Norwich – A 40-foot washout on Corning Road was the most serious damage caused by the weekend’s heavy rain that might have dumped 4 inches of rain on Norwich, Public Works Director Barry Ellison said.

The Yantic River flooded its banks after surpassing the 9-foot flood stage mark, but Ellison said most of the flooding along dozens of roads Saturday night and Sunday was caused by storm drains clogged with felled branches and debris.

The clog on Corning Road occurred about 600 feet from the washout area, but allowed water to rush down the street, gaining velocity as it ripped away the pavement and earth at the edge of the road.

Mohegan Park Road had the deepest flooding, but did not sustain serious damage, Ellison said.

Ellison said he does not yet have a cost estimate for the Corning Road repair.

Minor flooding occurred along the Yantic River. Norwich Public Utilities crews used a backhoe to remove two felled trees at the Sherman Street bridge to prevent them from lodging beneath the bridge where sewer and natural gas lines are located.

Ellison said the rain gauge at the Public Works Department showed the city received 4 inches of rain over the weekend.

c.bessette@theday.com