Mismanagement of natural resources gives us no margin of error to handle an increasingly unpredictable climate

Photo © World Bank/    Tree planting: Professor Wangari    Maathai with Johannes Zutt

I spent yesterday in rural Kenya with the World Development Report (WDR) team and the inspirational activist Professor Wangari Maathai, the 2004 Nobel Peace Prize laureate. Professor Maathai graphically showed us the problems across multiple areas of the economy when the climate does not behave as predicted. The visit powerfully demonstrated how much worse the effects are when the changing climate combines with a poorly managed environment. Only 1.7 percent of Kenya's territory has forest cover, compared to about 10 percent a century ago. And the forests are increasingly fragmented. Yet these fragments protect water towers that are the source of the country’s rivers. The diverse natural forests regulate rainfall, provide homes for Kenya's stunningly diverse flora and fauna, and of course they also help our planet to store carbon. But human activity in and around the forests continues to threaten their survival. Over recent decades, plantation forests have replaced much of the natural forests that once covered Kenya, but they are much less effective at regulating rain, preventing soil erosion and protecting diversity. As I said on our visit to the Aberdare Forest yesterday, in many places I did not see forests; what I saw instead were tree farms.

With about 80 percent of its territory consisting of arid and semi-arid lands, the bulk of Kenya's population—about 70 percent—lives around the five large forests that are also Kenya's water towers—the catchment areas for almost all of Kenya's rivers. With the forests under threat, the rivers are threatened too—and Kenyans struggle harder to obtain drinking water, irrigate their crops, water their animals, drive their industries, and generate sufficient power (over 60 percent of Kenya's power is hydroelectric). Population growth is combining with climate change to put tremendous pressure on Kenya's already fragile environment. Yesterday, we saw farmers growing their crops on steep un-terraced slopes, and cultivating increasingly small plots. We met a farmer who had 1.5 acres of land to support 13 people. In many cases, yields were low, crops were struggling on marginal land, and denuded soils were completely exposed to the upcoming el Nino rains, which will undoubtedly carry much of that soil into Kenya's rivers and dams. Prof Maathai, echoing some key messages from the WDR, told us how diverse cropping, together with good soil management and "greenbelting" plots with multiple species of indigenous trees would allow Kenya's agricultural land to be farmed more intensively, leading to better yields and less pressure on the forests.

Yesterday we also saw the destructive impacts resulting from rapid urban growth, poor land management, and a failure to protect Kenya's forested water towers when we visited the Ndakaini dam outside Thika. The reservoir behind this dam supplies 80 percent of Nairobi’s water, and it now holds only one-third of its capacity. It is discharging 1 m³/second, compared to the 5m³/second it was designed for, but it is recharging at an even slower pace—of about 0.13 m³/second. That is why Nairobi’s water is rationed today. But it’s not just about our water. Our ability to generate hydroelectric power is also affected. The Ndakaini dam was designed to have a 1.3 MW turbine, but it was never installed because the water flow proved to be too unreliable. A series of failed rains are key to the current problem, of course, but we have compounded the problems with our wasteful use of the resources available to us. With the forests disappearing, the flow of water diminishes, and it also contains much more soil, which ends up as a silt deposit on the floor of the reservoir, diminishing its capacity and shortening its life. This year in Nairobi, we see all too clearly why environmental considerations must be at the heart of all of our development activities, and also why we need to take a long view that encompasses the entire landscape.