Stormcrate Offers Stormwater Solution At New Primary School - continued
Helen Wilson of Forkers commented:
For this new build school, the StormCrates met our requirements perfectly and were used to create an underground tank that could hold rainwater. Incredibly strong and needing only minimal cover, they are the ideal solution for managing surface water run-off.
Weighing only 18 kg per module and measuring 1200 mm x 600 mm x 420 mm, the modular units can be easily lifted by hand and then laid or stacked in rows. The units are suitable for a range of applications including residential, commercial and industrial projects.
The modules can be wrapped in a geotextile which allows stored water to slowly seep into the surrounding ground and back into the water table. A more common practice, is to wrap in an impermeable geomembrane to create a sealed underground tank.
The sealed tank approach was adopted at the new primary school, with the outlet from the tank then controlled to facilitate a slow release of the stored water back into the drainage system over a longer period.
Manufactured from recycled plastic, they have a high void ratio of 95% which means that each crate is capable of storing up to 300 litres of water in the event of heavy rains. If inspection is required for future maintenance, then Brett Martin can offer StormCrate Inspect Crates.
There are no limits on the use and design of the surface over the system and they may be successfully installed under parking areas, driveways and landscaped areas. Ideal for domestic soakaways, only 250 mm of cover is required above the crates for driveway applications which results in less dig and site spoil.
For more challenging applications the lorry bearing design ensures extreme load capacity due to StormCrates stable column structure which provides a SLW 60-bearability with a 500mm covering which represents a vehicle of up to 60t.
Kijlstra Delivers First CSO Chamber To Welsh Water
Principal contractor Morgan Sindall choose Kijlstra’s precast option for Welsh Water project and has installed the first combined sewer overflow (CSO) chamber for Welsh Water on a site in Maesteg, south Wales.
The 3.5 m long, 2 m wide and 2.1 m deep precast concrete chamber was installed as part of Morgan Sindall’s AMP6 framework contract with Welsh Water.
The works involved installation of the new precast CSO chamber plus mechanical screen and associate pipelines and manholes. The 17 tonne CSO chamber was manufactured off-site and installed using a 60 tonne capacity mobile crane.
This was followed by the two tonne internal weir wall, grouted in place once the chamber had been positioned within its excavation. The CSO riser unit, weighing another seven tonnes, was then lifted into place on top of the base unit.
Preparation works in advance of the chamber’s delivery included construction of a 5 m x 4 m x 3 m cofferdam and a concrete blinding slab.
Morgan Sindall’s site agent Mark Thomas said the precast option was chosen after careful consideration of all the alternatives.
We basically had three options - in-situ concrete, a plastic chamber or precast. Precast was the way forward for a number of reasons
Morgan Sindall chose the precast option to eliminate and minimise risks associated with a traditional in-situ pour - including working at height, steel fixing, manual handling and concrete works.
As well as the health and safety benefits, the precast option also saved time on the overall programme, effectively reducing the 12 days required for in-situ concrete to just one day to install Kijlstra’s factory-finished product.