This also has an effect on flood prevention, for which in future more retention zones will be needed. Many former wetlands were turned into settlement areas, industrial zones and sporting grounds as a result of improper zoning; when they can no longer be restored to their original condition, the creation of new retention zones in close proximity to residential areas will gain importance.

This also needs to be seen in context with the provisions of the EU Floods Directive, which puts a ban on the common practice of quickly draining off the floodwater to downstream communities. While the creation of new retention zones is relatively easy in Austria’s east with its vast plains, such areas are much harder to find in the western and southern regions of the country where mountain ranges abound.

The example of Tyrol shows exceptionally well how much the interests of urban and economic development, road construction, forestry, agriculture and farming, and – last but not least – flood prevention are clashing. There is a particular interest in exploiting the potential that still exists in forestry and agriculture.

A case in point is the community of St. Johann. Because of the rapid population growth in this community, a civil engineering firm was retained to review existing zoning along the local rivers (“Reither Ache” and “Fieberbrunner Ache”). The best (and cheapest) option according to the review was to convert some blocks of arable land at the community’s outskirts (24 and 17 hectares) into a flood retention zone.

The farmers, fearing they might lose their arable land, sought assistance from scientists (also visit the website https://forschung.boku.ac. at), regional press and legal advisers, which resulted in other optional zones further upstream to be taken into account in planning.

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(Source: aqua press Int. 2/2009, Mag. Christof Hahn)