Plans are in place to increase water levels in reservoirs serving Tokyo and surrounding areas in a bid to meet demand during the 2020 Tokyo Olympics and Paralympics.

With more than 10 million people expected to arrive for the games, the central government and seven prefectures including Tokyo will this summer check if increasing water reserves at seven reservoirs in eastern Japan will be enough to avoid water shortages at hotels, restaurants and sports venues without cutting supplies to industries and residents.

Operators of the seven dams on the Tone, Sagami and Arakawa rivers will examine how far they can increase water levels without posing a risk of flooding, officials said.

Tokyo and surrounding areas suffered an "Olympic drought" prior to the 1964 Games as low rainfall led to prolonged water supply restrictions.

The Self-Defense Forces and U.S. troops based in the country provided emergency water supplies ahead of the games to help stem the crisis. The restrictions were eventually lifted just before the games began in October that year.

Although the amount of reservoir water has grown nearly sixfold since then, the country wants to prepare for a worst-case scenario.

According to the Land, Infrastructure, Transport and Tourism Ministry, the amount of usable water in Tokyo can be increased by 20 percent if all measures are taken.

If a water shortage develops regardless of the measures taken, the prefectures may request water stored in reservoirs behind hydroelectric dams operated by Tokyo Electric Power Company Holdings Inc., the officials said.

"We will take all possible measures to ensure a successful Olympics without affecting the everyday lives of residents," an official at the infrastructure ministry said.