The Promise of the Western End[Published 1990]
|Early narrowboat Seagull uncovered in Brickworks Arm.|
|THE CASE FOR RESTORATION|
|Ch. 1 Introduction|
|Ch. 2 The Demand for Leisure and Recreation Facilities|
|Ch. 3 The Canal: Future Use|
|Ch. 4 The Benefits of Restoration|
|THE PROPOSED RESTORATION PLAN|
|Ch. 5 A Brief History|
|Ch. 6 Present Condition|
|Ch. 7 Resources for Restoration|
|Ch. 8 Restoration Proposal|
|Ch. 9 Protecting the Bats|
|Ch. 10 Work Programme|
|Ch. 11 The Estimated Costs|
|Appendix 1 Map|
|Appendix 2 The Surrey and Hampshire Canal Society Ltd.|
|Appendix 3 Recommended Additional Reading|
|Appendix 4 The Basingstoke Canal - Information and Statistics|
|Author||Stan Meller - Special Projects Group Manager|
Philip Riley BSc (Econ)|
David Junkison BSc RIBA
|Photographs||Geoffrey D. Helliwell|
|Drawings and Maps||David Meller BSc (Hons) MIHT|
|Angling Notes||Andre Grandjean|
|Natural History||Charles Cuthbert BEd MSc|
Eastrop Bridge repaired by Hampshire CC in 1989.
A centre page pictorial spread, featuring Basingstoke, appeared in a national Sunday newspaper in the 1930's showing glimpses of the then small market town and of its industries. A small amount of text appeared, acclaiming the facilities that existed at the time, referring to Basingstoke's connection with London by road, rail and water, the latter referring to the Basingstoke Canal.
The writer must have worked from an old guide book for no direct waterway link with London, via the Wey Navigation and the Thames, had been possible for over 25 years. The last attempt to navigate to Basingstoke was made in 1914. Strenuous efforts were needed beyond Greywell to force a way through the stagnant water, choked with weeds, and a channel which had virtually dried up in places. The files of the Hants and Berks Gazette relate how, after being trapped for some weeks the narrowboat, aptly named Basingstoke, was towed into the basin where the Basingstoke bus station stands today.
Since those far off days, I have studied the history of Basingstoke and have always regretted that broken link with the Thames. I was filled with indignation when I learned that the deep channel at Old Basing, had been filled in to provide a site for houses. What we in Basingstoke had lost, and what could have been such an asset for the many thousands of Londoners arriving through the overspill scheme, became very apparent in the mid-1960's when I was engaged in assisting to compile a book on the economic future of Basingstoke.
It is therefore a great pleasure to write this foreword to the proposals made in this booklet which has been so well researched and given the apt title The Promise of the Western End. If the promise the Basingstoke Canal holds by being restored westward is realised, then the advantages that will accrue will be enormous. Unfortunately the length to be made available is only some 1-1/4 miles.
Stan Meller deserves every congratulation for the text which is so informative, and the result of many hours of study. The case for extending restoration is very convincing and the proposal is supported by the solid achievement, over the years, of the Surrey and Hampshire Canal Society and the county councils through whose territories the canal flows.
It is so heartening to learn that there is such a dedicated body of volunteers to call upon to help with the mammoth task of removing fallen trees, clearing rubbish, restoring brickwork, etc., and to learn that there are other canal associations with similar followings ready to pool their resources. It is also reassuring to know that so much research has gone into how Greywell Tunnel can be restored with the colony of bats given full consideration on a 'tunnel sharing' basis, with the construction of additional tunnels to relocate them if necessary. Naturalists must be impressed when they read this.
To make the canal navigable to Penney Bridge will extend the waterway's amenities for the ever increasing population of Basingstoke and surrounding villages. A towpath to provide walks in beautiful surroundings; the opportunity for boating and for picnics beside the canal; to be able to study flora and fauna — and being so lavishly endowed with trees, what a paradise it could be for bird lovers. The restored canal could be stocked with fish to enable anglers to cast a line in local waters rather than having to travel to places well away from Basingstoke.
