Pump Stations

In early 2010 two 1.2m Wastop® non return valves were fitted at KGV pumping station outfall pipes in Dundee.  The valves, supplied by Aquatic Control Engineering Ltd, were needed to stop tidal waters from the River Tay from entering the pumping station and to avoid putting added pressure on the already installed penstock.

United Utilities who service the Scottish Water pumping station approached ACE Ltd for a solution. The Wastop® non-return valves were ideal for this application, they could easily be installed in the existing pipes and were constructed from 316 stainless steel therefore ideal for marine use.

The Wastop®s were installed by USL diving contractors of Great Yarmouth and were floated in using buoyancy bags so there was no need for scaffolding or de-watering the surrounding area. The valves were installed in two days and were instantly operational.

After Installation was completed Stuart Rice of United Utilities Operational Services said, “We have already noticed a drop in pumping station sump levels due to the valves operating capabilities in not allowing the tidal River Tay to ingress into the pumping station.  As the sump levels are lower than normal this allows the station pumps to operate on level controls thus saving on electrical power. This saving is an added bonus as the valves were initially installed to allow UUOS safe operation of the emergency bypass valve located at the pumping station.

One of Stockholms oldest storm water pump stations which lifted water a few meters was built with two metal flap valves. The flap valves didn’t function particularly well and leaked water back into the pump when the pump was not running. This lead to high repair costs, and meant that the pump ran much more than necessary leading to higher energy usage.

Every time the pump stopped the metal flap valves slammed shut causing irritation to local residents due to its location in a residential area.  Wapro was contracted to construct a WaStop® with a diameter of one meter. The existing opening and flange was measured and a customised WaStop was built to suit the preexisting conditions. The WaStop® was shorter than standard and the flange was placed in the middle of the valve to allow

installation without an alterations to the existing building.

The WaStop® valve has now been in operation since 2006 and has required no repairs. It seals 100% and makes no sound when closing. WaStop valves have much lower head loss than traditional flap valves and

despite this are able to cope with a back pressure of 5 meters.

The Thames Gateway is a Central Government priority area for regeneration and growth, and stretches along the River Thames from the City of London eastwards through Thurrock and Bexley and on to Southend in Essex and Sheerness in Kent. Over the next 20 years, 120,000 new homes will be built and 180,000 new jobs will be created. The Environment Agency have constructed two large pumping stations and refurbished a tidal sluice as part of ongoing works to improve flood alleviation in the local area.  These pumping stations provide a significant level of flood protection to large areas of Barking and Dagenham.

ACE has consulted closely with Halcrow and the Environment Agency to provide an alternative solution to the original specification for these pumping stations.  The original concept outlined a stainless steel flap valve solution, requiring maintenance and lifting equipment for inspections and repairs.  The supply and design of six WaStop in-line non-return valves were provided following our consultation, which were not only cheaper than the external style valve, but offered lower maintenance, in-pipe protection for the membrane and importantly, a greater ease of installation.  The simplicity of installation incorporated into the design allowed for Interserve to construct the project without the need for our Installation and Project management team to be present.  Three of the WaStops placed in the Beam River pumping station measuring 1400mm in diameter, were the largest WaStops to have been made at the time of project, the three WaStops at Gores Brook are 1000mm in diameter.

ACE would like to thank, Halcrow, Interserve and the Environment Agency for this opportunity and for their professional scheme management throughout.”