CONSERVATION

30 JULY - SEPTEMBER 2019 CONSERVATION

hat water is the essence of life developed and implemented the is both a familiar cliché and REDD+ Project. This project specifically aims an inescapable truth. Such is to reduce carbon emissions from deforestation the importance of water that across the Chyulus landscape to generate carbon Section 43(d) of the Kenyan credits being sold on the international carbon Constitution says that “every markets. Between them, these organisations person has the right to clean have been remarkably successful in conserving and safe water in adequate quantities” With the Chyulu Hills landscape even though there increasingT threats to water security, Kenya is are significant threats and there has been some recognising the vital role played by its upland deforestation and loss of wildlife. BELOW: The areas, many now designated as “water towers” water stored in As a water tower, the Chyulu Hills are an through the Kenya Water Towers Bill (2018). the Chyulus is important water catchment with its most visible The Chyulus water tower is one of the more equivalent to a manifestation being the sparkling and clear water encouraging stories. Gazetted as a national park lake 10km long by that bubbles up at Mzima Springs. Although there in 1983, the southern boundary borders 3 km wide by 20m are a number of springs around the Chyulus, West National Park. Part of the eastern side has deep. recent modelling of the aquifer suggests that 80- the Kibwezi Forest Reserve, owned by Kenya 90 per cent of the total water captured emerges Forest Service and managed by the Sheldrick through Mzima. Wildlife Trust. The western flank is protected by the four AS A WATER TOWER, THE CHYULU Maasai group ranches, Kuku, Kuku A, Mbirikani and Rombo, all of which have undertaken HILLS ARE AN IMPORTANT WATER conservation programmes in partnership with CATCHMENT WITH ITS MOST two NGOs, the Maasai Wilderness Conservation Trust and . VISIBLE MANIFESTATION BEING THE These nine organisations formed a partnership, SPARKLING AND CLEAR WATER THAT formalised as trustees of the Chyulu Hills Conservation Trust (CHCT) that successfully BUBBLES UP AT MZIMA SPRINGS

JULY - SEPTEMBER 2019 31 The Chyulu Hills rise up to a height of about TOP: World one-third of total current supply. From available 7000 ft at the highest summits to create a rainfall famous hippo pools data, the total average outflow from Mzima has gradient ranging from 1200 -1700mm to 300- formed by water remained remarkably constant over the past 400mm at the lower altitudes. The height of the from the Mzima 70 years at about 3.8 m3 per second (cm/s) (= hills and the forest cover also creates conditions Springs. Bubbling 328,000 cm3 per day) with a total variation over that promote cloud formation and interception, forth from the the years in the range of about 2.5 -5.5 cms. promoting the growth of the dense moist cloud Chyulu Hills Lagged multiple regression analysis shows that forest along the ridges. volcanic boulders variation in spring flow is most highly correlated The geology of the Chyulus, characterised is a famous site in with rainfall occurring 3-4 years earlier but there Tsavo West, Mzima by recent permeable volcanic lavas overlaying is also a correlation with rainfall up to 10 years Springs, where impermeable early pre-Cambrian rocks, results in earlier. This shows that the Chyulus are in fact 225 million litres most of the rain and cloud moisture percolating like a giant sponge creating a huge underground of water a day down and then flowing along with the impervious reservoir that stores incoming water and releases feed into crystal layer, emerging to create the oasis of Mzima it at a very constant rate. clear pools that are and other minor springs. Importantly, the home to crocodile So how much water is stored in those green recharge process of the Chyulu aquifer shows and hippo. The hills? Given that Mzima accounts for 80 per cent the importance of forest and vegetation cover in water may take of the total flows, it is possible to calculate the preventing run-off, maintaining the integrity of 4 years to reach total outflow across the whole aquifer. This is 4.75 the aquifer and its ability to maintain its spring Mzima after the cm/s. If it is assumed that the average retention outflows. initial rainfall on period is 4 years then the aquifer is storing about In the latter half of the 1950s, the pipeline the hill tops. 600 million cubic metres. How much water is from Mzima to supply Mombasa with water was that? A bathtub or Lake Victoria? The answer constructed. Now, some 60 years later, the Mzima is a lake about 10km long, 3km wide and 20 pipeline provides a critical contribution to the metres deep. That is about the surface area of water budget for Mombasa, accounting for about but 20 metres deep rather than 1-2

