Northwest China's Shaanxi Province will build ten sewage disposal plants to reduce pollution in the Weihe River, the largest tributary of the Yellow River, China's second longest river.

The Weihe River, the largest tributary of the Yellow River, is heavily polluted.

The construction of the sewage plants started yesterday as part of the provincial government's effort to improve the water quality of the river.

By 2010, a total of 40 sewage plants will be built to curb water pollution along the whole Weihe River.

Provincial statistics show that more than 800 million tons of sewage and wastewater is discharged into rivers in the Weihe basin annually, about 18 percent of the total in the Yellow River basin.

The 800-kilometer-long Weihe River originates in Weiyuan County of northwest China's Gansu Province, crosses the western part of Shaanxi and empties into the Yellow River.

(Xinhua News Agency October 22, 2007)