More than 50 years ago, Robert Moses designed a freeway that sliced through the South Bronx, cutting many residents off from the riverfront. On Sunday, Gov. Andrew M. Cuomo of New York endorsed a plan to tear down that road, the Sheridan Expressway, and replace it with a tree-lined boulevard that could stitch the community back together.

Mr. Cuomo said he intended to include nearly $700 million in the state budget for the first phase of the project, which would involve the rare step of decommissioning the expressway, also known as Interstate 895. That would be the first significant funding of a plan that community activists and some local elected officials have championed for more than 15 years.

“This is transformative,” said Ruben Diaz Jr., the Bronx borough president. “You cannot put any dollar figure on the amount of quality time that families are going to be able to spend along the river.”