Welland Canal Port Maitland. With the opening of the extension, the canal stretched between the two lakes, with 40 wooden locks. The minimum lock size was , with a minimum canal depth of . Deterioration of the wood used in the 40 locks and the increasing size of ships led to demand for the Second Welland Canal, which used cut stone locks, within just a few years. In 1839 the government of Upper Canada approved the purchase of shares in the private canal company in response to the company's continuing financial problems in the face of the continental financial panic of 1837.
First Welland Canal 1818, when the flow was especially low, Merritt pursued the idea of bringing water to his mills from the Welland River. On a bigger scale, the Erie Canal, dug from the Hudson River through northern New York, was about to reach Lake Erie. The impending completion meant the cargo from upper Great Lakes was about to head down the canal and Hudson River to New York City, bypassing its previous destination, Montreal. At the time, a considerable rivalry existed between Montreal and New York for cargo headed to Europe via ocean-going vessels. All of these factors contributed to the construction