The city of Charleston deployed three portable drainage pumps Tuesday morning to the most flooded areas downtown, and at least two of them were expected to pump out water well into the night and possibly longer.

Colonial Lake and its surrounding streets remained mostly under water early in the day, even with low tide coming at 7 a.m. By noon, some streets began to resurface as one pump channeled water from the lake into a storm drain at Moultrie Playground park across Ashley Avenue.

Other downtown pumps were stationed at Poulnot Lane nearby, and at the Low Battery at Rutledge Avenue and Murray Boulevard. In West Ashley, one was set up at Wespanee Drive in the Old Towne area.

These pumps feature flexible pipelines and are powered by a generator; they suck up water from one end and spit it out the other. Those with 6-inch-wide pipes are designed to move 2,200 gallons of water per minute, according to the city's engineers.

Michael Metzler, deputy director of operations for the city's Public Service Department, said he didn't know exactly how long the pumps would remain on the job. He estimated it would take at least another day.

Colonial Lake is connected with the Ashley River through an underground tunnel, but its gate was shut since before the storm to keep rising water from flowing in during the storm and the rising tide. The gate will be reopened at low tide in a day or two, but as of Tuesday, there was too much standing water for the lake to drain on its own before another high tide came.

Tropical Storm Irma's wide bands of wind and rain on Monday created a nearly 10-foot high tide in Charleston as the storm moved through Florida and Georgia roughly 200 miles away. 

With the sea level 4 feet higher than usual, the Atlantic Ocean poured in over the walls of the battery, inundating the southern half of the peninsula. 

City Parks Director Jason Kronsberg said the city actually drained some of the water from Colonial Lake before the storm came, but it couldn't prevent flooding from that much storm surge.

"It came across Lockwood, across the Low and High Battery, and filled in the entire lower peninsula from the Cooper River to the Ashley River," he said. 

Chris Hitopoulos, whose Ashley Avenue home overlooks the lake, watched Monday as the water rose and flooded her basement to almost knee-deep for the third time in two years. 

The last time it happened was during Hurricane Matthew in October 2016.

Months earlier, the Charleston Parks Conservancy and the city completed a $5.9 million renovation of Colonial Lake, which included the installation of a new tidal gate.

Hitopoulos said she thought the flooding from Matthew and Irma must be related to some design flaw in the lake's renovation. "There's something wrong with it," she said. "We never flooded before the renovations."

But Kronsberg said the flooding there has nothing to do with Colonial Lake. 

During Matthew, the area didn't drain properly because the drainage valve nearby on Rutledge Avenue malfunctioned and didn't release storm water the way it was designed to. This time, the whole drainage system was overwhelmed because the storm surge was 8 inches higher than it was during Matthew.

"This would've happened before the renovation or after the renovation the same way," Kronsberg said. "Two of the most significant flooding events in the last 50 years just happened to happen in the last 24 months." 

At a press conference Tuesday, Mayor John Tecklenburg said the Church Creek Drainage Basin in West Ashley also experienced significant flooding. The city has a building moratorium in place until November while engineers study the area's drainage problems. 

"Apparently, this is another example of why that needs attention," Tecklenburg said. 

Of the 111 roads closed due to flooding at the height of the storm Monday, about 17 were still closed around 5 p.m. Tuesday. An updated list can be found online at gis.charleston-sc.gov/road-closures.

As for other damage across the city, Kronsberg said Irma didn't appear to have left as much debris in its wake as Hurricane Matthew did last year, but crews are still assessing it.

Other announcements made Tuesday:

  • Garbage collection is on a one-day delay for Daniel Island, Johns Island and the portion of West Ashley outside Interstate 526. Other areas are on a two-day delay. 
  • Anyone who stored their vehicles for free in city parking garages must move them by 7 a.m. Wednesday to avoid being charged the usual parking fees.

 

Reach Abigail Darlington at 843-937-5906 and follow her on Twitter @A_Big_Gail.

Abigail Darlington is a local government reporter focusing primarily on the City of Charleston. She previously covered local arts & entertainment, technology, innovation, tourism and retail for the Post and Courier.