Barcelona's coastal location and the proximity of the
surrounding coastal mountain ranges leads to frequent flash flooding in the
region. The channelisation of Barcelona's two main rivers, the BesÚs and
Llobregat rivers has greatly reduced the flood risk in the city. Many of the
seasonal rivers on the outskirts of the city continue to pose flood risks,
however. Successful fieldwork can be undertaken in dry river beds using evidence
of previous flood levels as the basis for calculating velocity and discharge
A normally dry river channel nearSant
Pere de Ribeshas evidence of a past flood level line in a river cliff.
This level can be used to measure the channel cross-section and with Manning's n
formula, the approximate discharge for the flood event. Further
downstream, housing developments and a camp site are located adjacent to the
river channel. Bank-full discharge can be calculated at this site using the same
techniques and the flood risk assessed.
River studies can thus be combined with Hazard Management
For reliable and safe source-to-mouth 'wet' river studies, it
is necessary to travel a short distance north of the city, where the Tordera and
Tenes rivers provide unspoilt and little-visited locations.
Travelling further afield, spectacular waterfalls, gorges and
rapids can be studied in the Collsacabra region, less than two hour's drive to
the north of Barcelona. This study can be incorporated within a walk
through the Collsacabra region or include a visit to unusual deep meandering
wadis en route.