Country-Director Mohammed Awer hands over water monitoring equipment to Engineer David Mumo. [Antony Gitonga, Standard]

Milk and vegetable processing plants in Nyandarua County have been identified as the biggest polluters of rivers within the Lake Naivasha Basin.

Trading centres and livestock have also contributed, in a big way, to the befouling of the rivers, an initial survey carried out by the Water Resources Users Associations (WRUAs) has indicated.

The report follows an exercise by nine of the 12 WRUAs in the basin which are carrying out a water health assessment to identify pollutants of local rivers.

Mr Enock Kiminta, the chairman of Lake Naivasha Water Resource Users Association (LANAWRUA), said their objective is to establish the quality and quantity of the water in the rivers within the basin.

Fishermen on an expedition at Lake Naivasha. [Antony Gitonga, Standard]

"We shall look at the current status of the rivers flowing from the Aberdares into Lake Naivasha," said Kiminta who spoke on Thursday in Kinangop.

He added: "Our initial investigations have indicated that there is pollution from some food processing plants. Some milk and vegetable processing plants have been identified as the main polluters of rivers. We are working with these companies to resolve the problem.”

He said they have advised the companies to construct artificial wetlands to deal with their waste as one way of addressing the problem of pollution.

"Local communities, factories, and WWF-Kenya, have backed the exercise. Data that will be collected will go a long way in assessing the current state of the rivers, emerging challenges, and mitigation measures,” Kiminta said.

The information collected would be shared with government agencies for appropriate actions to make the water from the rivers cleaner.

"Those around the rivers have been advised not to farm on the riparian land. And we have trained them on how to test the quality of the water,” Kiminta said.

Pat clean up exercise at Lake Naivasha. [File, Standard]

Mr Samuel Mwangi, one of the farmers, said the quality and quantity of water has improved tremendously since they stopped farming on the riparian land.

“We have been taught how to use the water testing kits and gathering data as part of making sure water from our rivers is fit for human consumption,” he said.

Dr William Ojwang, from WWF, said the water testing kit would assist in collecting data on the quality and quantity of water within the basin.

“As demand for water rises, we have decided to engage the farmers so that we can know the amount of water and its quality,” he said.