The fully inflated "Balgstuw" at Ramspol, The Netherlands
Due to persisting winds (with forces eight to nine Beaufort) on Thursday it was decided to inflate the storm surge barrier at Ramspol. The process was started shortly after midnight. It took about one hour before the enormous barrier was fully inflated thus protecting the Ramspoldiep for high water in the Ijsselmeer.
During recent weeks the water levels in the major rivers changed from extremely low to very high. There is currently no danger for flooding, but flood plains and several embankments have been flooded.
The rapidly rising water levels are caused by continuous rainfall, especially in the German basin and saturated land, preventing rainwater to penetrate into the soil.
The storm surge barrier near Ramspol, designed and built by the BAM Group nv, was built to project the hinterland against flooding by high water from the IJsselmeer lake. It was commissioned end 2002.
The barrier consists of three inflatable, nylon-reinforced rubber dams, each 75 m long, 13 m wide and with a design height of 8.35 m. They are the largest dams of their kind ever built. The dam is inflated with air while a gravity-feed system allows water to flow in. The barrier is lowered again by pumping out the water and letting out the air.
The video below shows how the surge barrier works:
Facts & Figures
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Situated 4,65 m under NAP (Normaal Amsterdams Peil)
- Maximum height of the dam 3,55 m above NAP
- Height 10 m
- Length down 60 m, above 80 m
- Threshold width 15,4 m
- Length fabric 24,3 m
- Capacity dam: air 3.500.000 liter, water 3.500.000 liter
- Thickness fabric 1,6 cm
- Production Bridgestone, Japan
- Weight fabric 19,3 kg/m2
- Weight dam 33 tons
- Minimal lifetime fabric 25 year
- Closing time max. 60 min.
- Time to empty max. 180 min.
- Closing water level + 0.50 NAP
The storm surge barrier during inflation.