Mapping of water resources in large river basins is often hampered by limited ground data. With the introduction of daily satellite observations the operational monitoring of water resources has made a big leap forwards.

WaterWatch developed a flood forecasting and monitoring tool is based on collected real time data sets, without use of any hydrological simulation models. Most flood monitoring tools are based on optical remote sesning, and thus only observe the floods under cloud-free conditions. The new methodology of WaterWatch is based on microwave remote sensing, which also provides flood observations under cloudy conditions.

The flood forecasting and monitoring tool includes several components:

• identification of the flood prone areas;
• flood mapping using soil moisture, soil moisture changes, and local rainfall;
• flood predictions using soil moisture, local and upstream rainfall; and
• flood impact mapping (damages and benefits) using vegetation indices.