LULLY: FLOODS OF NOVEMBER, 2002: QUICK REMINDER

The village of Lully is exposed to three sources of flood risk: rapid rises in the level of the River Aire; a high piezometric level of the surface aquifer; and runoff water from agricultural land further up the hillside. In addition, there are several aggravating circumstances: Lower Lully constitutes a small basin, in which run-off water collects without any natural drainage into the river; houses were built with inhabitable basements (in spite of not being permitted by local building regulations); and numerous alterations had seriously diminished the capacity of a collecting drain. Following heavy rainfall in the morning of 15 November 2002, the Lower Lully basin was flooded by a build-up of run-off water, as the main drain was blocked by a sharp rise in the level of the River Aire. In fact, the potential dangers had been revealed in March 2001 by a smaller flood that had occurred for exactly the same reasons. Ultimately, the damage was only of a material nature (flooded houses and apartment buildings, leading to evacuations and re-housing of families), but the outcome could have been far more tragic, given that some residents slept in the basement, and were woken up only by the water flooding in.

Local firemen had already been called out during the day on 14 November to bail out a flooded underground car park. Having been called out again at around 3am, they were already at the scene when a further rise in water level caused the ditches1 around the basements of the newest houses to burst. Even though the area was under water at that stage, the emergency services did not think it necessary to order a complete evacuation because they were unaware that the house basements were inhabited. Consequently, the safety of residents was put at risk, due to the misapprehension that building regulations in the affected housing would have been followed. While the developers had marketed and sold the basements of the worst-affected housing as living space, planning permission had been granted without the breach in building regulations being detected. Furthermore, a previous opportunity to identify this risk – when excavations for the planned housing had been flooded in 2001 – had also been missed.

ACCESS THE LULLY SPACE-TIME EXPLORER

For more on this event, see November, V., Penelas, M., and P. Viot (2009). “When flood risk transforms a territory: the Lully effect”, In Geography, vol. 94.

VISUALIZATION’S PURPOSES

First, we have highlighted the risk as evaluated by the interviewed actors: it reveals the multiple knowledge that exists on risks in time, before, during and after the event; it gives also insights of the different practises in time and their spatial impacts (general evolution of laws, management tools, etc.).

Second, we established links between facts, actors (human, administration, lobby groups) and "non-humans" components (schemes; laws; planning, reports, etc.), in order to understand the dynamic of risk in time and space. Risk here is not only described by the outline of the phenomena in a vulnerable site, but also by its dependence upon stakeholders, some hidden or forgotten elements of the territory (drainage system, previous inundations, etc.), and the general evolution of the society (new management tools, measures, laws, knowledge, etc.).

ACCESS THE LULLY SPACE-TIME EXPLORER

ACTORS’ DESCRIPTION

In the time line, actors’ categories are classified according the smallest common denominator between all of them. But in each of these categories, one may find actors with different characteristics

Non-Human actors

Human actors

Actor’s real names are hidden for anonymity reasons.