SAN FRANCISCO (CBS SF) — California’s severe drought is taking a serious toll on San Francisco’s aging sewer system.

Some of the city’s 1,000 miles of sewer pipes are more than 100 years old, among the first installed after the Gold Rush.

The waste was getting dumped into the streets, the streets were getting all muddy, and they thought, let’s do something about that. So, they built these pipes,” SFPUC Assistant General Manager Tommy Moala said.

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Few things in America have lasted 150 years. San Francisco’s sewer system is a working relic but one that works

You might think that the drought would give the sewer system a break, with not as much water going through it. But, while San Franciscans are sending less water down the drain because of conservation, the same, or more sewage is being sent through the system that isn’t being drained as well as before.

“It’s an organic material. It breaks down. It creates hydrogen sulfide. That eats up the concrete in the pipes if it sits there long enough,” Moala said.

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With thousands of people moving into San Francisco, the city’s infrastructure continues to be taxed, no more so than the sewer system. But, sewer workers say they’ll do their best. It’s their duty.