Dong Hui/ Shanghai Daily news

A noxious infestation of water hyacinth has been discovered in the upper reaches of the Huangpu River, Shanghai Public Sanitation Bureau said on Friday, Shanghai Daily reported.

The water hyacinth has formed a 10-kilometer belt on the river, 10 to 40 meters wide, near the gateway of the river.

Officials from the bureau said the infestation may affect the waters but they will try their best to minimize the threat.

This year's water hyacinth seeds are smaller than before and easier to pass through traps and collection sieves. The water hyacinth infestation flowed into the Huangpu River and Suzhou Creek from 158 tributaries.