Unfortunately, the construction of the M3 prevents the Basingstoke Canal being reopened to allow a passage to the original basin off Lower Wote Street, Basingstoke. But The Promise of the Western End, if achieved, will open up part of the way and when it comes to added amenities — the whole way.
Arthur Attwood, Basingstoke. January 1990.
Arthur Attwood is a regular contributor of historical articles to the Basingstoke Gazette.
It has always been an objective of the Surrey and Hampshire Canal Society to restore Greywell Tunnel and the canal westwards as far as possible. This aim was set out in the Society's booklet Basingstoke Canal — The Case For Restoration, published in 1966. Anticipating that the whole of the canal from New Haw to Greywell will be re-opened to full navigation in 1990, the Society feels that now is the time to consider further restoration.
The Society believes that restoration westwards from Greywell should be undertaken for a number of important reasons. These include the provision of additional leisure and recreational facilities for the local community and to create a suitable terminus at the western end of the canal. The re-opening of a further part of the canal would also add to its tourism potential, whilst restoration of Greywell Tunnel would preserve a feature of considerable historical interest. Restoration would also present a number of possible ways to increase the canal's existing source of water supply which is limited to three or four million gallons a day.
This study examines a proposal to extend restoration to the site of Penney Bridge on the Greywell Road, west of Up Nately. The advantages of the proposed extension are discussed, as are some of the problems to be overcome. Restoration work undertaken and promoted by the Society to date is reviewed and this clearly demonstrates the capability of volunteers to carry out some of the work described in this proposal. The Society is generally acknowledged to be one of the leading canal restoration organisations in Britain.
Our proposals are not necessarily intended to be the final stage in the renovation of the canal. Further restoration of the canal westward of Penney Bridge is technically possible, but would present greater difficulties. In any event the investigations required to draw up a viable proposal are outside the terms of reference of this study.
Members of the Society already possess the skills required to solve the engineering problems associated with the restoration of the canal line. As regards Greywell Tunnel, the work required is of a more complex nature and would involve external consultants and contractors.
The Society has a team of professional engineers, qualified in the appropriate disciplines, who have examined the condition of the structure. A report of their findings, together with a detailed feasibility study for restoration, has been submitted to Hampshire County Council, together with a recommended procedure if a restoration policy is agreed.
A fully detailed engineering proposal will be submitted to Hampshire County Council as a supplement to this study. Accordingly, only a small section is included to deal in general terms with engineering requirements.
Comments on the contents of this study will be welcomed by the Society and should be sent to the Honorary Secretary:
The Demand for Leisure and Recreation Facilities
In recent years there has been a significant increase in the amount of leisure time available to an increasing number of people. This trend is expected to continue in the years to come. In turn, this has led to more pressure on the facilities available for leisure and recreation.
Basingstoke is an expanding town and would, we believe, welcome restoration of the canal to the west of Greywell because of its close proximity.
There are plans to develop Hook as a residential area which will further increase demand for the kind of popular recreational facilities a waterway offers.
At a local level, the derelict remains of the former navigation is not only a wasted resource but also an eyesore. Restoration would make a significant contribution towards enhancing the attractiveness of the local environment, create a useful new recreational amenity and regenerate a more diverse aquatic ecology west of Greywell.
Extending restoration, including Greywell Tunnel, will also enhance the attraction of the canal to visitors. Tourism is a fast growing industry, estimated to be worth approximately £30 million annually in Hart, Basingstoke and Deane and Rushmoor local authority areas alone. One reason for this rapid growth is the mushrooming interest in Britain's heritage of which inland waterways are an important part.
