CTG's Baihetan project aims to keep sewage from flowing into Jinsha River

Walk into the living campsite of Baihetan hydropower station. You'll see the old trees flourishing on the roadside, roads being sprinkled with water, flowers and plants being watered......The garden workers set to work early. This is the green side of the world's largest hydropower plant under construction. A 24-hour domestic sewage treatment station is in operation in the living campsite.

The station utilizes advanced technology to purify domestic sewage, which has a high organic content. The results of the online water quality monitoring system show that the sewage treatment rate is 100%, and the water qualitymeets China's A-level discharge standards in various metrics.

In the living campsite, where tens of thousands of builders reside, there are five such sewage treatment plants, with a total design capacity of 7,000 cubic meters per day.

"In fact, we have also carried out upgrading and reconstruction.In addition to meeting the A-level sewage discharge standards, we have also built a supporting system for water reuse. Thanks to that, domestic sewage can be reused for greening and irrigation after treatment," said Chen Yang from the technical department of CTG's Baihetan engineering construction unit. "The total reuse of sewage reached 413,100 cubic meters in the first quarter of 2021."

Meanwhile, the concrete mixer washing and wastewater treatment and recycling system is able to separate the wastewater from sand and gravel. The separated coarse particles are transported to the spoil area. The separated water is reused for washing concrete mixer after efficient and deep purification. The separated sludge is separated into mud and water again.The resulting mud cake will be shipped to the spoil area, while the clean water is diverted to clean water reservoirs for reuse.

This system, at its peak, treats wastewater from 15,000 concrete mixers per year on average, eliminating sewage discharge. At the same time, other sand, gravel and aggregate processing systems and concrete production systems also come with a centralized wastewater treatment system.All the treated wastewater is reused for system production. "The amount of water saved in a year is equivalent to 1.5 times the capacity of West Lake (a renowned freshwater lake in Hangzhou, Zhejiang province whose surface area measures 6.4 km²), " Chen Yang said.