More than 240,000 gallons of sewage has spilled in Gunpowder Falls State Park as of Monday afternoon after someone vandalized a manhole, Baltimore County public works officials say.

Officials said the sewer overflow was discovered Sunday afternoon near Jennifer Branch — a tributary to the Gunpowder Falls — in a heavily wooded area of the park that is east of Harford Road and south of Gunpowder Falls. A resident alerted the county to the problem, officials said.

Crews have been working to contain the overflow, but the waste is being discharged at a rate of about 10,000 gallons per hour, according to the public works department. Health officials will monitor the water quality in Jennifer Branch and post advisories as necessary.

alisonk@baltsun.com

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