Shanghai's larger-than-usual annual water hyacinth outbreak this year was due to the warm autumn season in the country, government authorities said on Wednesday.
The number of water hyacinths growing in Shanghai this year is bigger compared to previous years.
Water hyacinths in the city usually grow in number during the months of October to December, and local officials are used to dealing with the floral outbreak each year. However, the larger scale of this year's bloom proved to be harder for the authorities.
The total weight of hauled water hyacinths from several of Shanghai's waterways since mid-October reached nearly 320,000 tons, which already exceeds the overall haul weight in 2013.
The over-blooming water hyacinths flooded the Huangpu River, the Bund waterfront area, and even the Songjiang, Qingpu and Jinshan residential areas.
According to the Shanghai Greenery and Public Sanitation Bureau, the water plant was already spotted since mid-July in some of the city's river courses. The growth of the water hyacinths this year was earlier than usual, it said.
The bureau also said that the warm weather this year, which increased further this fall, intensified the growth rate of the water plants.
Removal of the invasive water species in the city's waterways will most likely continue until January next year, the bureau said.
However, the larger growth in the number of water hyacinths in the city is not all bad news as some of Shanghai's districts convert the hauled water plants into fertilizers. Some of these districts include Fengxian, Songjuang and Qingpu.