Seattle and Tacoma are being stymied in their push to regain market share from Canada as railcars destined for the harbors sit idle on tracks across the U.S. Pacific Northwest. Even as the ports, on Washington’s Puget Sound, agreed to consolidate some operations after a century of competition, 40-fold growth in shipments of crude from the Bakken oil fields is straining the region’s main railroad company, BNSF Railway Co., causing delays that have helped shift traffic to less congested harbors in Canada. In September, as many as 150 grain cars piled up in nearby rail yards, said Dale Frazier, manager of Seattle Bulk Shipping Inc. “We were turning away business,” Frazier said by phone on Oct. 28. His company transfers grains, peas and lentils from hopper railcars into containers for export. His customers racked up $170,000 in extra storage bills in September, up from $30,000 in July, he said. […]