The Charles River is getting cleaner.

The Environmental Protection Agency on Wednesday gave the river an ``A-'' for water quality, its highest grade since a cleanup program started nearly two decades ago.

The EPA said in its report card that the river in 2013 was safe for swimming 70 percent of the time and safe for boating 96 percent of the time.

By contrast, the Charles _ once ridiculed for its ``dirty water'' in a popular song _ was deemed safe for swimming and boating only 19 percent and 39 percent of the time respectively in 1995.

Regional EPA administrator Curt Spaulding said people can now use the river for a variety of activities without worrying if they'll get sick.

The report card is based on bacterial sampling done by the Charles River Watershed Association.