For the purpose of sampling of deep sea water (DSW), a movable type pumping device easily installed on board such as tug boat, was developed, and pumped up DSW at 35 km Miyako, Iwate in Sanriku. The device and the characteristics of DSW obtained were described. Considering the temperature, DSW should be pumped at least from the depth of 550 m or below off Sanriku.

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In order to investigate the seasonal variations of the nutrients of the deep seawater (DSW) from Sagami Bay, we collected water samples from the depths of 0, 100, 200, 300 and 400m, from July 1999 to January 2000, off Odawara.
Temperature, salinity, concentrations of total inorganic nitrogen (TIN), phosphate (PO₄-P) and silicate (SiO₄-Si) at 400 m depth were 8.9±1.4°C, 34.36°C0.06psu, 25.1±4.8μM, 1.8±0.3, μM, 50.1±11.2μM on average, respectively. N: P ratios were approximately 14 under 200 m depth. Concentrations of TIN, PO₄-P and SiO₄-Si were high in July and August 1999 and January 2000, when the North Pacific intermediate water prevailed. From October to December 1999, possible effects by the Kuroshio current became strong, and the concentrations of all nutrients determined were low compared those determined in the former period.
These results indicate that concentrations of nutrients of deep seawater could fluctuate in relatively large extent due to possible temporal variations of the Kuroshio current and the North Pacific intermediate water in Sagami Bay.
As temperature, salinity and concentrations of nutrients of DSW in Sagami Bay were comparable to those at the Cape Murotomisaki and Suruga Bay, which is low temperature, high nutrients and temporally stable of those characteristics, the DSW of Sagemi Bay seems to have suitable characteristics for applying business uses of DSW.

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Deep ocean water has long been known for its stable characteristics of rich mineral ingredients, a low water temperature, and chemical and bacteriological purity, but the effects of deep ocean water on skin physiology remain obscure. In this study, we examined how cultured human skin keratinocytes responded to exposure to deep ocean water from the coastal waters of Toyama Prefecture. We found that these waters promoted not only keratinocyte proliferation, but also the formation of cornified envelope in the process of keratinocyte maturation (differentiation) into cornified cells. After reviewing the mineral ingredients in the seawater, we concluded that silicate promoted this envelope formation, and that coexisting calcium accelerated the effect of the silicate. As the homeostasis of skin depends heavily on a balanced skin turnover, with finely tuned coordination between proliferation and differentiation, this deep ocean water from Toyama is expected to be useful for skin care.

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Deep ocean water (DOW) has attracted special interest as one of the renewable resources with great potential. The purpose of this study is to evaluate feasibility of a large scale DOW pumping-up/distribution, on the assumption that the demand of the DOW significantly increases in the near future. In this paper, economics for two types of the DOW pumping-up systems, floating-type and land-based systems, are investigated as the first step of this study. The results of the economic analysis show that the break-even point price of DOW for floating-type is lower than that for land-based one, and the price of the desalinated drinking water becomes comparable to present public service water when the capital share rate is higher than 50%.

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In order to make practical use of the deep sea-water (DSW) on commercial base, it is desired to have a large quantity of DSW for many purposes, especially for using its energy resource. For example, in case of using DSW for cooling a power plant of 600mega-wat, the required volume of DSW is estimated as large as 1, 000, 000 m³ per day. When such large quantity of DSW is discharged to the coastal sea area, it is necessary to study how to discharge DSW with a minimum damage to the ecosystem or even with giving positive influence (s).
The swirl flow discharge head was then proposed for discharging such a large quantity of DSW, and its basic character was evaluated by the experiments in the present study.

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