Francis also designed the Francis Gate, a flood control mechanism that provides a means of sealing the canal system off from the Merrimack River, and completed the canal system by adding the Northern Canal and Moody Street Feeder, both designed to improve efficiency to the entire system. To further improve the amount of year-round, day and night water power Lowell needed, Francis, along with engineers from Lawrence, were involved with The Lake Company, a corporation involved in building dams in the Lakes Region of Central New Hampshire. These dams, constructed and improved mid-century, allowed the cities on the Merrimack River to store and release water from the Merrimack's source, including Lake Winnipesaukee.