A cleanup of Beijing's oldest canal will be completed this year, according to the city's Development and Reform Commission.

Stretching 23 kilometers, the Xiaotaihou Canal runs from downtown Chaoyang district to the southwestern suburb of Tongzhou.

The man-made waterway, around since 988, was full of aquatic life before the 1950s. However, it gradually became polluted after being used as a main drainage outlet.

Restoration work started in November, and a wetland area totaling 710,000 square meters is now being built along the canal in Chaoyang to restore its ecological function, according to Zhang Huanshan, chief engineer of the district water authority.

The canal is currently dry but is expected to fill with rainwater once the rainy season starts in June, he added.

Wang Liping, landscape design manager at Beijing Enterprises Water Group, said cleanup efforts in Tongzhou have focused on preserving cultural relics, with the redevelopment plan changed three times to protect an ancient bridge.