However, it wasn't until 1864 that the process for constructing a lighthouse was set in motion. The committee of the lighthouse board officially determined that the southern end of the bay needed a lighthouse. Dredging began in the fall of 1866 and a channel—200 ft. wide, 9 ft. deep, and about 2 miles long—was cut right through Grassy Island. Sheet pilings were installed along the banks of the channel to prevent the sand from falling back in.
Finally, in 1872, two lighthouses were built on the east side of the channel. Both were painted white but in 1934 were painted green in order to help sailors distinguish them from Green Bay's lights. They were place 700 feet apart and several other structures, including the keeper's house, a woodshed, and a boathouse were also built. One lighthouse was designed to be 35 ft. tall and the other 25 ft. tall in order to help sailors determine the direction, either north or south, they were headed. The shorter lighthouse was closest to the mouth of the river.
The lighthouses had several keepers. Louis Hutzler served as keeper for thirty-three years from 1903-1933, the longest term held by any keeper. Gas lights were installed in 1934 and as result keepers were no longer needed. The lighthouses continued to assist sailors navigate the entry into the Fox River until 1966, when the need for more dredging became apparent. It was suggested that the lighthouses be burned but members of the Green Bay Yacht Club mobilized an effort to save them and they were moved to the club's parking lot that same year. They remained there until 1999 when they were moved to the breakwall along the east bank of the river that protects the docks. After a restoration effort that lasted several years at the cost of around $400,000, the lighthouses were dedicated in a public ceremony in November 2005.