Hawaii’s dependence on agriculture has largely diminished over the past 30 years—a change that has negatively impacted the water table in areas such as the eastern portion of Kaua’i. The flood-type irrigation traditionally used for sugar cane farming had continually replenished the underground aquifers, which are the primary source of drinking water for the island. As the population continues to grow, and water demands increase, an alternate source of water is needed to provide adequate supplies of drinking water.
Rainfall run-off provides an abundance of surface water on Kaua’i. In fact, Mount Waialeale is recognized as one of the wettest spots in the world, with an annual average rainfall of 460 inches (1,168 cm). By combining GE’s ecomagination-certified ZeeWeed membrane ultrafiltration technology and a century-old reservoir and irrigation system, Grove Farm Company is collecting, storing, and treating rainwater to supply as many as 15,000 residents and visitors with a new source of drinking water.
Grove Farm, a land management and community development company, uses its historic irrigation ditches to direct a significant portion of rainfall into its 75 acre (30.4 hectare) Kapaia Reservoir. GE’s ZeeWeed ultrafiltration system at the compact, unobtrusive Grove Farm Water Purification Plant (WPP) draws water from the reservoir and produces up to three million gallons (11,356 m3) of drinking water per day for the surrounding communities.
In September 2008, GE recognized Grove Farm’s innovative and environmentally responsible solution for water resources, with a GE ecomagination Leadership Award. Ecomagination is GE’s corporate-wide initiative to address challenges such as the need for cleaner, more efficient sources of energy, reduced emissions and abundant sources of clean water. The GE ecomagination Leadership Award is given to the top one percent of GE Water’s customers who demonstrate significant environmental and economical performance improvements.
Designed and built by Aqua Engineers of Kaua’i, the water treatment plant incorporates four ZeeWeed membrane trains, each with an average design capacity of 0.75 MGD (2,839 m3/d) and a maximum capacity of 1 MGD (3,785 m3/d). ZeeWeed membranes act as a physical barrier to virtually all suspended particles, and can consistently provide > 4-log removal of Giardia cysts and Cryptosporidium oocysts and > 2 log-removal of viruses.
Each train can be expanded for a maximum capacity of 1.12 MGD (4,240 m3/d) by simply adding additional membrane cassettes. The use of multiple process trains enables the plant to operate for extended periods with one train off-line for cleaning or maintenance by increasing the flow through the remaining operational trains. The design also includes pretreatment by enhanced coagulation.
Grove Farm has played an integral role in Kaua’i history for nearly 150 years," said Warren H. Haruki, president and CEO of Grove Farm. "We recognized the challenges facing Kaua‘i and have implemented a sustainable solution to alleviate our island’s dependence on traditional water sources. With the assistance of innovative companies such as General Electric, and the pioneering partnership with our local Department of Water, we are extremely proud of our Water Purification Plant and we will continue to explore new ways to benefit Kaua‘i. Our broader goal is to implement sustainable technologies for renewable energy and food production.
Grove Farm Company completed construction and opened the water purification plant in September, 2005. Treated water from the plant is sent to the County of Kaua‘i Department of Water, which has contracted a 15-year, public-private partnership with Grove Farm to purchase and distribute two million gallons (7,570 m3) of water per day to the surrounding homes and businesses.
Along with the construction of the water purification plant, Grove Farm also created new habitat areas for Hawaii’s state bird, the Nene Goose, on lands adjacent to the water plant. Three habitat areas, totaling eight acres (3.2 hectares), were enhanced to benefit the Nene, which is recovering from the brink of extinction. The company has coordinated two successful releases of the birds and the Kapaia Reservoir is currently home to approximately 25 Nene.
