A surprising decision yesterday by the state water commission drew derision from environmentalists and some native Hawaiians as a "miscarriage of justice" and rule by "plantation politics" rather than law.

At issue was the diversion of water by Hawaiian Commercial & Sugar Co., the island’s last sugar plantation.

Chris Benjamin, company general manager, said the decision preserves enough access to water, although it will increase pumping costs in some areas.

"The decision itself doesn’t shut us down," he said.

County water officials also said they can live with the decision.

"Overall, from what I can gather, the decision remains favorable to the County of Maui," said Jeffrey Eng, county water director.

The state Commission on Water Resource Management approved yesterday the return of 12.5 million gallons of diverted water daily from the West Maui Mountains to streams in Waihee, Iao, Waiehu and Waikapu.

But that was far below the 34.5 gallons outlined in its initial plan last year.

"We are very disappointed by this shortsighted political decision that caters to corporate interests while denying good environmental stewardship and the rights of native Hawaiians," said Irene Bowie, executive director of Maui Tomorrow.

John Duey, president of Hui o na Wai Eha, said his members were shocked at the commission’s rewriting the prior recommendation but believes the decision will not stand in the courts.

Just two weeks ago the commission decided to return some diverted water to six of 19 East Maui streams, but not enough to quiet environmental critics, nor the uneasiness of the county about adequate water supply in Upcountry areas during droughts.

Water commission Chairwoman Laura Thielen said the county will need to turn to alternative sources of water, including reclamation and conservation. She said there is simply not enough water in the streams to meet all demands.

Hawaiian Commercial & Sugar Co., employing 800 people in sugar production and related work, has said the lack of access to enough water could close the business.