History of the Jetties - by Capt. Bond of the COE. Major W.W. Harfs made an examination of Humboldt Bay in 1877. He reported that masters of steam vessels up here have seen waves breaking 8 - 10 fathoms of depth. Improvements such as jetties was undertaken with misgivings. Originally the bay was defined as having a well defined channel 9 - 25 feet in depth and constantly shifting over a mile and a half. The first project calling for a single jetty on the south side was adopted in 1884, modified in 1888 and again in 1891. Construction began in May of 1889 and completed in August of 1899 at a cost of $2,000,000. They didn't last long. The present project, adopted in 1910, provides for rebuilding the jetties. A gantry crane runs on rails set in the 22' feet wide concrete cap. It's costing about $1000/L.F. for this seasons work. The shallowest water is out beyond the ends of the jetties.