Paris’ mayor hopped into the Seine and walked away clean … a huge relief to her ’cause tons of people said they were going to relieve themselves in the river to protest.

Mayor Anne Hidalgo jumped into the world-famous river for a quick dip to show her fellow Parisians the Seine’s clean enough to host open-air swim events and opening ceremonies for the Olympics.

Check out the pics … Hidalgo’s doing her best Katie Ledecky impression as she works her way across the choppy river water in her wetsuit — followed closely by a couple other top Paris officials.

Hidalgo told the assembled media the water’s nice and refreshing … and, most importantly, totally clean for the Olympics which kick off next Friday — good news since French protesters threatened to turn the river into their personal toilet last month.

ICYMI … after Hidalgo and French President Emmanuel Macron — who didn’t attend the swim — offered to swim in the river to prove it was safe enough for athletes, protesters said they planned a defecation demonstration — saying they’d take dumps in the river to stick it to their politicians.

In fact, a website showed French people outside Paris when to poop in the river so their “gifts” would reach the politicians in time and the hashtag “jechiedanslaSeine” — “I’m pooping in the Seine” — trended on X. Hidalgo ended up delaying her swim because of recent snap elections in the country … though we imagine the fecal fanatics didn’t help.

BTW … a monitoring group called Eau de Paris has been testing the water for months and recently claimed there was an unsafe amount of E.coli present — hence the pol’s plunge. NBC News reports these levels have improved since they were first reported in early June.