Flood Defence Plans (FDP)
The aim of a Flood Defence Plan is to serve as a guide for an active protection against flooding, primarily through a combination of low permanent embankments and higher temporary barriers that are only erected when necessary. The permanent structures may be ordinary waterfront or riverside streets and bike lanes, with a known minimum height. They also serve as the reliable foundation for the temporary barriers. The plan is based upon a very accurate flood map, which in turn is based upon data from an airborne laser scanning of the area.

In cooperation with the GIS-development organization Future Position X in Gävle we have developed a model for a Flood Defence Plan (FDP), targeting a wastewater treatment plant in Eskilstuna. Before, the entire plant was regarded as exposed to a flood threat, but the plan showed that only a part of the plant was in fact threatened, and that those buildings and installations could easily be protected by a 150 metre long temporary flood barrier. This meant that the threat to the rest of the plant could be lifted.

Recently a second FDP was completed. This time the objective was to plan how to defend Gysinge bruk, a beautiful cultural heritage village, from the waters of river Dalälven. Also Gysinge turned out to be defendable, by a combination of low levees and temporary barriers.

Both Flood Defence Plans are downloadable from here (in Swedish):

Ekeby wastewater treatment plant
Gysinge bruk

The Tubewall and the Boxwall
Terra Firma developed the "tubewall", a mobile flood protection barrier that is both light and stable. It consists of a number of air-inflated plastic tubes, interconnected like a chain, and is automatically anchored by the weight of the flood water! Some years ago the patents were transferred to NOAQ Flood Protection AB, which is now selling the product world-wide.