STOCKAGE A LA SOURCE - WWF Belgium

Recensement des actions de stockage de l’eau en amont des bassins hydrographiques
EXECUTIVE SUMMARY
1. Global water issue
The last decades, water resources on the planet have decreased in an uninterrupted
way, considering the quality and quantity parameters. It’s becoming harder today to
meet everyone’s needs in fresh water. Among the 35 millions km 3 of fresh water in the
world, only 1% is located in the lakes, rivers and the various wetlands. Moreover, fresh
water isn’t equally geographically distributed through the different regions of the
globe.
The lack of fresh water resources is a fatality for many living beings and ecosystems
worldwide. Water management is now essential considering the crucial role of water in
human survival. However, lack of water isn’t the only issue to manage as even in
tempered regions, issues linked to water management occur periodically.
In our countries, more and more flood-connected problems arise during strong rainfalls
which lead some rivers to reach the point of saturation. This surplus water typically
causes the floods. Most water evacuation developments only put off the problem
downstream. In summer, it’s the issues linked to low water levels that occur. Even
though less spectacular and little highlighted in the news, those are not less
problematic.
It should also be noted that hydrographical basins feature areas with particularly good
water retention capacities. Nevertheless, due to a modified soil usage and to an
intensive exploitation of wetlands (peat bogs drainage), this absorption role has nearly
disappeared in most of the hydrographical basins.
Most of present policies and general opinion still tend to think that the measures to be
taken should aim at evacuating fresh water downstream as fast as possible. Rivers have
often been conversed, canalized, enlarged and diverted, thus increasing population and
goods vulnerability. Policies delay starting to concretize sustainable projects. Not such
a long time ago, many dykes have been developed in the Netherlands or raised in
Flanders. Rivers beds have been enlarged and deepened (The Netherlands and
Wallonia) and meanders have been eliminated in Wallonia.
2. Objectives and framework of this work
The aim of this training course, in the Fresh Water Unit of the World Wide Fund for
Nature (WWF), is to produce an experiments collection document about fresh water
management. It will provide detailed information over fresh water conservation and
management actions conducted by environmental and ecological organisations. The
objective is to make local politicians, eco-councillors, farmers and managers become
conscious of the existence of examples of actions in the field of storage at source, and
of the possibilities to implement those at a local level (on catchment areas, near rivers
and in wetlands).
For a few years, the WWF is searching solutions that could be alternative and
complement existing downstream facilities (alluvial plains restoration, rivers
recovery…). The storage at source concept has been generalized by the WWF in
collaboration with a consultance agency (the Ark Foundation) through a work entitled
“Storage at source, less floods during high water periods; more water during drought
periods” (Overmars & al., 2003). The WWF has allowed Natagora, the RNOB/BNVS
and the Ark Foundation to introduce water retention increase measures in the
RNOB/BVNS nature reserve in the East of Belgium.
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