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Watershed Management
Watersheds are drainage or catchment areas where fresh mountain water gathers and flows downstream to feed rivers and lakes, before running into the ocean. More than half of the world’s population depends directly on these mountain watersheds for water to grow food, generate energy and, most importantly, to drink.
Yet, over the last three decades, these upland watersheds have come under increasing threat. Pressure from population growth, deforestation, mining, unsound agricultural practices, global warming, tourism and urbanization are all taking their toll on mountain watersheds…and putting the supply of the world’s freshwater at risk.
Watersheds that are damaged pose serious problems to environments and peoples, both upstream and downstream. The cost of this damage can be seen in eroded soil, landslides, diminished water quality and quantity, loss of biodiversity and severe ecological balances. Degraded watersheds are among the greatest constraints to sustainable development. The need for the careful management and use of watersheds — ‘watershed management’ — has never been greater.
Making the most of what we have
Watershed management means putting in place systems that ensure land resources are conserved and used sustainably now and for future generations. The watershed management approach brings together various aspects of forestry, agriculture, hydrology, ecology, soils, climatology and other sciences to find ways of conserving and using land resources.
But watershed management is more than natural science methods and tools. It is a continuous and participatory process that recognizes and involves local people — in both upstream and downstream areas — and aims to help them improve their livelihoods without harming their environments.
Starting at the top
Whatever happens in upland watersheds has a massive impact on downstream areas, which include many of the world’s biggest cities, in both developed and developing countries. Many past attempts to develop and conserve watersheds have tended to overlook people living in the uplands and highlands. But the health of the entire watershed depends on preventing environmental degradation in these areas.
Here, populations are amongst the poorest and most disadvantaged in the developing world. Poverty, isolation, growing population and limited access to land are forcing many upland peoples to adopt farming and survival practices that damage the environment.
Excessive livestock grazing, tree felling and the cultivation of marginal lands are leading to deforestation, erosion and the loss of biomass. The effects can be seen in destructive torrents, flooding of valuable agricultural lands downstream, poor groundwater recharge, and the sedimentation of reservoirs and irrigation infrastructure.
If watershed management is to be effective on the international scale, sound water and land management practices must be adopted at the local level in upstream mountains and highlands.
Building partnerships to conserve a vital resource
Conflicting interests over water use are often local in scale. In southern Ecuador, the Machangara river basin supports industrial, agricultural, hydro-electricity and human needs for an area of about 325 km2, before draining into the Amazon watershed. But growing demands on declining resources have led to water rationing and conflict. A watershed council has been set up to resolve conflict by coordinating actions among different water users. The council also implements agriculture projects in upstream areas, which are helping to control sedimentation and other land-use related problems.
In the agricultural Cauca Valley of southwest Colombia, large-scale farmers and sugarcane producers — worried about losing their essential water supply — decided to fund watershed management initiatives themselves. Projects and plans for upstream areas are developed by the regional environmental authority (the Cauca Valley Corporation) and paid for from the membership fees of voluntary associations of water users. Fees are based on the amount of water each user consumes. There are now 12 of such associations paying for activities to protect forests, conserve vegetation cover, increase water flows and stabilize discharges during the rainy season.
Looking toward the next generation of watershed management
Watershed management and its benefits are attracting increasing attention around the world. However, the last systematic, global-scale assessment of watershed management strategies and approaches was carried out in 1985, and many of the same problems and constraints it found still exist today.
In 2002, FAO launched the initiative, ‘The Next Generation of Watershed Management Programmes’, to provide a platform for information exchange and to offer advice and support for the implementation of effective watershed management at the local, national and regional levels. To date, it has carried out a key actors’ survey, a stocktaking review of FAO’s experiences, a case study analysis and regional workshops. Guidelines will shortly be developed and findings disseminated to relevant international organizations, national institutions and decision-makers, as well as watershed management specialists and researchers. The final outcome is expected to build the foundation for increasing consensus, developing future plans and strategies, guiding policy development, and orienting research in watershed management.
Understanding the links between forests and water
Forested catchments are vital for the ecological health of the world. They shelter immense biodiversity, provide food and fodder and are important sources of forest products. Importantly, forests also protect mountain watersheds. Yet, we need to better understand the crucial relationship between forests and water if we are to improve the management of freshwater resources for both upstream and downstream users.
In November 2002, forest and watershed experts from 18 countries and 16 international organizations met in Shiga, Japan to review the current state of knowledge and future needs for a better understanding of forests’ role in alleviating poverty and providing drinking water, food security, and other socio-economic and environmental benefits.
The meeting adopted the Shiga Declaration on Forests and Water which recommended that governments and other stakeholders develop policies and implement programmes to promote holistic approaches that link forests, water, watersheds, the environment and people.
Promoting integrated watershed development programmes through the effective participation of local people is key to preventing further ecological imbalance. An integrated approach is needed for conserving, upgrading and using land, water, plant, animal and human resources.
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