Location: Semple St Porirua, New Zealand 

Client: Porirua District Council 

Problem: Due to an insufficient drop in the stormwater outlet running into the harbour, high tides and periods of heavy rain was causing backflow up the outlet pipe, which resulted in surface flooding of the low-lying areas around the city centre. 

Solution: A 1300mm flanged WaStop valve was installed in the stormwater outlet pipe to prevent tidal floodwaters from entering the stormwater system and enable the pipe system to be used for stormwater retention during high tides.  

Design: A 1300mm Stainless steel WaStop valve with a rear nest flange to position the valve in the pipe and a full-face flange to secure the valve to the pipe end. 

Thanks to Hygrade Products New Zealand for supplying this information. www.hygrade.net.nz