The National Environment Management Authority has shut down 36 factories for discharging industrial waste into water bodies.
Nema director general Geoffrey Wahungu told the Star exclusively on Saturday that the purge is also targeting six government institutions.
"We will continue to close and open those that have fully complied with laws on effluent discharge," Wahungu said and disclosed that they were also focusing on air pollution
He said three factories have re-opened after complying with environmental laws.
"One of them actually installed an effluent treatment plant within seven days. The other two took two weeks."
Wahungu explained, "We have two forms of closure. Where a factory is doing both wet and dry processes, we are closing the wet process. If the whole factory is dependent on wet process, we entirely shut down the whole factory. Most of the factories are located along the Nairobi River"
Government Institutions are however given a grace period to shape up.
"We have a big problem particularly with colleges, universities, hospitals and a few middle-level institutions," he said.
Sugar factories, timber manufacturing and cement factories are also polluters.
Wahungu spoke to the Star during tree planting at Ruiru presided over by First Lady Margaret Kenyatta. More than 10,000 bamboo tree seedlings were planted around Ruiru dam. The dam is one of the main sources of water for Nairobi residents.
The Nema boss flagged the Technical University of Mombasa as one of the institutions given the grace period due to the problem of getting students out.
"The university will close in August after being given one month to repair sewerage system," he said.
To curb air pollution in Nairobi, Wahungu disclosed that they will be testing and reporting ambient air quality (concentration of pollutants in the air) in the next one month.
Nema is working with the Kenya Meteorological Department to test the air quality.
The funding will be from the National Treasury.
Wahungu called on the citizens to be vigilant against air pollution. They are already working on stationary emissions mainly from factories.
"For mobile sources, I hope in the next six months we can do it."
The agency recently acquired a mobile air quality monitoring laboratory.
The Nema boss said one of their main challenges is that air pollution is partly a devolved function.
"Most of the industries were relocated in the 1970s and 1980s and the spaces they left have been encroached on by human settlement, gated communities and estates which are now starting to agitate against poor air quality."
The Institute for Health Metrics and Evaluation says that 17,000 to 20,000 Kenyans die annually of air pollution and related causes.
Wahungu said the factories were being engaged to help them comply. "They need to put more expensive and effective equipment to be able to meet the standards for being in an industrial area where people are also settled."
This year's World Environment Day focused on air pollution.
"We have built a lot of capacity and raised awareness to communities and also to county governments," Wahungu said, noting that zoning is key if air pollution is to be addressed effectively.
He said they had been optimistic of cleaner air after the government decided to limit the age of imported vehicles from eight down to five.
"That has not worked very well, I do not want to say we are going back to the drawing board but what we want is to have at least a year of sensitisation and grace period for motorists to prepare," he said.
The Nema DG said personal vehicles will be tested every two years.
Billboards will be mounted in the streets to raise awareness of clean air.
