This story is updated from an earlier version.
Some minor flooding was reported late Wednesday and early Thursday along the Cecil County shore of the Susquehanna River below Conowingo Dam, as more than a dozen of the dam’s floodgates were opened Wednesday to handle rising river conditions.
The dam operator, along with state and Cecil County leaders, continued to monitor the risk for flooding downriver along Route 222 north of Port Deposit.
“We’re in contact with all of our local communities and emergency responders,” Deena O’Brien, a spokesperson for the dam’s parent company, Exelon Generation, said Wednesday afternoon.
Fourteen of the dam’s 50 spill gates were opened Wedensday afternoon, but the number of open gates had been reduced to 10 by early Thursday morning as the rising river crested behind the dam Wednesday evening.
Exelon officials expected “to see river flows going down” and to be closing spill gates in the coming days, O’Brien said.
Some some minor impacts from high water was reported, however, in and around Port Deposit.
Route 222 was closed “for a brief period” Wednesday night, but it had reopened as of Thursday morning, Mayor Wayne Tome Sr. said.
Some railroad underpasses in town had been flooded out, with debris left behind but no damage, and there had been high water near Marina Park, according to Tome.
This week’s higher river levels were not related to Hurricane Florence, O’Brien said. Florence is expected to hit the Southeast Thursday and could potentially cause flooding and power outages in Maryland later in the weekend or sometime next week, according to state and local officials.
“We’re watching [Florence], but it’s not going to affect us in the near term,” Tome said. “We’re watching how it tracks when it comes inland.”
Gov. Larry Hogan declared a state of emergency Monday, and Harford County emergency officials began preparations the same day. Residents have been buying water, filling sandbags and making other preparations ahead of the storm.
The Hogan administration monitored conditions south of Conowingo Dam, as the floodgates remained open, as did local officials in Harford and Cecil counties.
The governor urged Marylanders, in a tweet Wednesday, to “heed warnings” and “prepare for the possibility of more rain, which could cause more severe flooding.”
That warning from Hogan was posted along with other updates on the Exelon Generation Twitter feed Wednesday.
Weather conditions that are “most impactful to” Conowingo Dam, which spans the Susquehanna between Cecil and Harford counties, happen in central Pennsylvania, O’Brien said.
“The hurricane is not expected to have any impact in central Pennsylvania, thank goodness, so we’re not expecting a significant event with the hurricane,” she said.
Tome said town and county officials will monitor any impacts from Florence in the Susquehanna River basin.
The region has been saturated by rain during the spring and summer, though — two Harford residents died after being caught in raging floodwaters in Churchville during an Aug. 31 storm.
Exelon Generation has removed more than 1,800 tons of debris from the river so far this year, according to a company statement provided by O’Brien.
The Susquehanna, which flows through New York State, Pennsylvania and Maryland and has a 27,500 square-mile watershed in those states, provides about 90 percent of the fresh water in the upper Chesapeake Bay, The Baltimore Sun reported in August in the wake of tons of debris stacking up behind the dam following record-setting rainfall in July. At least 20 floodgates opened in late July, prompting concerns at the local and state level about the impact on the bay from so much debris and sediment.
“It comes in waves,” O’Brien said of the debris Wednesday. “We were able to get a large portion of the debris that came down in late July. We do have a little bit of debris behind the dam now, that we’re working on as well.”
Ten gates were open as of 8:30 a.m. Thursday, according to the dam’s automated spill condition hotline. The river was flowing at 242,000 cubic feet per second, and the dam operator expects to have eight to 13 gates open in the next eight hours, according to the message.
People can get information by calling the hotline at 1-877-457-2525; conditions are updated every eight hours.