Industrial pollution, human waste blamed for the Water hyacinth choking R. Chania.

A Section of River Chania that is heavily infested by the green like vegetation.

Experts are pointing an accusing finger to industrial pollution discharged from factories and waste water released by residents into River Chania as the two main reasons for the fast growth of the water hyacinth that is now threatening to choke the town's largest river.

River Chania is now on the verge of extinction following increased invasion by the notorious water weed on parts bordering some of the manufacturing industries in the area, especially the area below St. Xavier Girls’ High School near UTI Estate.

The river has been heavily polluted by the industries effluents and raw human waste water freely flowing into it illegally.

“The plant thrives on fresh water bodies that have been polluted by chemical effluents containing nitrate fertilizers which explains why the weed spreads so rapidly along parts of the river bordering some of these manufacturing industries,” explained Mr. Donatus Njoroge, a researcher at the Mt. Kenya University (MKU).

Some residents working nearby however believe the plant may have been accidentally or voluntary thrown into the river upstream before it was swept downstream by unsuspecting persons or by people who knew what they were up to since it is rare in the area.

“The plant must have been brought to the river by someone accidentally or voluntarily and thrived well on the parts that have huge nitrates deposits,” said James Mumu Thika resident.

However, Njoroge refuted this saying that as much as it could be true, it was not definite. He added that the plant may have as well been washed downstream into the area from other parts of the country where the plant thrives before spreading along Thika area due to the high rate of nutrients deposits into the river without having been brought there by a particular person.

“The impact of this on the residents is increased cases of malaria and waterborne diseases like bilharzia. The weed is a good breeding ground for mosquitoes and other insects. It also interferes with irrigation activities and water treatment works," said Mr. Njoroge.

Water hyacinth has been branded as the world’s worst aquatic weed due to its invasive potential, negative impact on aquatic ecosystems, and the cost it necessitates to control it. Removing this weed is usually very difficult because once it is established in a water body, it spreads through wind propulsion of floating plants (or plant fragments), through water currents and on the feathers and feet of the numerous species of local and migratory water birds.