Restoration of the canal to a standard appropriate to normal leisure use can be achieved at a relatively low cost, although the re-opening of Greywell Tunnel will involve a significant amount of expenditure. Once restored, the canal would undoubtedly provide an important amenity in north-east Hampshire. The extension of the canal to Penney Bridge would also provide the opportunity to create a suitable terminus point for the restored waterway.
The Canal: Future Use
Paramount to any future use of the canal west of Greywell is the question of ownership and management.
While the greater part of the canal, from its junction with the River Wey Navigation to Greywell has been in public ownership since the mid 1970's, the length of canal from the western end of Greywell Tunnel to the site of Penney Bridge at Up Nately was retained by the New Basingstoke Canal Company Ltd. whose principal shareholder, Mr. S.E. Cooke, died in 1985.
During 1989, Hampshire County Council disclosed its intention to purchase this length of canal and the transaction was completed on 1st March 1990. It has always been the Society's view that public ownership would be the most satisfactory basis on which to determine the future of the canal west of Greywell, and the initiative taken by Hampshire County Council is therefore warmly welcomed.
To be objective in proposing a plan for the full restoration of the canal as far as Penney Bridge, it is appropriate that other options should be considered, together with the related benefits.
In deciding the future of a derelict canal there are three broad options:
* Leave the canal in its derelict state.
These options are analysed in more detail below.
Leave the Canal Derelict
Furthermore, in the case of the length of canal which is the subject of this study, part of the towpath is a public footpath and the right of way must therefore be maintained. Unless the towpath is cleared and properly maintained, the unchecked growth of trees and subsidence of the cutting walls will ultimately block the right of way completely.
A derelict canal is an attraction to the ubiquitous rubbish tipper. In recent times, the residents of Up Nately formed a working party to clear the Basingstoke Canal locally of a large quantity of rubbish ranging from car engines to plastic bottles. If tipping is allowed to continue unchecked, the canal becomes an extremely hazardous playground for young children, particularly when broken glass is added to the accumulated rubbish.
Between the Brickworks Arm and Brick Kiln Bridge a sewer has been allowed to discharge into the canal. This is a typical example of what can happen when a canal is seriously neglected.
All these factors lead to the inevitable conclusion that there is no reasonable justification for leaving the canal in its present state.
Infilling would involve the construction of culverts and the tipping of large quantities of clean filling material. The current cost of this work, based on figures from British Waterways, is in excess of £100,000 per mile. This figure would not include the considerable costs which would be incurred in providing suitable access for plant and machinery. The Society estimates that the total cost for the whole length would probably be in the order of £250,000.
The Society believes that infilling is neither a viable proposition, nor offers any practical advantages for re-development.
It has been suggested that restoration of the canal's western end, excluding the tunnel, is another option. While the Society accepts that restoring an isolated length would improve the local environment, the resultant 'duck pond' would limit its use for recreation.
The Benefits of Restoration
Restoration not only contributes towards improving the environment of the canal and benefits aquatic wildlife, it also creates a unique recreational amenity confined within a relatively small area.
On completion of restoration, the towpath would form a continuous link from the Greywell Road at Penney Bridge to the River Wey at New Haw. Using the towpath to the north on the River Wey walkers can reach the Thames. To the south the towpath continues through Guildford to Godalming. When the current restoration programme of the Wey and Arun Canal is completed, there is the further exciting possibility of a continuous path over the Sussex Downs to the south coast at Littlehampton.
To the west of Penney Bridge it would seem perfectly feasible, with the co-operation of the Basmgstoke and Deane Borough Council and financial support of the Countryside Commission, to establish a right of way to the outskirts of Basingstoke, creating an important long distance footpath.
The canal is now a popular haunt for anglers and the HBCAA would be willing to extend its activities to cover the restored length west of Greywell.
The length of canal now proposed for restoration offers another mile or so of fishing with the advantage that it is within easy reach of Basingstoke. The re-opening of the canal west of Greywell will help to reduce the growing pressure on other local fisheries. The condition of the channel at present makes angling totally impossible.
