Waste Transfer Stations, Newark and Worksop

Background:-
Clugston Construction was charged with building two UK based waste transfer stations for French owned Veolia. When HBPW was asked to become the lead designer for its large shed-like schemes in Newark and Worksop it was an opportunity to prove that value engineering really can make a difference.

Challenge
Both sites comprised large steel clad buildings, each with a 5-metre-high concrete wall to its perimeter. The buildings, located on brown field sites, had a history of industrial use, meaning that innovation was necessary to accommodate and retain all excavations arising on site. Soil contaminated from historical use can be costly to transport so careful planning of ground levels at both locations ensured that little if any removal of soil was necessary.

Planning Conditions for the new facilities meant that any water flowing from the sites would need to be restricted to less than the existing flows, through use of water attenuation. Typically this involves excavating soil to install large underground holding tanks so that in the event of a heavy downpour, water can be collected, stored and subsequently drained away into existing sewers in a more controlled way. A more innovative approach was required.

Solution
HBPW chose to design above ground water storage on top of the surrounding external yards. By having the external yards set to gradients that effectively form large ponds, it meant that in the event of a heavy rain, storm water could be stored ‘on top’ of each yard. Effectively an area of each site becomes temporarily flooded, but in a controlled manner, meaning operations at either of the facilities, or their neighbouring properties, are not affected. Also, by removing the need for large excavations for underground tanks, the removal of potentially contaminated soil from the site has also been avoided. There were even greater savings at the Newark waste transfer site where surplus water flows into a nearby stream. Had HBPW opted for underground tanks, the difference in levels between the stream and the base of the tank would have required a pumping station. However, as water is now stored at ground level, gravity is utilised to discharge water into the stream, saving even more money.

Outcome
Innovative engineering by HBPW resulted in significant savings thanks to a practical approach to overcoming challenges on both sites, and providing enough storage to deal with the worst possible downpour within a 100-year period.