About two-thirds of the large trees and branches jamming a Mississippi River channel near downtown St. Paul were removed Friday by the city, which contracted with a tugboat operator to free the snarl that grew last week in the wake of heavy rainstorms packing high winds.

Among the debris grabbed out of the river was an extremely large cottonwood tree, one of several mature bluff-line trees swept into the river following the recent storms, city spokesman Brad Meyer said.

Work began about 9 a.m. Friday and was expected to wrap up by 4 p.m., Meyer said, adding it wasn’t yet clear whether the job will extend into next week.

There had been some question as to who should be responsible to breaking up the logjam. Meyer said the city decided to step in because “the debris was threatening infrastructure and our ability to respond to public safety issues. … There was the potential to build up and create major issues if we didn’t respond now.”

City officials had asked the nearby St. Paul Yacht Club to foot part of the cost, which will run an estimated $1,000 per hour of work. The final cost may range from $15,000 to $25,000.

The Yacht Club balked at splitting the bill, but agreed to hold the city and contractor harmless in the event of damage to their property. Yacht Club workers were on hand Friday morning to keep escaping debris away from their boats and slips.

“That took a huge liability concern off the table,” Meyer said.

Once the job is done, St. Paul officials will visit with other public agencies to discuss a cost-sharing arrangement. Several jurisdictions share responsibility for the Mississippi, including the U.S. Coast Guard, the U.S. Army Corps of Engineers and Ramsey County.