A full botanical survey of the canal, including Penney Bridge to Greywell, was published by the Nature Conservancy Council (NCC) in 1988. There are no rare species in this length and the diversity of plants is low compared with other lengths of the canal. However, by restoring the waterway and opening up the long neglected navigation, aquatic plants and creatures will be encouraged to re-colonise the area.
Although commercial carrying ceased long ago, it is still necessary to provide suitable places for larger boats to be turned. In Basingstoke Canal — The Case for Restoration, it was suggested that a new terminus might be created in the vicinity of Little Tunnel Bridge at Mapledurwell. Whilst this location remains an attractive site, a low cost and more practical opportunity to develop a new terminus basin exists at the silted up winding hole which adjoins the Greywell Road at the site of Penney Bridge.
The fact that the canal and the winding hole still exist and contain water, coupled with the immediate road access, are obvious advantages in terms of cost. There is also an adjacent area of flat, level land suitable for enlarging the winding hole and, outside the conservation area, to provide land based facilities. However, this land is not within the area being purchased by Hampshire County Council.
The water area would have to be of a sufficient size to enable a full length canal boat to be turned with ease, and for the provision of some moorings for short periods. Space might also be provided for the hire of rowing boats, skiffs and punts for which there is likely to be a limited demand.
Facilities associated with the canal terminus could include a slipway, toilets and a small car park. A depot to store maintenance equipment would be useful. A canal centre housing a small museum might also be considered.
Built throughout using local bricks, it has the traditional three-brick ring which became the standard specification for nearly all transport tunnels built during the canal era. Its unique history has prompted many requests to arrange inspections of the bore from engineers interested in this type of construction.
The tunnel should be restored as part of our heritage. Restoration is also essential if the tunnel is to be made safe.
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A Brief History
The length of canal proposed for restoration includes Greywell Tunnel and the line westwards to the site of the former Penney Bridge.
This length was first opened for traffic in September 1794 but was closed within six weeks because of subsidence of the cutting at the western portal of the tunnel. The southern face of the cutting, named 'The Slip' on Ordnance Survey maps, was repaired and the channel subsequently re-opened for traffic, but similar problems arose again about ten years later.
At the end of the 19th century the brickworks were developed at Up Nately, near Slades Bridge. Part of the site is now occupied by Heather House and virtually nothing remains of the brickworks except for the Brickworks Arm. This was, in fact, a 91.5m (100 yd) long dock built to accommodate narrowboats and barges to serve the brickworks. Unfortunately the local clay was found to be unsuitable and brick making had ceased by 1910. Consequently commercial traffic on this length of the canal came to an end. Since there was no traffic to provide revenue, no maintenance was carried out beyond Greywell, and the condition of the channel deteriorated.
In 1914 the last commercial boat passed along this length of the canal when the late Mr. A.J. Harmsworth attempted to reach Basingstoke in the narrowboat Basingstoke loaded with five tons of sand. He ran aground at Basing due to lack of water. The attempt was abandoned and there was no further traffic.
From that time onward various land sales and other developments have made significant changes to the canal, which include the demolition of Penney Bridge on the Greywell Road, with a causeway replacing the old structure. As long ago as 1924, Hampshire County Council purchased Brick Kiln Bridge with the intention of eliminating the bridge, replacing it with an embankment and infilling the channel with a causeway. Fortunately this proposal was not implemented.
In the years preceding the second World War, the channel west of Greywell Tunnel was still in use by small pleasure craft. But in 1932 a section of the tunnel roof collapsed, caused by water pressure in a pond above, and a tree fell through. The final and total blockage of the bore by spoil occurred in the early 1950's.
As far as it is known, the last through navigation of the tunnel was made by canoeists about mid-summer in 1950. The accumulation of spoil from the roof fall had by that time built up to the water level. Progress could only be made by 'sledging' the canoe over the mud. The crew had no form of artificial light, other than matches, and were unable to ascertain the situation in the bore at that location.
