- The more remote the path, the more stringently
the criteria for path repairs should be applied. This will be
a matter of judgement but in general, the more remote or wild
the location the less acceptable an obviously engineered path
will be.
- Repaired paths should be suitable to
the route’s use and constructed on a scale appropriate for
the intended use as a footpath, bridleway or byway.
- The use of way marks, cairns or other
intrusive features, other than those traditionally established
on summits and path junctions, will be discouraged.
- A sustained commitment of resources to
path management will mean that small-scale continuous maintenance
can replace infrequent, major repairs as the normal method of
path management.
Adapted from ‘Repairing Upland Path Erosion - a best practice
guide’ (1996) by Peter Davies and Jim Loxham with Gill Huggon
with support and endorsement from the British Mountaineering Council,
Camping and Outdoor Leisure Association, Council for National
Parks, Countryside Commission, Countryside Council for Wales,
Mountaineering Council for Scotland, National Trust for Scotland,
Ramblers Association and Scottish Natural Heritage and accepted
and adopted by the House of Commons Environment Select Committee.
Download our fact
sheet giving an overview of path restoration in the Peak District.
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There are a number of approaches to tackling
path erosion. Before work commences, full consideration is given
to issues such as remoteness, sensitivity of wildlife or archaeology,
aesthetics and wider recreation management issues.
The various technical approaches available
are:
i. Stone pitching
Stone pitching is the preferred technique for repairing eroding
paths on steep ground throughout the uplands of Britain. It has
been successfully used on a number of sites on the Pennine Way in
the Dark Peak on slopes of between 15 and 30 degrees, where the
vegetation and much of the soil had been lost to trampling and resultant
water action, leaving a path of loose gravel and boulders. A good
stone-pitched path provides a stable and comfortable surface for
walkers whilst reducing the visual scar considerably.
Stone pitching consists of positioning large
blocks of undressed local stone on the path line to create a series
of irregular steps up the eroded slope. Where suitable stone is
not available in situ, nearby screes, old quarry spoil or even abandoned
drystone walls may provide a source. The stones are dug into the
subsoil with a flat face uppermost and wedged together to give mutual
strength. Any gaps are filled and then covered with soil. Drainage
channels are incorporated into the design and the finished path
surface should rise smoothly without an abrupt change of gradient,
blending naturally into the hillside. The sides of the erosion scar
are landscaped and turved, and the whole area seeded with a nurse
crop mix.
ii. Causey paths
The traditional method of laying stone flags, locally known as ‘causey’
paths, has recently been revived to repair eroded footpaths in deep
peat in the Pennines - fifteen kilometres of causey path has been
laid on the Pennine Way in the Peak Park since 199. This technique,
developed centuries ago to improve transport links for the packhorse
trains across the Pennines, has many advantages and has proved popular
with walkers as a pleasant walking surface, landowners for the appearance
and durability and conservationists for the rate of adjacent habitat
recovery. The reasons for this are:
- The geology of the stone is native to
the southern Pennines. This blends well into the moorland setting,
and does not have the e adverse effect on vegetation which non-native
stone may have by the leaching of minerals.
- The flags are recycled from demolition
sites. They are therefore relatively cheap and do not have the
impact on the local environment of newly quarried stone.
- The reclaimed stone has the benefits
of 150 years of ageing, which gives it a weathered look, and provides
a hardened patina making it more durable. The unevenness of the
hewn surface provides good grip even in wet weather.
- The flags can be laid directly on the
eroded peat surface without the need for an underlay, because
o the size of the stone spreads the surface area loading. This
minimises cost and eliminates the need to bring man-made materials
onto the moor.
- Unlike unconsolidated aggregate, the
solid stone flag does not suffer from surface washout by rainwater.
This minimises the need for drainage works, such as ditching,
which alter the natural water flow and can lower the water table.
It also reduces the need for maintenance.
- Small watercourses across the path can
be crossed using longer flags, without pipes or other intrusive
engineering structures.
- The estimated life span of a maintained
flag-path is twice that of aggregate and ten times that of wooden
boardwalk.
Causey paths have been most successful at
repairing paths crossing the blanket mires at gradients of less
than 5 degrees. However flagstones have also been successfully employed
on badly eroded mineral soils and on gradients of up to 10 degrees.
iii. Machine repairs
to mineral soil paths
Where a damaged stretch of path cuts through free-draining mineral
subsoils on a gradient of less than 15 degrees it is possible to
reduce the erosion scar and provide a reasonably sustainable path
by carrying out landscaping and drainage work with a mini-digger.
The aim of this technique is to prevent
further soil loss and provide a sustainable walking surface using
the existing exposed mineral subsoil as the path surface. The erosion
scar is reduced to a path width of about 1.5 metres by re-vegetatation
and stabilisation of the sides of the path. These goals are achieved
in a number of ways:
- reprofiling and levelling the eroded
path surface
- providing adequate drainage of the path
by ditching and culverts
- cambering to ensure any surface water
is taken off the path and not allowed to run along the surface.
- blocking off multiple walk-lines with
turfs and boulders
- seeding the new path sides and ditch.
This technique has the advantage of being
extremely cheap, since little surfacing material is imported (some
stone may be required for culverts) and labour costs are minimal.
The minimum use of materials ensures that, with care, the finished
path will have a natural look. It does however depend on careful
analysis of the sub-soil to ensure the path surface will be free
draining and durable.
iv. Hand-working
on remote sites
Some very remote sites need the impact of recreation to be reduced
by careful management of the path to reduce the width of damage
or the number of braided lines, and prevent further deterioration,
whilst avoiding intrusive engineered solutions. It may also be important
not to encourage use by appearing to make remote sites easier to
negotiate. A number of methods have been employed to solve these
problems, loosely bracketed together as 'hand-work'. These include:
- Drainage. This controls the action of
water as boggy paths deteriorate more rapidly, causing people
to spread out laterally and surfaces to scour.
- The technique commonly known as ‘cut
and fill’ is based around the construction of a ditch on
the uphill side of the path to prevent water flowing onto the
route and using the spoil from the ditch to create a suitable,
sustainable surface to the footpath.
- Realignment. Some subtle realigning of
the path onto more durable ground by the positioning of boulders
or turf banks to block off damaged routes
- Surfacing of short stretches will be
necessary to firm the path surface and keep people on the desired
route- this can be achieved by gathering nearby stone and gravel
to produce a natural-looking path.
- Re-vegetation. If re-vegetation work
is thought appropriate, localised addition of seed and fertiliser
and transplanted vegetation can be used to establish and maintain
a healthy sward and begin the process of re-vegetation.
The use of personnel skilled in upland construction
techniques is vital. The work is labour-intensive, but few materials
need to be imported. The result will be a narrower path with reduced
impact which retains a natural appearance in keeping with the landscape,
but which can sustain current levels of use.
Aggregates
Aggregates have only rarely been used to repair footpaths in the
Peak District. However, gritstone aggregate has been used where
either:
The soil is too clay or organic to use as
a path surface, or;
The slope is too steep for flagstones but not steep enough for pitching.
In the above cases unsorted gritstone aggregates
have been mixed with the subsoil and compacted, to create a consolidated
surface. This technique is quite different from the use of sorted
aggregates of non-native geology, laid on geo-textile, which is
now considered to be unsuitable.
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