Hanoi's Cự Khối Reservoir Halfway Complete, Aims to Reduce Eastern Flooding

After nearly a year of construction, the Cự Khối reservoir in Long Biên district, Hanoi, is about 50% finished. The project covers roughly 30 ha of water surface within a 38.3 ha site and has attracted an investment of almost VND 1 trillion (about USD 40 million). Alongside the lake, a 2.6‑km drainage canal (Vietnam‑Hung‑Cầu Bây) 19–30 m wide is being built to link the reservoir with existing pumps and sewer lines.

The partially excavated basin can already hold water to help mitigate flooding during heavy rains. Completion of the lake basin and surrounding canals is expected by the end of 2026, with full operational use targeted for early 2027. When operational, the reservoir will improve water drainage for eastern Hanoi, reduce flood risk, and provide added urban green and recreational space.