The whole canal from Greywell Tunnel to the Greywell Road and beyond has been classified as a conservation area. This includes the channel and a margin of land on either side. Thus the canal corridor benefits from certain development controls.
This part of canal was acquired by the New Basingstoke Canal Company Ltd. at an auction sale in 1949.
In order to understand the proposals to restore the western end of the canal, together with the implications, it is necessary to be aware of its current condition.
The present limit of navigation is the River Whitewater winding hole which is of sufficient width to turn a full length 70 ft long narrowboat or barge. The winding hole was dredged some years ago by volunteers using the Society's steam dredger.
From the winding hole to the eastern portal of Greywell Tunnel the channel was dredged by Hampshire County Council (HCC) in the autumn of 1986. This length also includes the gateless remains of Lock 30, built after the construction of the canal was complete. The lock appears to have existed only to hold a small head of water towards Basingstoke, to ease passage through Greywell Tunnel.
The level of water currently seems satisfactory upstream without the lock. As previously mentioned, there may be merit in investigating the possible restoration of the lock, to raise the level of water westwards which could then be used to augment existing water supplies.
There are five ponds situated above the western end of the tunnel. A number of the ponds were formed as a result of earth subsiding into the tunnel. Three ponds hold water and the fourth (centre) pond is dry. The fifth pond appears to be unconnected with the tunnel.
Subsidence caused the western portal to collapse. All the brickwork has been swept away, and the tunnel bore is blocked to a level of approximately one metre (3 ft) below the soffit. Once inside, the tunnel is navigable and the lining appears to be sound for a distance of 201m (220 yds) to the extruded fall.
The plug of spoil in the bore entrance is retaining water at a level higher than navigation requirements. The water level will need to be lowered and the plug removed to enable a further survey of the lining to be undertaken.
West of the Tunnel
The whole length needs a large amount of tree clearance, both dead and growing, deep dredging, towpath reconstruction, and consolidation of the cutting sides.
Eastrop Bridge is still in service and carries foot and light traffic. Following the clearance of trees by Society volunteers, the bridge was repaired by Hampshire County Council in 1988.
From Eastrop Bridge to the junction with the Brickworks Arm, the canal is identifiable as a man-made water course, but is choked with trees, some of which have fallen due to weak support of their root system. The towpath has subsided or eroded in many places and is obstructed by trees. As would be expected, the channel holds water, due to the mainly clay sub-soil.
Slades Bridge is in regular use by domestic service traffic (Heather Lane) and has a metalled surface. The brickwork needs re-pointing. In addition some of the bricks on the south-eastern abutment return, at water level, have blown and need attention soon to avoid further trouble developing. There is a stop plank structure in the bridge hole which seems to serve no purpose other than to form a boundary line or obstruction to navigation.
Some 20m (22 yds) into the dock, on the west side, there is a gap in the bank which allows water to drain off into a ditch. This was thought to be the remains of an overflow weir, but local information revealed that it was formed by a burst in the bank some years ago. The dock adjoins the grounds of 'Heather House', but is owned by the Canal Company.
From the junction at Brickworks Arm to Brick Kiln Bridge the canal is in a deep cutting. It is blocked by a large number of fallen trees and, particularly at the eastern end, the towpath is very badly eroded and obstructed by trees. This end forms part of a public footpath. Part way along there is a strong smell of sewage effluent and it appears that there is an outfall into the channel on the south side. This must be a danger to health and should be eliminated in the near future, certainly before restoration work commences.
A few yards east of Brick Kiln Bridge a sandbag wall has been constructed across the channel to towpath height. A pipe of about 300mm (12 ins) diameter has been built in and there is provision for a control paddle (missing) to prevent water flow in a westerly direction. No water flows through the pipe because the water level in the canal is currently below navigation level, and silt has been deposited to a point just below the bottom of the pipe.
