Tideflex the answer to Woodstown Woes

Tideflex the Answer to Woodstown Woes

This stormwater outfall on a beach near Woodstown, Co. Waterford was proving very problematic with the existing flap valve solution unable to cope with the constant shifting of beach sand. MeasurIT proposed a solution which was installed in 2014 and is operating effectively. 

Project Details

Client: Waterford County Council
Design Details: 1No. DN600 and 2No. DN150 S35-1  Tideflex valves bolted to a S/S plate

The existing stormwater box culvert outfall at Woodstown Strand was not functioning as intended - often being completely covered as the sea washes sand up on to the beach, or sometimes wedged open with sand or debris. Unfortunately, both the historical metal round flap valve (the frame was still bolted to the headwall) and the current stainless steel plate flap valve, were unable to cope with these conditions. The stormwater therefore could not drain out of the outfall and built up in the upstream system, causing problems in the upstream catchment.

Outfall buried beneach beach sand to the top of the headwall

Outfall buried beneach beach sand to the top of the headwall

Flap valve excavated for inspection by a JCB

Flap valve excavated for inspection by a JCB

This arrangement was never going to be a practical long term solution

This arrangement was never going to be a practical long term solution

MeasurIT proposed a more robust solution that we believe will function maintenance-free for decades. Since the exit drain is a box culvert with internal dimensions 700x760mm we proposed a stainless steel mounting plate bolted to the headwall to cover the existing outfall ope, with 3No. S35-1 flanged flat-bottomed Tideflex duckbill valves (1xDN600 and 2xDN150) bolted to it to maximise the flow through the square outfall culvert.

Tideflex valves working as designed

Tideflex valves working as designed

Obviously the sand situation will not be a problem for the Tideflex duckbill valve, which has been proven over many years to be self-clearing of sand in similar situations.