’s rise but it certainly had to be present. Interestingly, histories of Chicago tend to note the importance of reversing the flow of the Chicago River so that waste was sent downstream towards the Mississippi rather than into Lake Michigan where it polluted the water supply.

Discovering underground Roman aqueducts

A group of amateurs have been tracing portions of Roman aqueducts hidden from view:

The group, which has been exploring underground Rome since 1996, has completed about 40% of its mission to map the aqueducts.”The famous arched, over-ground aqueducts we see today are just the tip of the iceberg; 95% of the network ran underground,” says Marco Placidi, head of the speleologists group, which is sharing its results with Italy’s culture ministry…

Dropping into the hole, Baldi disappears down the Anio Vetus aqueduct, a 3-foot-wide, 5-foot-high tunnel lined with pristine Roman brickwork. As frogs, spiders and grasshoppers scatter, Baldi reaches a maintenance shaft, complete with good-as-new footholds dug into the bricks that lead up to a narrow opening in the woods 10 feet above. Beyond him, the tunnel vanishes into the darkness…

“We have found Roman dams we didn’t know about, branch lines taking water to waterfalls built in private villas, and even aqueducts driven underneath” streams, Placidi said. “We are able to get up close and [feel we are] right back at the moment the slaves were digging.”

As the article notes, the level of construction here is quite amazing to survive roughly 2,000 years. But, without such underground aqueducts, the city of Rome may not have survived long.

What might happen to these infrastructure marvels? Perhaps they could be turned into tourist opportunities like the tunnels under Paris.