A longtime Baltimore sewer worker is being investigated for “repugnant” social media posts praising Nazis and denigrating blacks, officials said.

A review of the account on Tuesday that featured a photograph of Crescenzo A. Gizzi — a wastewater inspector for the city Department of Public Works — revealed racist and hateful language toward foreigners, comparisons of African Americans to monkeys and language glorifying Nazis as his preferred “kind of illegal immigrants,” the Baltimore Sun reports.

The account also repeatedly characterized Baltimore and Maryland as a “cesspool” and lobbed insults toward Mayor Bernard “Jack” Young and City Council President Brandon Scott.

“The only German I want to speak is this type of German,” read another post by Gizzi that featured a swastika, the newspaper reports.

The account’s name, photo and handle were changed and set to private after the Sun published a story on the offending tweets believed to have been posted by Gizzi, a Public Works employee since 1998 who earns more than $63,000 annually, according to the paper. He could not be reached for comment Wednesday.

“I’ve asked for an investigation into the hate speech,” City Councilman Zeke Cohen told the newspaper. “I’d like to know whether this individual violated any city policies.”

Cohen, who reported the posts to city officials Tuesday, said he was outraged by the comments’ “blatant racism” and anti-Semitism.

“That type of hate has no place in Baltimore,” he said.

In a statement released Tuesday, officials confirmed that an investigation had been launched, but noted that all city employees have First Amendment rights to “think or believe” whatever they desire.

“The reports in this instance show speech that is repugnant and hurtful to many people, but the Law Department has made it clear that such thoughts are protected,” the statement read.

Still, “standards of behavior” apply to all municipal employees, as well as bans on the use of city equipment not utilized in the best interest of all residents and visitors, department officials said.

“The matter is under careful investigation and if remedial action is found to be necessary, it will be taken promptly,” the statement concluded.

Gizzi’s former account, @cres65gizzi, was taken down Tuesday. He has since been suspended with pay, sources told news website Baltimore Brew, which posted purported screenshots of Gizzi’s previous posts from as recently as June 28.

Department officials had no additional comment Wednesday when reached by The Post and did not confirm or deny reports that Gizzi had been suspended.