The building of the Union Canal to connect Philadelphia with the Susquehanna, the Chesapeake and Ohio Canal project, and other plans of eastern cities for securing the trade of the western territory caused growing concern in Baltimore. In 1823 a survey was made for a canal from the Conewago Falls along the western bank of the Susquehanna to a point near Havre de Grace, thence across the low- lands to Baltimore. This project was not carried out at the time, but in 1835 the legislatures of Pennsylvania and of Maryland au- thorized canals, respectively, from Wrightsville to the State Line and from the State Line to Havre de Grace, subsequently united as the Susquehanna and Tidewater Canal. Excavation started in 1836, and the canal was completed in 1840. Owing to high prices in the boom period of the 1830's, the total cost was $3,500,000, the third greatest for an ante-bellum waterway. The canal was 45 miles long, with a width of 50 ft., a depth of 5 to 6 ft., and locks 170 ft. long and 17 ft. wide, permitting it in later years to accommodate boats of 150 tons capacity. The enormous capitalization and indebtedness prevented its being profitable, but it enjoyed a large volume of business over a period of years. A large part of the traffic went to Baltimore, but for fully 20 years, from 1840 to 1860, more than one- fourth of it consisted of trade with Philadelphia that passed through the Chesapeake and Delaware Canal, owing to the fact that the Union Canal was too small. After the 1860's railroad transportation caused a rapid decline in the traffic on the Susquehanna and Tide- water Canal, and in 1 870 the canal company leased the property for 999 years to the Philadelphia & Reading Railroad Co. Inadequate maintenance resulted in a still further decline in business. In 1894 a freshet greatly damaged the banks of the canal, which were never repaired, and in 1895 the lock gates were permanently closed.