Demand outpacing water supply on Okinawa
NAHA, Okinawa — Recent rains have done little to reverse the receding levels of Okinawa’s reservoirs, but water rationing has been set aside — for now.
Members of the Okinawa Drought Countermeasure Council met Friday to discuss the island’s decreasing reserve supply of water, noting that the level at nine reservoirs on the island was 59.6 percent of capacity, a drop of 4.2 percent in the past two weeks.
The focus of the meeting was how to stretch water resources while waiting for the island’s rainy season, which traditionally begins in May.
Rationing was considered but will not be implemented in the near future, said Masaaki Mantoku, senior engineering officer for the Okinawa General Bureau, an agency that manages the island’s six national reservoirs.
“However, if the situation does not improve, rationing could be unavoidable,” he said.
Mantoku said the problem is a combination of the second lowest annual rainfall in the past decade and the second largest water demand ever recorded on the island. Some 1.3 million people live on Okinawa, including about 50,000 Americans.
“Total precipitation in northern part of the island, where five of the nine reservoirs are concentrated, was 71 percent of the yearly average,” he said. Meanwhile, the average daily demand rose to 461,800 tons.
And weather forecasters predict little January rainfall. As of Thursday, the total rainfall in northern Okinawa was 2.24 inches, about 38 percent of the monthly average, according to the Okinawa Meteorological Observatory.
“In February and March, we expect average rainfall,” a spokesman for the observatory said Friday. “But that would be far too small to make up for the present shortage.”
Mantoku said tourism is responsible for both the increased demand for water and the reluctance of prefectural officials to call for rationing.
A record number of tourists visited Okinawa last year, boosting demand for fresh water, he said. But rationing measures would hurt the island’s tourism industry.
“If rationing measures were taken, rumors would spread throughout Japan, discouraging people from visiting,” he said. “Such rumors are very harmful to Okinawa’s tourism.
“To avoid such situation, and to secure an adequate water supply, we agreed to make every effort by utilizing every possible alternate way to conserve water,” he said.
A new water desalinization plant in Chatan is running at capacity, producing 40,000 tons of water daily, he said. He also said about 21,000 tons of water, normally set aside daily for industrial use, could be converted to public consumption.
“But, the amount is very small compared to the total daily demand of 450,000 tons,” he said. “It is like a drop in the ocean.”
The last time Okinawa had water rationing was for 31 days in early 1994. At that time the island’s water supply was turned off for eight hours a day.
Mantoku said that the council members would meet again if the situation further worsens.
“When we meet the next time, rationing would be strongly considered,” he said. “Because, if nothing is done, we will reach a level of crisis April or May.”