The West Lake Management Board (the investor) announced on 5/8 that it is preparing to open bids for the West Lake water replenishment project. The project involves transforming the approximately 6-hectare Sen Lake into a filtration area with aquatic plants and a wetland park. It also includes constructing a bio-dike combined with a management road and park walkway, installing decorative lighting, and building pipelines to draw water from the filtration area to West Lake.
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Sen Lake serves as a pre-settling area to improve water quality before it enters West Lake. Photo: Vo Hai |
Sen Lake serves as a pre-settling area to improve water quality before it enters West Lake. Photo: Vo Hai
The water source for West Lake will be treated water from the West Lake wastewater treatment plant, with a flow rate of about 13,000 m3/day (design capacity of 15,000-22,800 m3/day). The treated water meets the standards outlined in the discharge permit issued by the Ministry of Agriculture and Rural Development. This treated water currently flows into the Nhue River through the B Xuan La outlet.
According to the West Lake Management Board, after the bidding process, a nearly 2-hectare pilot filtration area with aquatic plants will be constructed and tested before 30/8, and water replenishment to West Lake will begin before 2/9.
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Treated water from the West Lake wastewater treatment plant will be supplied to West Lake. Photo: Vo Hai |
Treated water from the West Lake wastewater treatment plant will be supplied to West Lake. Photo: Vo Hai
In February, the city assigned the Department of Construction to research and propose a plan to draw water from West Lake to replenish the To Lich River through the West Lake A regulator - Do culvert - Thuy Khue canal if needed to maintain the river’s water level. This project is to be completed in August.
To ensure stable water levels in West Lake and prevent any adverse effects from supplementing the To Lich River, Tay Ho district is tasked with proposing a plan to use water from the Red River and treated water from the West Lake wastewater treatment plant to replenish the lake.
In the long term, the city has requested the Department of Construction to review relevant planning, conduct thorough research, and propose a plan to replenish the To Lich River with water from the Red River along Vo Chi Cong Road (connecting with the implemented short-term water replenishment plan). This plan should ensure both the To Lich River's water supply and stable water levels in West Lake.
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Illustration of the solution to bring treated water from the wastewater treatment plant to Sen Lake and supplement West Lake. Source: West Lake Management Board |
Illustration of the solution to bring treated water from the wastewater treatment plant to Sen Lake and supplement West Lake. Source: West Lake Management Board
West Lake is the largest natural freshwater lake in northwest Hanoi, covering nearly 530 hectares with a circumference of about 19 km and a water volume of approximately 10 million m3. Research by Tay Ho district reveals a diverse aquatic ecosystem in West Lake, including 72 species of floating plants, 47 species of benthic algae, 37 species of zooplankton, 29 species of benthos (such as shrimp, crabs, mussels, snails, and worms), 12 species of crustaceans, and 46 species of fish.
Over the years, the water quality of West Lake has shown signs of decline, with some environmental indicators exceeding permissible limits, especially during the dry season, highlighting the significant need for water replenishment during this period.
Vo Hai
