The former Fairmount Water Works in 2020, with the Schuylkill at flood levels

💡 Get Philly smart 💡
with BP’s free daily newsletter

Read the news of the day in less than 10 minutes — not that we’re counting.

💌 Love Philly? Sign up for the free Billy Penn email newsletter to get everything you need to know about Philadelphia, every day.

Tropical Storm Isaias had been tracked for days before its Tuesday sweep across the mid-Atlantic, so it wasn’t a surprise. But Philadelphia felt its effects more intensely than some expected.

No tornado-like funnels whipped down within city limits, as they did in Doylestown, Smyrna, Del., and at the Jersey Shore, and fewer than 5% of Philly PECO customers experienced power outages caused by wind and felled trees, compared to a quarter of residents in Bucks and more than a third in Chester County.

Instead, it was flooding that caused trouble.

Fire Commissioner Adam Thiel, who acts as the city’s director of emergency management, issued a warning at a 1 p.m. briefing, saying, “We expect the Schuylkill will rise 18 feet tonight.” By 6:30 p.m., retired meteorologist Gary Szatkowski was predicting the second-highest surge on record for Philadelphia’s western river, with crests not seen for 150 years.

Residents of Eastwick in Southwest Philadelphia, which is in a flood plain, were told to evacuate if the water level in their homes reached 12 inches — which for several people, it reportedly did. Manayunk’s Main Street turned into a stream, and 69th Street resembled a lake. A dredging barge below the Vine Street Expressway Bridge broke loose from its moorings, prompting SEPTA to suspend all Regional Rail service. Water seeped over the edges of the Schuylkill Banks, submerging parts of the recreation trail.

Floods of this sort are likely to become more common, climatologists warn. Last winter was Philly’s wettest in over a century, according to the National Weather Service, with nine flood warnings issued. The city is even gaming out relocation plans for entire at-risk neighborhoods, like Eastwick and Germantown.

On Tuesday, however, skies had cleared by evening. With the sun shining brightly as it began to dip below the horizon, Billy Penn sent Mark Henninger, one of the city’s most prolific Google Maps photographers, to document the rushing river.

Here are 10 GIFs that capture the look and feel of the fascinating scene.

The drop-off at the Fairmount Dam was reduced to next to nothing.

Rushing water overwhelmed the fish ladder on the western side of the damway.

Good thing there’s a life preserver.

On the east side of the river, behind the Art Museum, the trail was swamped and benches dipped their toes in liquid.

That did not stop a cyclist from grunting their way through. (The duck graciously moved aside.)

Spectators gathered on the Water Works pavilion.

Some of the logs that infamously get stuck on the dam bobbled over its edge, popping up like porpoises.

And then washed up against the Fairmount Water Works.

Behind the dam, Boathouse Row’s water-level storage facilities were fully soaked.

A truly historic weather event — that we hope does not return soon.

Danya Henninger is director of Billy Penn at WHYY, where she oversees the team, all editorial decisions, and all revenue generation — including the...