Ala Wai Canal Flood Control System
Dual Outlet System for the Ala Wai Canal
Technological advances in flood risk management and pollution treatment systems can be utilized to maintain the infrastructure of a dual outlet for the Ala Wai Canal.
Dual Outlet System
How The Ala Wai Canal Puts Honolulu's Most Valuable Real Estate At Risk*
In the 1920s, developers led by businessman Walter Dillingham carved a 1.5-mile channel across the Waikiki landscape, draining the wetlands that had supported taro farming there for generations.
At the time, the goal was to replace those wetlands with a neighborhood that evoked coastal Southern California.
* Honore, M. (2018, October 9). How The Ala Wai Canal Puts Honolulu's Most Valuable Real Estate at Risk. CivilBeat. www.civilbeat.org.
Dillingham Goes To Work **
In 1920, Dillingham's Hawaiian Dredging Co. won the bid to dredge the canal.
Following plans drawn up by the City Planning Commission, Dillingham and his men his quickly got to work, scooping out mounds of sediment with his dredging machine, nicknamed "Kewalo." or in Hawaiian, "place of wailing. But there were problems. The dinosaur-like structure that rose about 50 feet in the air couldn't fit in the 60-foot wide canal that was called for by the engineering plans. The engineers widened the canal to 150 feet. But then the dredging project was still short of enough material to fill in the wetlands. In 1923 the canal was widened again, to 250 feet.
Hawaii State Archives: Ala Wai office, 1934
By mid-1923, the "Kewalo" was making good progress. Lyman Bigelow, the superintendent of public works, announced that the canal had intercepted the Apuakehau Stream "and all the filthy waters which have previously flowed on to this fine swimming beach have been diverted and 'now flow out to the sea by way of the canal. The canal finished in 1927. The western end opened into the ocean at the edge of Waikiki Beach. The eastern outlet, at Kapiolani Park, was never built. Engineers worried that pollution flowing into the ocean would be carried back along Waikiki Beach. Besides, money was running out so the work was wrapped up.
** Cocke, S. (2013, May 20). Ala Wai Canal: Hawaii's Biggest Mistake?
CivilBeat. www.civilbeat.org
Dillingham Goes To Work ***
1917: Plans made to drain wetlands, rice paddies and taro patches in and around Waikiki by digging canal.
1918: Government begins acquiring land, forcing out farmers.
1921: Hawaiian Dredging Co. begins digging.
1928: Digging complete. Waikiki heralded as "Venice of the Pacific."
1929: Warning issued : Canal unsafe for swimming.
1965: Canal overflows, floods Waikiki.
1967: Canal floods Waikiki again. Study looks into opening a second entrance to sea. Canal dredged for first time.
1976: Study'finds Ala Wai regularly violates federal limits on fecal coliform bacteria.
1979: Three teens catch, eat 7-pound Samoan crab. Newspaper runs photo.
1983: City dumps 2.5 million gallons of sewage into canal during Island-wide blackout.
1991: Department of Health posts signs : Do not fish or swim in canal.
2002: Third dredging of canal.
2006: 48 million gallons of sewage dumped in canal; man who goes in dies of massive bacterial infection.
*** Thompson, D. (2017, October 23) Honolulu Magazine.com
"It Came From The AlaWai: 6 Strange Creatures that Thrive in Waikiki's Sewage-filled Canal"
