New York City’s Metropolitan Transportation Authority will shut down the Canarsie tunnel, which connects Manhattan and Brooklyn, for 18 months starting in 2019, officials announced on Monday.

An alternative method of three years of partial closure was also considered, but in the end, the extensive damage from Hurricane Sandy in 2012 proved too much and transit leaders opted for a total shutdown.

“It really came down to our wanting to pick an option that minimized inconvenience to the customer,” Veronique Hakim, president of New York City Transit, told the New York Times.

Angsty thinkpieces about how people will move between trendy Williamsburg, Brooklyn and Manhattan have circulated without delays since construction plans were announced in January. Partial service would keep the wheels rolling, but would reduce service by around 80 percent. Shut down the train entirely, and hundreds of thousands of daily commuters have one less option for getting on and off work island (Manhattan) each morning.

Infrastructure isn’t sexy, and improvements to infrastructure take an unbelievably long time. It’s a cliche driven by a sad, sad truth. When it came down to the decision to power through what needs to be fixed in the Canarsie Tunnel rather than patch it up little by little, it all comes down to the facts and figures.

225,000 riders each weekday

Canarsie Tunnel is an important line linking a huge population. New residential buildings and the gentrification of Williamsburg that started to pick up in 2005 exacerbated the problem. Now, the L line is the 10th largest subway system by use in North America, just behind the entire BART line in San Francisco.

11. 50,000 riders

That’s how many riders take the L train from 8th Avenue to 1st Avenue in Manhattan. That whole section won’t work for the entire 18 months of L train construction. Better buy some walking shoes.

10. 236 percent

The percent increase of riders since 1990. For some perspective: The entire population of the United States increased 21 percent in the same time period, and only 16 percent in New York City.

9. 7 million gallons of water

That’s how many gallons flooded into Canarsie Tunnel during Hurricane Sandy. It took 10 days for the corrosive water to be drained, but salt and silt remained like a horde of passengers crowding a delayed train car. Sure, it’s still safe for commuters now, but who knows how long that will last.

8. 1924

The Canarsie Tunnel is 92 years old and was pre-power tool. It’s seen the Great Depression, World War II, Watergate, the invention of the iPhone. Concrete starts to get a little crumbly under the weight of history (and the East River).

7. One in five passengers

The estimated number of people who would be able to successfully use the L train for three years if the MTA had chosen partial closure instead of full closure.

6. 1.4 miles

The length of the cast iron and concrete Canarsie Tunnel.

5. 271,500 feet

The most crucial damage was done to the concrete cable ducts inside the tunnel. The ducts held all of the wiring that runs the trains, and the damage caused irreparable damage. There is simply no way to patch it up, and it will all have to be ripped out and replaced.

4. Three days per week

The MTA couldn’t do the repairs on the weekend and during nights because of the silica dust that gets kicked up while drilling through the concrete. According to an informational video put out by the MTA, weekend construction would close the tunnel until Tuesday or Wednesday because crews would then have to do silica cleanup.

3. $800 million

The amount that the tunnel repairs will cost, the New York Times reports.

2. 10 percent

Thanks to improvements to stations, primarily at the 1st Avenue and Bedford stations, capacity will increase by 10 percent.

1. Unlimited

The amount of commuter complaints from the people who make up those 225,000 riders.

Photos via MTA (1, 2)