Fen Management Handbook - Scottish Natural Heritage

11.6.3 Path construction
Paths built on mineral soils, either outside the fen, or on banks within it can be
built using any of the standard footpath construction techniques, and are generally
cheaper, more durable and less environmentally sensitive than paths on peat.
– Paths should be designed and constructed to allow continued water movement.
Where necessary, culverts should be included.
– Hard paths made of mineral soil or dried peat may allow nutrients to be released,
and marine peat may create acidity, so it is important to monitor surrounding
vegetation to look for adverse impacts. Avoid the use of inappropriate material
e.g. limestone on an acid site.
– Paths built on wet peat or peaty soils are more difficult to construct and more
susceptible to damage and erosion, but less than perfect conditions underfoot
can also be self-limiting on levels of use. The RSPB site at Strumpshaw Fen
(see case study at the end of this section) and the Norfolk Wildlife Trust site at
Ranworth are good examples.
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Experience of path construction on fens
– At Hickling Broad the Norfolk Wildlife Trust is moving from
boardwalks to paths built on peaty banks made from spoil left
over from other management work. The peat is allowed to dry and
stabilise, and the path is then built using mineral hoggin (compactable
mix of stone and fines) to provide a dry and more robust surface. This
type of path should be able to accommodate current visitor numbers
of 8-10,000 per year, but might not be able to withstand a sudden
increase or influx of visitors.
– Upton Broad has an undisturbed peat surface on which paths made
of plastic mesh with sown grass were planned. Plant growth within
the mesh was poor, so instead a “corduroy” path has been used,
composed of 50 mm recycled plastic battens separated by 10-20 mm
to allow vegetation growth. The plastic becomes embedded in the
peat and vegetation, and at this site water levels are stable so there is
no danger of the path floating away in a flood.
– In the valley fens of the Little Ouse headwaters the local conservation
project (see detailed case study at the end of this section) has used
3 cm plastic Netlon Turfguard mesh to protect the soil surface.
Although slippery when first laid the mesh quickly becomes overgrown
with vegetation and provides a strong and stable path that can be
mown. It is less suitable in shaded areas where sparse plant growth
leaves the mesh exposed. Compared with the original peat surface
it is particularly resilient to baby-buggies and wheelchairs. Some
maintenance is required where the mesh curls at the edges, and
mesh-surfaced paths have not proved to be suitable in areas with
grazing animals. In fact both horses and cattle have caused problems
at these sites as they show an inclination to use paths and bridges,
causing damage by deep poaching. Those involved with the site
report that sheep seem to be less of a worry, because they are lighter
and are often removed earlier in the winter.