Monday, March 19, 2018 Exploring the nature of resilience: A trip down Kenya’s Athi River

UN Environment promotes the use of nature-based solutions this World Water Day.

故事

The Athi River starts in the iconic Ngong Hills that rise above Nairobi. It flows past the bustling metropolis and through Kenya’s largest national park, Tsavo East, until it finally reaches the Indian Ocean. The river, its tributaries and riverbanks are the source of irrigation and drinking water for millions of people, and wildlife. Its water and riverside also underpin a number of industries in the region, including mining and tourism.

However, a local environmental group, the Explorer’s Club of Kenya, is concerned about this important river system. Signs are strong that human activity and pollution are overriding the river’s natural capacity to provide clean water for purposes such as drinking, agriculture or wildlife habitat. In some places, farmers have abandoned their fields, and certain species of birds and other wildlife are noticeably absent.

The group organized a walking expedition along the river to find out more about the state of its waters, and document potential sources of its pollution to find solutions to reverse the degradation.

Athi River solid waste
In some places, solid waste lines the banks of Kenya's Athi River. (Explorer's Club of Kenya)

“What we saw and learnt,” says the club’s founder, Alberto Borges, “was very upsetting. Athi River was filthy, stinky and had deep green-coloured water with litter strewn all over its banks. A very different scene compared to 15 years ago.”

On the first part of the journey, beginning at its source covering the uppermost third of the river, the club’s members noticed inflows of raw sewage, chemicals and wastewater, as well as large amounts of solid waste including plastic bags and bottles, tyres, glass, and scrap metal fragments.

“Local governments can protect waterbodies by keeping alive the riparian vegetation which acts as a water filter, stabilizes the river bank, and regulates the water temperature by providing shade.”

The Nairobi River, a tributary of the Athi River which passes through several densely populated areas, is one of the major contributors to pollution within the Athi River ecosystem. Near the Nairobi suburb of Kamulu they observed extensive sand-mining, which has further disturbed and eroded the riverbed ecosystem. Clearly, Athi River is losing its natural balance.

Seeking nature-saving solutions

The theme for World Water Day on 22 March is “The Answer is in Nature”. The theme is meant to highlight how we can harness solutions that already exist in nature to reduce water pollution and natural disasters such as floods and droughts.

“There are many ways in which we can support the natural capacity of the river to recover,” says UN Environment water quality expert Kilian Christ.

“These include preventing further wastewater from flowing into it and preserving a natural riverbed which supports aeration, thereby helping the river to clean itself. Local governments can protect waterbodies by keeping alive the riparian vegetation which acts as a water filter, stabilizes the river bank and regulates the water temperature by providing shade.”

Along these lines, the Explorer’s Club of Kenya made a number of recommendations for protecting and restoring the Athi River, including:

·       Stopping any untreated chemical or industrial waste and raw sewage from reaching the river.

·       Treating chemical/industrial waste at source by using more biodegradable products.

·       Expanding and upgrading the sewage treatment ponds at Ruai, Nairobi, as they can no longer effectively treat the volume of sewage.

·       Installing proper solid waste management facilities in all settlements around Nairobi; sort and recycle rubbish to prevent it ending up in the river; and

·       Regulating sand-harvesting activities along Athi River.

Kenya took a major symbolic step in the right direction in August 2017 by joining a number of other countries in banning or taxing plastic bags, many of which had found their way into the country’s lakes and rivers. Supermarkets no longer provide any plastic bags, although they are still illegally used by some fruit and vegetable vendors.

Sand harvesting Athi
Sand harvesting along the Athi River (Explorer's Club of Kenya)

The UN Environment International Environmental Technology Centre (IETC) is also working to support environmentally sound improvements in Athi River. The Athi River Export Processing Zone is one of the three pilot sites identified as part of a large project developed by IETC and funded by the Green Climate Fund. The project aims to "green" existing and upcoming industrial parks in Kenya - including those along the Athi River - by promoting a shift to environmentally sound practices, with a focus on reducing and better managing waste. The project will work also with local communities to stimulate the creation of green micro-businesses.

“Anything that UN Environment does to support freshwater ecosystems by using the mechanisms already in our nature can be called nature-based solutions,” says UN Environment freshwater expert Yeonju Jeong. “Examples are reforestation, grasslands restoration, preservation of peatlands, conservation agriculture, wetland construction (like artificial wetlands used for wastewater treatment) and wetlands restoration.”

Together with UNESCO and the Convention on Biological Diversity, UN Environment is leading the 2018 World Water Day campaign. The organization is also a contributing author of the 2018 UN World Water Development Report, on the related topic of Nature-based solutions for water.

The report will be launched on 19 March at the World Water Forum, in Brasilia, Brazil.

#BeatPlasticPollution is the theme of World Environment Day 2018.

For further information Yeonju.Jeong@un.org

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