After a flood destroyed a mill constructed by his father, Jefferson had his enslaved workforce begin an ambitious plan of rebuilding both the mill and constructing a canal. Completed in 1803 after almost thirty years of intermittent work and a cost of about $20,000, the canal ran alongside the Rivanna for about three quarters of a mile. At the end of the course, Jefferson had two flourmills built. One of the flourmills was for Jefferson's own use. The second, built at a cost of $10,000, was leased out for commercial use.
Jefferson's Mills

Short video on Jefferson's Mills at Monticello

Research Archaeologist Derek Wheeler discusses Thomas Jefferson's milling ventures along the Rivanna River.
Related articles
Thomas Jefferson's Daily Ride

A retracing of Jefferson's daily ride around his 5,000-acre Monticello plantation.