BEIJING — China plans to increase its sea water desalination capacity more than fivefold during the next three to five years to ease a water shortage on its inhabited islands.

Around 100 sea water desalination projects will be built or upgraded in 16 coastal provinces and cities, adding 600,000 metric tons of daily desalination capacity to the existing capacity of 135,700 tons, according to a plan issued by the National Development and Reform Commission and the State Oceanic Administration.

By 2020, desalinated sea water is expected to become the main source of water for islands suffering a severe water shortage, according to the plan.

China has more than 11,000 islands in the sea, of which 489 are inhabited with an area of at least 500 square meters. More than half of the inhabited islands depend on pipe systems or cargo boats for water supply.

The news lifted stock prices of relevant companies Wednesday. Beijing Originwater Technology climbed 1.26 percent in the morning to 16.86 yuan (about $2.6). Zhejiang Hailiang Co shares ended the morning session up 0.38 percent to 7.86 yuan.