Westerly — Work to remove the Bradford Dam on the Pawcatuck River began this week, The Nature Conservancy announced Thursday.

Crews began the project by carving a temporary bypass channel around the dam in preparation for the structure’s removal in July, the conservancy said in a news release. The dam will be replaced with a more natural step-pool design, allowing more fish to swim upriver to their traditional breeding grounds and eliminating the risk of flooding from a catastrophic dam failure, the conservancy said.

Bradford Dam is a 6-foot-tall, 200-foot-wide structure built in the mid-1800s to support a mill on the riverbank. The mill has been idle for many years, and the dam has since fallen into disrepair, losing chunks of rock downstream in several recent major storms. In its current state, the dam restricts the movement of migratory and resident fish and is at risk of failing and causing a major flood during another powerful storm, the conservancy said.

The dam removal is part of an effort to open up the 31-mile-long Pawcatuck River and associated wetlands for migrating American shad, alewife, blueback herring, American eel and sea-run trout. Removal of the dam will improve connectivity for all of these species, many of which have historical breeding grounds that lie farther upstream.

In addition, the step-pool design will include a 10-foot-wide channel allowing canoes and kayaks to pass easily through the area, the conservancy said. It will eliminate an onerous portage for paddlers almost immediately downstream of the popular boat launch at Bradford Landing.

“We’re proud to join with The Nature Conservancy and other partners in restoring our rivers and river systems to better withstand future storms and other environmental and land-use changes,” U.S. Fish and Wildlife Service Northeast Regional Director Wendi Weber said. “Healthy rivers are lifelines for communities in the Northeast — providing recreation, water quality, strong economies and other benefits. By connecting and opening waterways like the Pawcatuck River, we’re helping wildlife thrive and creating more resilient communities for people.”

The $1.8-million project is being overseen by The Nature Conservancy and is supported by $821,000 in federal funding for Hurricane Sandy recovery and resilience projects. The funds are part of a $1.98-million cooperative agreement between the conservancy and the Fish & Wildlife Service for the Pawcatuck River, which included the removal of the White Rock Dam and improvements to the Potter Hill Dam fishway. Additional public funds were provided by the R.I. Department of Environmental Management and the R.I. Coastal and Estuary Habitat Restoration Fund.

The conservancy raised the balance of the project funding from The Champlin Foundation, the Bafflin Foundation, the Horace A. Kimball and S. Ella Kimball Foundation, the Rhode Island Foundation and individual donors.