Ocean Pumping Raises Seafood Output : Aquaculture: Hawaii facility uses deep seawater to produce marketable oysters, lobsters, salmon, giant kelp and vitamin-rich algae.


Pump cold water up from the Pacific depths, and oysters, lobsters and salmon can thrive on a stretch of barren black lava coast in the tropics.

The cold seawater is “nutrient-rich and free of pollutants, perfect for aquaculture,” said Thomas H. Daniel, technical director of the Natural Energy Laboratory here on the West Coast of the island of Hawaii. Scientists at the state-run facility first tapped the water as part of an experiment in ocean thermal-energy conversion, but soon realized that it could do more than generate electric power.

Next to the lab site, the state operates the Hawaii Ocean Science and Technology Park--the only place in the United States where deep seawater is pumped ashore to help produce marketable oysters, lobsters, salmon, abalone, giant kelp and vitamin-rich algae.


The collaboration between lab scientists and innovative entrepreneurs who lease space at the park has worldwide implications for tropical regions where there are sharp differences between the deep and surface temperatures of adjacent waters. The techniques used here offer the tantalizing prospect of harmlessly drawing on the ocean to increase food supplies as well as to produce pollution-free energy.

To tap the Pacific, the laboratory installed 11 pipelines that can bring up 25,000 gallons of seawater a minute, some as cold as 43 degrees Fahrenheit from depths of 2,000 feet. Distribution pipes carry it to fish tanks and ponds.

Strolling among the tentlike structures of the 547-acre park, a visitor encounters long raceways filled with algae and stirred by paddle-wheels that look as if they should be propelling small Mississippi steamboats.

“The paddle-wheels circulate our vitamin-rich algae and make sure it all gets exposed to sunlight, but the key to our production is the cold, clean seawater, which is also full of nutrients,” said Gerald R. Cysewski, president of the Cyanotech Corp.

The 10,000 pounds of algae produced each month are dried to make “spirulina” diet-supplement pills and powders that are used in pharmaceuticals and health foods. The company is also marketing beta carotene, a nutrient extracted from the algae that shows some promise as a cancer preventive.

The tanks, ponds and raceways at Ocean Farms of Hawaii are yielding bounteous harvests of oysters, abalone, salmon and sea urchins. “Most of it is consumed in-state, but we ship some to California, and eventually hope to open markets in Japan,” said Dennis Bishop, the chief operating officer.


The company now has about 500,000 oysters, but plans eventually to harvest more than 2 million a year. “Our oysters are particularly popular because they’re grown in pure seawater. There’s no question of contamination,” Bishop said. “The water’s also perfect for the crop of giant kelp that feeds our stock of 500,000 abalone.”

At Aquaculture Enterprises, both cold and warm seawater is important to its lobster venture. “By increasing or decreasing water temperature, we can speed or slow up the metabolism,” Joseph Wilson, a partner in the company, explained.

In nature it sometimes takes about 7 1/2 years for a lobster to progress from the larval stage to a 1-pound delicacy. “Lobsters hibernate during winter months when the water’s cold,” Wilson said. “Using warm water, we can cut down hibernation time, and bring a lobster to 1 pound in less than three years.”

Business has been so successful that Wilson has to import 1,000 to 2,000 lobsters a week from Maine just to meet the Hawaiian demand. In the next two or three years, his company, which now has 5,000 lobsters, hopes to move into a new facility that will house 1.5 million. “We want to produce at least 500,000 pounds of lobsters a year for Japan and other lucrative Asian markets,” he said.

Some companies at the park are already serving the Japanese market. One grows a sea vegetable used to wrap sushi rolls. Another raises a type of flounder that is often eaten raw by sushi fanciers.

Besides seafood, fresh strawberries grown in the park may someday be on the market. Test beds at the neighboring lab have shown that the fruit flourishes when nourished by the condensation of fresh water that drips from the outside of the pipes that carry the cold seawater.