At a Glance

Cape Town, home to more than 4 million, is in the midst of the worst drought to hit South Africa in more than 100 years.City officials say they will "turn off the tap" in April when dam levels are expected to reach 13.5 percent of capacity.

Amid an extreme drought, officials in Cape Town, South Africa, have increased water restrictions but pushed back "Day Zero," the day the city will cut off water to residents unless drastic measures are taken to decrease usage.

Just a few weeks ago, officials pushed from April 22 to April 12. On Tuesday, the date was moved back to April 16, even as water levels continueto dwindle. The city also reduced the daily usage limit from 23 to 13 gallons in an effort to conserve water.

The city's 4 million residents are in the midst of the worst drought to hit South Africa in more than 100 years, and they're rapidly running out of water. The city said earlier this month on Facebook thatit will "turn off the tap" when dam reserves reach 13.5 percent.

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The situation is dire. Dams supplying the city with usable water , according to thecity of Cape Town. Atweet posted Wednesdaynoted that per day was surpassed by 21 million gallons. Several times a day, the city encourages residents via social media to conserve water.

The South African city is a tourist mecca, and touristsare being reminded of the gravity of the situation , theNew York Timesreported.

"A single flush uses 5 days of drinking water," a sign greets tourists. "Our tapswillrun dry if we don't act now."

To avoid Day Zero, the city has reduced water pressure and banned residents from watering gardens and washing cars. Most public swimming pools are closed, and in February 2017, the city resortedto shaming the top 100 water consumers by releasing their identities to the public.

Last July, Executive Mayor Patricia de Lille to no more than 23 gallons a day, which is roughly equivalent to the amount of in a newer model washing machine, according to the U.S. Geological Survey. A single toilet flush can use up to three gallons of water.

De Lille says she hopesit won't come down to Day Zero, but the city is already planning for that eventuality. Should the city be forced to turn off the taps, will be set up to rationout roughly 6.6 gallonsof water per day per resident.

Cape Town isn't the only city dealing with water issues in a warming world.

The World Wildlife Fund estimatesmay face water shortages by 2025 as droughts become more frequent because of global warming.