Home - Effluent Diffuser Systems - Flexible Risers, Elbows, Crosses

Protect the outfall from damage

Problem

Solution

    Outfall diffuser pipes often have riser pipes that protrude above the bottom of the river, ocean or lake. They discharge at some distance above the bottom to ensure the jets do not discharge into the sediment and the height above bottom must account for potential movement of the bottom sediments from ambient sediment transport caused by currents and waves. The problem with metal or plastic riser pipes is they can be easily broken when hit or snagged by boat anchors, trawls, nets, and submerged debris. If they break below the river or sea bed, sediment intrudes into the outfall pipe which can reduce the hydraulic capacity and dilution efficiency.

    Red Valve fabricates TFD’s with integral wire-reinforced rubber risers, elbows and custom styles such as tees and crosses. They are flexible and extremely rugged and are designed to “deflect and return” when hit by anchors or debris. This prevents sediment intrusion and prevents damage to the outfall thereby eliminating the need for outfall clean out and repair costs. The riser mating flanges can be located just below the river or seabed to minimize the risk of snagging. They are available in the slip-on, circular-flanged, or square-flanged mounting configurations.

    TFD’s can be fabricated with integral risers or elbows or a combination of both. Custom tee and cross configurations are available.

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    (5) 8” Series 35D’s with integral wire-reinforced rubber 45 degree elbows installed on a pulp and paper outfall diffuser in Mississippi.

    (4) 200mm Series 35D’s with integral wire-reinforced rubber risers installed on a 450 mm diameter, 20 meter long diffuser pipe. Outfall installed in on an icy river in British Columbia, Canada. Photo courtesy Ivo Van Bastelaere.

    24”x16” and 18”x12” TFD’s in wire-reinforced rubber cross configurations were installed by divers on an outfall in the Chesapeake Bay. The outfall had open RCP riser pipes and was continually getting clogged with sediment.

US Patent No. 6,367,505
Canada Patent No. 2,366,605