NORTH KINGSTOWN, R.I. (WPRI) — Every year, thousands of river herring make the 6.3-mile journey up the Narrow River to Carrs Pond in North Kingstown.

To get to their final destination, the fish must swim through the waters located on the Gilbert Stuart Museum property.

Upon reaching the property, the fish come to a crossroads. Swimming right could be prove fatal, since it leads to a dead end, but swimming left takes them up the fish ladder and safely to Carrs Pond.

To prevent fish from taking a wrong turn, the Nature Conservancy and the Rhode Island Department of Environmental Management have created a “roadblock.”

That roadblock removes the option for fish to swim to the right, and only allows them to swim towards the fish ladder.

The direction that’s been blocked off leads into a “mill run,” which flows between two mills on the property and ends with a dam, according to the Nature Conservancy’s John Torgan.

“These fish were coming up the wrong way, getting stranded and many of them were dying if they weren’t able to be rescued,” he explained.

The mill run is important to the Gilbert Stuart Museum and the property’s history, according to Museum Director Peggy O’Connor.

“The dam that we have here was here at the time Gilbert Stuart lived here,” she explained.

Stuart, according to O’Connor, was a prolific portrait artist in the 18th century, known primarily for his unfinished portrait of George Washington.

“I’m sure you’re familiar with the portrayal of George Washington on the $1 bill,” O’Connor said. “That is from the painting by Gilbert Stuart.”

Torgan said the barrier they installed still allows water to flow through the mill run while also preventing the fish from heading that way.

“Think of it almost like a picket fence. There’s enough space to let some water come through. But not enough space to let the fish through,” Torgan said.

Torgan said the Narrow River is likely one of the most important fish runs for river herring in New England.

“In 2006, looking at the declining numbers [of river herring] across the East Coast, Rhode Island issued a moratorium … no more fishing for river herring,” Torgan explained.

This $54,000-project was funded by the Horace and Ella Kimball Foundation and the Narragansett Improvement and Preservation Foundation. It’s also supported by the Rhode Island Saltwater Anglers.