The Whitewater Canal and the Cincinnati and Whitewater Canal joined in Harrison to provide better access to Cincinnati markets and the Ohio River. The Indiana Internal Improvement Act of 1836 authorized the Whitewater Canal, which was completed from Brookville to Lawrenceburg in 1839. Nearby Dam No. 1 on the Whitewater River created a pool for canal boats to cross the river. The Cincinnati and Whitewater Canal was incorporated by the Ohio General Assembly in 1837 and was completed for seven miles from Harrison, now West Harrison, Indiana, to Dry Fork Creek, Ohio, in 1840. The twenty-five mile canal opened in 1843 when the 1,782 foot tunnel at Cleves, Ohio, was completed. Traffic diverted to Cincinnati on this interstate transportation link diminished Lawrenceburg's importance as a market.