32 JULY - SEPTEMBER 2019 conservation and to increase its predictability. In this context, the strategy is to develop a portfolio of Payments for Ecosystem Services (PES). In addition to ecotourism, other environmental “rents” such as payments for conservancies and compensation for livestock losses to predators, metres. And this remarkable reservoir was all TOP: Chyulu Hills and carbon payments through REDD+, it seems constructed by nature: no infrastructure and no landscape with appropriate that the value of aquifer protection World Bank loan! forested summits should be recognised through payment by Interestingly, the catchment area for the Chyulu and grasslands and water users. Such an approach for payments for aquifer is almost one hundred per cent overlain woodlands on the water is entirely consistent with the statutory by the project area of the REDD+ project. This slopes. functions of national water towers legislation means that the REDD+ project and the Trustee that include “establish a framework for payment organisations of the Chyulu Hills Conservation INSERT: Chyulu is a for environmental services for the purpose Trust that own the REDD+ project are protecting corridor for animals of sustainable management of water towers that live in Tsavo the forest and surrounding habitats and are by ecosystems.” and Amboseli. default also the guardians of the Chyulu aquifer. The logic for receiving some payment from The park shelters Such conservation is of course not without cost Mombasa water users is inescapable but one a wide variety of and yet in the 60 years since the Mzima pipeline question is pricing. Currently, bulk water is wildlife and huge has been in operation, Mombasa water users have delivered down the Mzima pipeline to the Coast concentrations of not paid a single shilling towards conservation plains game such as Water Service Board (CWSB), which pays nothing of the Chyulu landscape and support for its local wildebeest, zebra towards catchment and aquifer protection. CWSB communities. Meanwhile, the CHCT trustee and eland as well sells bulk water to Mombasa Water Supply and organisations are raising at least $5 million per as elephants which Sanitation Company (MOWASCO) for 20 KES year for conservation of this landscape. The normally wander in per cubic metre. MOWASCO provides treatment vision developed by the CHCT and its Project from neighbouring and the infrastructure for delivery of the water Office, the Maasai Wilderness Conservation Amboseli. to the end consumers and charges an average of Trust, is to expand funding for Chyulu landscape 101 KES per cubic metre though the price can

JULY - SEPTEMBER 2019 33 vary between 35 and 240 KES depending on the Mzima Springs are infrastructures, such as dams or desalination, category of user and the volume consumed. a series of four Chyulu water will continue to be a critically If a payment of 50 per cent of the price paid natural springs and important resource for the coast region, and by MOWASCO to CWSB is used as a guideline, one of the biggest in comparison to other sources it is pure, this equates to 10 KES per cubic metre. If attractions in Tsavo predictable, cheap, and climate change resilient! the Mzima pipeline is delivering at its design West. The source The Chyulu water tower provides Kenya with capacity of 35,000 cubic metres per day then this of the springs is a an ideal test case for water PES. Since Mzima is payment would be just over 125,000,000 KES natural reservoir delivering water reliably every hour of every day, ($1.25million) per year. This would represent under the Chyulu the only barriers to implementation are political, Hills to the north. a significant and fair contribution towards legal, financial, and institutional. The Chyulu The Chyulu range ensuring the future integrity of the aquifer. The Hills Conservation Trust already provides the is composed of Chyulu water is especially valuable because it institutional structure to receive and distribute volcanic lava rock is also the cleanest and purest water from any PES payments for catchment conservation. With which is porous, of Mombasa’s supply sources and only requires the appropriate will and collaboration between so rain water simple chlorination. percolates down the government, CHCT partners, and downstream Currently, Mombasa has a water deficit. through the rock, water users, appropriate legal and financial Although there are plans to expand the off-take spending years structures can be developed, using models from a from Mzima with a second pipeline, this would underground number of countries around the world. not be sufficient to meet the coastal regions before emerging The total costs for such an implementation rapidly growing projected demand. The major kilometres away at would likely not be more than $1 million. For an project to significantly increase supply is the Mzima. annual return of $1.25 million that represents building of the Mwache dam to the south of a pretty attractive investment for securing an Mombasa. Over 60 metres high, the dam is important part of the future water supply for estimated to cost $150 million. Even with such Kenya’s second largest city and its surrounding major new projects to increase supply with new areas.

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