Nairobi — The world-renowned Lake Nakuru is threatened with extinction in the next few decades. The alkaline water body has gradually shrunk over a 30-year period from 48 sq km in the 70s to less than 37 sq km today and could be extinct with 50 years. "Siltation is today the biggest threat to this lake," says Joseph Warutere, a Kenya Wildlife Service (KWS) senior warden at the Lake Nakuru National Park.

"Most of the foreign debris and silt finds its way into the lake through rivers that flow into the lake from the surrounding hills," he adds.

The debris is gradually taking its toll on the lake as it hampers the growth and development of the blue green algae, which the lesser flamingoes feed on.

"The blue-green algae, like any other plants, need light for growth," explains he. "However, when the debris settles on top of the water, light is unable to penetrate to aid growth."

Following massive excision of the eastern Mau Forest coupled with human encroachment of the forestland as well as intensive agricultural activities, tonnes of soil, heavy logs and tree branches have found their way into the lake.

"The silt is what is choking the lake," a concerned Warutere says and adds, "it is worrisome and if this goes on unchecked, we will have no lake in a generation to come."

Raw sewerage from the neighbouring estates is also a major threat not only to the lake but also to the flora and fauna resident in the park.

"The sewerage system in Nakuru is old and dilapidated," remarks Bernard Kuloba, a KWS research scientist . He says the domestic sewerage works were designed in the 70s when the population in Nakuru was low.

"The population has massively grown and has stretched the main sewer line that runs close to the park, while the fact that it is made of asbestos does not help the situation because it cracks from time to time," adds Kuloba.

However, Simon Kiarie, the Director of Environment at the Nakuru Municipal Council, says that both the Kaloleni and Njoro treatment works are under-utilised. "The two plants are currently working at 19 per cent capacity," he says.

The storm water drainage system in the municipality adds to the myriad of problems of the lake. Most housing estates like Flamingo and Kimathi, adjacent to the park, have had most of their sewerage systems blocked.

"This means that the sewerage, including kitchen waste, seeps into the storm water drainage systems and flows into the storm water retention tanks located within the park," Kuloba says. "Today, the water retention tank is full of not only silt, but kitchen waste as well," he adds.

"When the rains come, water from Milimani, Menengai, the town centre and the neighbouring estates is not retained in the retention tank, but flows onwards into the lake, depositing all sorts of foreign bodies."

Raw sewerage is nitrogenous while the alkaline waters of the lake have plenty of sodium hydrogen carbonate. When the nutrient-rich sewerage seeps into the water body, carbonates are released into the air, thus the water pH remains the same.

However, the nutrient-rich sewerage gives a massive growth boost to the Spirulina plantesis, a species of the blue-green algae on which the lesser flamingoes feed.

This leads to an algal bloom when the algae grow very fast but end up depleting the oxygen in the water due to the very prolific growth. The algae in turn die en masse due to lack of enough oxygen.

Once the Spirulina plantesis dies, two other species of algae multiply. The Anaebena and the Mycroslotis algae are highly toxic when ingested in large numbers.

"So when the flamingoes filter through the plankton, they will mainly feed on these two toxic algae leading to massive deaths," Kuloba states.

Fertilizers rich in phosphates and nitrogen also cause the algal bloom. Farmers upstream use most of these fertilizers and pesticides as do villagers close to the forest and river banks.

The presence of heavy metals like lead from nearby factories within the municipality is also posing a threat to survival of life in the park.

However, Kuloba disputes the contention that flamingoes at the lake are dying due to high pollution levels. "Lake Bogoria has got high nickel levels than Lake Nakuru, yet there are no industries close by," he says.

He reveals that geologists have discovered faulty lines within the municipality and in the larger central rift area. "This, we believe, explains the presence of such metals in the lakes."

The park authorities are also campaigning to have the London dumping site on the upper outskirts of the town relocated to a site in Soysambu within the Delamere Estate. They argue that floodwaters wash debris from the dumpsite into the lake.

"With a loan from the French Development Agency (AFD), we intend to start the relocation in March, 2005," says Kiarie who says that they also intend to put up a modem sanitary landfill as a joint venture with Delamere Estates. The relocation will cost the council over Sh700 million and will better manage waste collection.

"We will be sorting waste at the source before proceeding with recycling and disposal of the same," says Kiarie.

Over 180 tonnes of waste is generated in the town per day - that is over 65,000 tonnes of garbage per year - in Nakuru. The council only manages to collect a paltry 35 per cent of the garbage.

"We are now targeting the informal settlements in Kaptembwa and Pwani areas where waste collection, drainage and sewerage systems are virtually inexistent," Kiarie states.

The newly created department of environment will also help monitor sources of pollution within the municipality and in Lake Nakuru. The department is working in partnership with the Japan International Cooperation Agency (JICA) to put up an educational and research centre at the Lake Nakuru National Park.

The Municipal Council of Nakuru is the first town in Kenya to spearhead an initiative for improving environmental planning and management for the benefit of its citizens, dubbed The Localising Agenda 21.

"This initiative works towards more sustainable urban development of the town, whereby a wide range of action plans are implemented and supported by the UN Habitat and funded by the Belgian Government," Kiarie adds.

These action plans include the revitalization of the council's public housing stock, revitalization of space use around the bus station and market area, environmental planning of the of the geologically sensitive western part of the town, and improvement of solid waste management (SWM).

However, since he came to the park eight months ago, Warutere has been involved in a massive community awareness campaign within the Nakuru Municipality as well as in community settlements close to the Mau Forest.

"We are trying to instil a sense of ownership. People will try to protect what they own and will manage it efficiently. Poor management of our resources is destroying the environment," he cautions. "Our education unit is helping interpret nature to the masses and how best to maintain their survival as well as using it to raise their standards of living," he adds passionately.

The philosophy of understanding, appreciating and accepting the concept of environmental ownership and protection started over three years ago.

"We are aggressively informing the public on the role they should play to avert the disaster to come," says he, and adds that they also encourage tree planting by giving out free seedlings.

On February 16, 2001, the Government of Kenya announced its intention of excising 35,301 hectares of the Eastern Mau Forest Reserve. This took effect in October 2001 through legal notice 142 appearing in the October 19, 2001 issue of the Kenya Gazette Supplement.

The effects of wanton destruction of Mau Forest, the lake's water catchment area, coupled with the adverse effects of global warming and drought, are now being felt because fresh waters flowing into the lake have been depleted.

Most of the rivers flowing into the lake have either dried up or have been trickling into the lake at reduced volumes. River Larmudiac from the Mau Forest has been completely choked by silt and is no longer flowing above the ground into the lake.

This means that animals like the rhino and buffalo are unable to access clean drinking water. The flamingoes, too, need clean drinking water as so do the pelicans.

Through an extensive tour of the park, the stark reality of the gravity of the matter hits home. The area along the lakeshore is littered with all sorts of domestic waste. From supermarket plastic bags, to washing powder sachets and footbalResidents in a Rush to Kill Lakel boots.

The mouth of the River Njoro is as narrow as two meters in width and a depth not exceeding six inches. The delta is a muddy patch, which the flamingoes find uncomfortable.

"This is the bare reality and gravity of the situation. We need to move fast to change this or we will lose the lake and the entire ecosystem within a generation," Warutere remarks plainly.

'Time has come for us to start thinking about future generations. Our greed is destroying our environment and we should change this attitude," he concludes.