Cheney and her father, former GOP vice president Dick Cheney, endorsed Harris last month over GOP nominee Donald Trump.
Only a fraction of the Great Lakes' bottom has been mapped, and those low-resolution charts were completed decades ago.
Some manufacturers and retailers are urging President Biden to invoke the Taft-Hartley Act as a way to suspend a strike by 45,000 dockworkers that has shut down 36 U.S. ports.