中国的雨水循环再利用

As one of the fastest growing cities in China with a population of over 23 million, Shanghai is facing with a water shortage. Only one percent of its surface water meets the state standard for drinking because of pollution.

Some have found an alternative water resource in rainwater.

At a farm with the rainwater reuse systems, the V-shaped roofs of the greenhouses gather as much water as possible on rainy days. The water will then be transferred to two reservoirs.

After being processed, it will reach the vegetables in the fields.

Zhang Ting is a greenhouse manager at the Sunqiao Modern Agriculture Development Zone in Shanghai.

"These two reservoirs provide rainwater for 30,000 square meters of greenhouse plants all year long. We haven't used a single drop of tap water since the first day."

The Pudong international airport has the largest landscape pond in China, but it needs 265,000 tons of water every year. Reusing rainwater has helped the airport to save 4.5 percent of annual water usage since 2011.

Gao Yun is the deputy general manager of Energy Security Department of Shanghai Int'l Airport Company.

"We use the processed rainwater from the airport's surrounding river for the pond and gardening. We will extend it to the toilet flushing system in terminal 2 by the end of this year. It's part of our green airport strategy."

With almost 45 million travelers passing through last year, this snack change will save about 1,500 tons of tap water every day. An Australian tourist says collecting rainwater is common in his country.

"I think it is a good thing if you can use water that has already been used. In Australia, we often use tank water to flush toilets, so that we don't use drinking water."

The rainwater reuse system has now been more widely implemented in not only Shanghai, but also many other cities in China.

Cities of Zhengzhou and Jiyuan in central China's Henan Province have implemented rainwater reuse systems as well.

In Zhengzhou No. 1 High School, a round catchment with holes was used for collecting rainwater. After processing, the water will be used for irrigation of the campus, which may save 50,000 tons of water and cut expenses by about 120,000 yuan.

With years of promotion, the rainwater reuse system has brought benefit to Henan Province.

According to statistics from 2012, the water usage for each 10,000 yuan of GDP growth decreased from 150 tons in 2006 to 64 tons in 2011, and the reuse rate of the water was elevated from 62 percent to 72 percent. As for agriculture irrigation, the water usage decreased from 198 tons in 2006 to 164 tons in 2011.

For CRI, I am Li Dong.