COLUMBUS, Ohio— The Ohio Environmental Protection Agency announced today that it will consider recategorizing Big Darby Creek and Little Darby Creek as Outstanding National Resource Waters — the strongest level of protection under the Clean Water Act.

Earlier this year, the Center for Biological Diversity and its partners submitted a formal request to protect the creeks with this status. Thousands of supporters in Ohio, the Midwest and across the country joined the Center in calling for the designations.

“We need to protect the Big and Little Darby creeks immediately, and I’m happy to hear that Ohio is acknowledging that,” said Will Harlan, a senior scientist at the Center for Biological Diversity. “These two creeks are invaluable hotspots of biological diversity that so many species need to survive. They’re beloved recreational rivers for people too.”

The Big and Little Darby creeks shelter more than 100 species of fish and 44 mussel species. Six of these mussels — rabbitsfoot, rayed bean, northern riffleshell, snuffbox, clubshell and longsolid — are endangered. Freshwater mussels are the most endangered group of animals in North America. Nearly 70% of U.S. freshwater mussels are at risk of extinction.

“The Ohio EPA has taken steps in the right direction to protect Big and Little Darby creeks, and we’re excited to engage with the rulemaking process to advocate for the critical Outstanding National Resource Water designation for Big and Little Darby creeks,” said Chris Tavenor, managing director for democracy policy at the Ohio Environmental Council. “Thousands of Ohioans and others from across the country called for further protections, and the Ohio EPA’s action is in response to the power of their voices.”

Big and Little Darby creeks are already designated National Scenic Rivers because of their outstanding aquatic biodiversity. But sprawling suburban development and pollution from sewage treatment plants have caused steep declines in fish and mussel populations. Big Darby Creek has been named one of the country’s most endangered rivers twice in the past decade.

The Ohio Environmental Council and Darby Creek Association joined the Center in submitting a formal request for Outstanding National Scenic Waters designation, which provides stronger safeguards against new sewage treatment plants and other point sources of pollution.

The groups’ request led to today’s announcement that the Ohio EPA will initiate a rulemaking process for reclassifying Big and Little Darby creeks as part of its triennial water quality standards review.

In addition to protecting critically endangered species and water quality, the Big and Little Darby creeks are beloved recreational destinations that attract more than 1.6 million annual visitors.