“Apparently if you ever signed up for NotifyATL notifications you got the alert,” Cavitt said. “Many in the metro area that travel to Atlanta signed up for primarily traffic reasons.”

READ | What to do (and what not to do) during a boil water advisory — 7 tips from CDC experts

Gwinnett sent out a news release later Monday saying its water was safe for all uses. The county wanted to assure people that Atlanta had "mistakenly" sent the boil water advisory to some Gwinnett residents and that the water systems are not connected.

The city of Atlanta did not immediately confirm that it had sent the robocalls.

Of course, some addresses in those counties list Atlanta as their city. But, Cavitt said, “we received hundreds of calls from different parts of the county that were clearly not in the Atlanta mailing area.”

Some DeKalb residents reported receiving robocalls about a boil water county in their area, but county spokesman Andrew Cauthen said DeKalb hasn’t sent notifications about an advisory.

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“We’re not doing a robocall,” Cauthen told The AJC. “So, for someone to get a robocall message they more than likely signed up for a city of Atlanta notification.”

Cauthen said only one person is authorized to send a robocall from DeKalb, and because the county didn’t send the call they have no way of knowing how many residents may have gotten one from the city of Atlanta.

Updated area of the boil water advisory from @ATLWatershed, which includes customers in DeKalb County (middle right side of map). @DeKalbWatershed customers are NOT impacted. https://t.co/1WJ2ZQKvhA — DeKalb County EMA (@DeKalbCountyEMA) December 3, 2018

Toco Hills resident Deborah Beck told The AJC she received a call from Atlanta Watershed Management stating her area was under a boil water advisory.

“I was surprised because we pay DeKalb Watershed Management,” she said. “…It’s very unclear to me. For the moment, I’m boiling water.”

Gwinnett spokesman Joe Sorenson said he didn’t know how many reports they’ve gotten of Gwinnett residents getting the robocalls.

But Gwinnett’s water is fine, he said.

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