Farmers Assist in Maunawili Ditch Repairs

On Wednesday, September 19, 2007, the Waimanalo Irrigation System staff of Bill Leleo and Larry Gomez worked jointly with seven Waimanalo farmers and Randy Teruya, Agricultural Asset Manager, to install temporary repairs to the Maunawili Ditch System that collects and transports surface flows in the Maunawili Valley Watershed to the 60 MG Reservoir in Waimanalo.

Since June 29, 2007, the Waimanalo Irrigation System customers had been on a Phase II, mandatory water restriction calling for a 20 percent reduction in water consumption.  The irrigation system’s reservoir storage reached an alarmingly low level of 11 feet on Thursday, September 6, 2007, which prompted the Agricultural Resource Management Division to elevate its conservation measures from Phase II to Phase III, mandatory water restriction, calling for a 30% reduction in water consumption.

The Waimanalo Irrigation System’s three person staff operate and maintain approximately 4 miles of open ditches, pipe siphons, and tunnels that was constructed in 1878 for the Waimanalo Sugar Company.  Additionally, the staff operates and maintains approximately 10.5 miles of distribution pipeline with 90 service connections and the Waimanalo 60 MG Reservoir.

The open, unlined ditches of the more than century old irrigation system has steadily deteriorated and requires major improvements to maintain its efficiency in delivering irrigation water collected for use by the Waimanalo agricultural community. 

Farmers volunteered to work with the Waimanalo Irrigation System staff to install sheet metal material donated by Carl Kobashigawa of Koba’s Nursery.  The sheet metal was formed into a “U-shape” and placed within the open ditch sections that were badly deteriorated and leaking.  The “new” ditch sections will minimize leakage and transport the water more efficiently.

The volunteer farmers were:  Scott Chun, Grant Hamachi, Carl Kobashigawa, Paul Kaneshiro, T.C. Staton, Dominic Kadaoka, and Fred Mencher of Hawaii Marine Enterprises in Kahuku.

	Top and Left:  Waimanalo farmers and HDOA staff use sheet metal to repair a section of the ditch to minimize leakage and improve water delivery (Bottom photos)