Warwickslade Cutting Railway

The Warwickslade Cutting Railway was a light railway temporarily built to fill in the Warwickslade Cutting, a straight drainage ditch dug circa 1850 in the New Forest of south-east England, with imported gravel and clay. In 2009, the Forestry Commission decided to obliterate it and replace it by a more natural meandering stream.

The reason for the works was that Warwickslade Lawn Site of Special Scientific Interest (SSSI) was "in an unfavourable declining condition because the artificially deepened cutting meant that there was no seasonal inundation of the grassland and woodland habitats". Surprisingly, much of the course of the original, pre-1850s, stream could still be seen on the ground. The aim of the works was to reinstate the original stream as closely as possible, whilst filling in the Cutting. It was necessary to bring in 10,000 tonnes of hoggin to fill in the cutting, plus some clay to make plugs to ensure that water followed the desired course.

The contractors were Alaska Environmental Contracting. They used 8, 13 and 18 tonne hydraulic excavators, 10 tonne rubber tracked dumper trucks and an innovative light railway.

To bring in 10,000 tonnes of hoggin would have required 1,000 round trips for a Morooka MST-2200vd tracked dumper truck. The contractors Alaska designed and built an experimental light railway from a forest track to the cutting. By this they reduced the compaction of the soil of the forest by eliminating heavy dumper movements. This allowed work to continue even in wet weather. It also resulted in lower fuel consumption and less noise and pollution. The project cost of £214,500 included plant hire and labour (£106,500) and infill materials (£108,000).

The track laying began on 2 September 2009 along a wide, grassy forest track. The track consisted of circular steel pipe of about 6mm wall thickness, welded to steel cross members which were in turn bolted to wooden sleepers. One side was fitted with a steel spike to engage with the next section. Thus, it fitted together very much like a toy railway, using preassembled track sections which are either straight or of fixed curvature. The track laying operation looked a bit like a child’s train set on a large scale. The rails, with sleepers ready attached, came in sections - straight or curved to suit their position. The tube and pin joints fitted together exactly as do the rail sections of the toy set.

The purpose of the railway was to reduce the environmental impact of bringing so much material on site. The Morooka dumper truck has an engine of 250 HP whereas Alaska thought that they could shift the same 10 tonnes of gravel in a train powered by a Boxer 532DX mini-skid, a tracked vehicle running on the rails, which has a 32 HP engine. Thus the emissions savings would be substantial. There ought also to be less surface damage. The railtrack had a calculated ground pressure, when loaded by a train carrying a load of 10 tonnes, of under 3 psi, to avoid the sleepers sinking into the occasionally very wet ground. Therefore, no ballast was needed.

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Wikipedia