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Dyrhoff offers three products: air-inflated rubber dams, water-filled rubber dams and spillway gates.

All of these products offer the following benefits over other technologies:

  • They typically have a lower cost than other automated solutions.

  • They can be manually deflated if needed; they cannot jam closed and cause flooding.

  • They can cover long single spans.

    • Rubber dams can cover up to 100m per span.

    • The longest spillway gate covers a span of 300m.

  • They have a low waterline profile with no need for a gantry, so are less obtrusive than products such as radial gates. We have even supplied our dams and gates for their architectural appeal.

  • They are easy to install and maintain.

  • They require no lubrication.

Which Product?

We are often asked which of our products is most suitable for a particular project.

Air-inflated rubber dams have the advantage of being quick to inflate and are often the most cost effective option. An air inflated rubber dam is generally operated in two positions: open or closed. Whilst small adjustments are possible, it does not give much further control over upstream water elevation. The maximum overtopping of a standard design air-inflated rubber dam is 20% greater than the height of the dam.

Water-filled dams are generally slower to fill than air inflated dams. They are better suited to situations where there is a tail water elevation and provide some control over upstream water levels. Overtopping of 50% of the dam height is achievable with a water-filled dam.

In situations where there is tail water, a combined air-water dam might also be suitable.

Spillway gates offer the benefits of a rubber dam but with the additional protection of an overlying steel gate panel. This can protect the inflated bladders against debris and vibration where there are strong currents.

Spillway gates also allow full control over the upstream water elevation; they can operate in any position from fully open to fully closed.