At least, that's not what's going on in this widely circulated photo of a sinkhole filled with bright green ooze.

Here's where we figure out who the real infrastructure geeks are.

Last week, photographer Steven Reitz captured this photo of a sinkhole in Philadelphia that appeared to be filled with a Ghostbusters-esque green ooze. When the image exploded on Reddit, there was naturally some talk about sludge, slime, and pending mutations to the local population.

The explanation, depending on how you feel about wastewater systems, is cooler or less cool. The Philadelphia Water Department, according to NBC 10, uses harmless dyes to trace the connections of sinkholes underground, in an effort to detect their relationship with other underground water deposits. Neon green, obviously, is a particularly visible hue, though the department also uses red and blue.

Anything to get the people interested in water management, right?

Top image by Steven Reitz.

About the Author

Most Popular

  1. Design

    The Rivers of the U.S., Collected Into a Nifty Subway Map

    A designer who spent his youth floating on rafts has conjured up a delightful transit guide to America’s waterways.

  2. Transportation

    Why Some Brits Are Fuming Over London's Crossrail

    A massive new commuter rail project is stoking centuries-old resentment in Britain’s north-south divide.

  3. Transportation

    5 Reasons to Be Wary of Elon Musk's Hyperloop

    High-speed vactrains might be the ticket for a Martian colony. As a practical transit investment for Earth, the technology has a long way to go.

  4. Equity

    Why Some Women Don't Actually Have Privacy Rights

    A law professor explores the reasons why women who need government assistance are forced to divulge intimate details of their lives.

  5. Maps

    U.S. Transportation Funding Is Not Created Equal

    Some states shoulder the lion’s share of state and local road costs; others lean on Uncle Sam.