two additional transcontinental lines were built to the west coast—three in all—but that was far more than the traffic would bear, making the system simply too expensive. one after another, the federal government was forced to take over the lines and cover their deficits. in 1923 the government merged the grand trunk, grand trunk pacific, canadian northern and national transcontinental lines into the new canadian national railways system. since most of the equipment was imported from britain or the u.s., and most of the products carried were from farms, mines or forests, there was little stimulation to domestic manufacturing. on the other hand, the railways were essential to the growth of the wheat regions in the prairies, and to the expansion of coal mining, lumbering, and paper making. improvements to the st. lawrence waterway system continued apace, and many short lines were built to river ports.