The length of channel from Brick Kiln Bridge to Penney Bridge is in a similar condition to the previous section, but if anything the ravages of nature are more advanced. About half this length is in a shallow cutting. The towpath has degenerated into a beaten track meandering between trees, deviated by subsidence of the cutting sides. The channel can hardly be identified in places due to tree growth and collapse. This section requires tree felling and dredging in common with the previous lengths.
It is not known when Penney Bridge was demolished and the Greywell Road carried across on an improved vertical alignment. A balancing or drainage culvert was built under the causeway apparently to connect the winding hole with the channel still existing west of the causeway. The culvert pipe is visible at the eastern end. The opposite end cannot be traced since the canal bed has been partially filled by rubbish tipping. There is a winding hole adjacent on the east side of the former bridge.
The winding hole is obstructed by trees. They need to be removed, the winding hole dredged and adjacent banks cleared. The culvert must be blocked to eliminate the possibility of water loss.
An unmetalled road has recently been constructed on the north side to lead from the Greywell Road down almost to the edge of the winding hole before turning away east towards an adjacent field.
We have considered available known resources; the potential for acquiring other resources; and how these resources could best be deployed to achieve maximum results, using the most cost effective methods. Resources in this context are assumed to include finance, manpower, plant and supporting services.
In making these proposals, it has been assumed that resources will be made available by the following:
Surrey and Hampshire Canal Society
The Surrey and Hampshire Canal Society has a current income of £40,000 per annum derived from various fund raising activities. This income is applied towards the cost of restoring the canal.
Once restoration of the canal east of Greywell Tunnel is complete, it has been assumed that the Society would be able to allocate a very large percentage of its income to finance the new project. The Society also owns some plant and equipment including concrete mixers, dumper trucks and hand tools.
The Society has among its membership a team of skilled and experienced personnel who have been working for more than fifteen years on all facets of canal restoration including lock, bridge and weir construction, channel dredging, bank protection and ancillary work.
The Society's own skilled work force is supplemented by additional volunteer labour drawn nationwide from membership of the Waterway Recovery Group (WRG) and various other canal societies. WRG is an organisation which can provide a considerable amount of contractors' plant.
It is anticipated that local people may wish to join voluntary working parties organised by the Society, or even organise their own groups.
Hampshire County Council has owned the 16 miles of the canal from Aldershot to Greywell, including Greywell l\mnel, since 1973. HCC budgets each year for a sum required to maintain the canal in a safe and serviceable condition and to carry out improvements. The canal manager has under his immediate control a selection of plant suitable for the task of restoration and maintenance, and has access to other equipment when required. The manager and his staff have long experience and good working relations with the volunteer organisations involved in restoration.
Basingstoke and Deane Borough Council is expected to take a leading role in the restoration of the western end of the canal since it is a major riparian local authority. It is assumed that during the restoration phase, finance to support some of the work, and staff to assist with planning problems that arise, will be made available by the Council.
A further resource for restoration may be available from Government agencies, in the form of training grants. Both the Society and HCC have managed training schemes in the past. For a period of seven years, the Society managed training and employment schemes, which were engaged in the reconstruction of the Deepcut flight of fourteen locks.
In Hampshire the canal manager employed labour sponsored by the Manpower Services Commission to build a very large gabion wall at Dogmersfield, and for several other tasks.
In addition to the resources described above, additional finance may be obtainable from the European Economic Community, the Countryside Commission and the Southern Tourist Board.
The length of canal currently proposed for restoration is considered in two parts.
West of the Tunnel
The following proposals summarise the result of an extensive study, comprising discussion and planning based on experience gained over more than a decade of restoration work, and taking into account the apparent problems.
The major problem for any work west of Greywell is the difficulty in gaining access to the towpath and channel for plant and materials. In order to overcome this difficulty, the Society recommends using a narrow gauge railway line. Such a method provided a successful means of carrying building materials along a mile of track at Deepcut, and again on Ash Embankment where considerable quantities of clay were conveyed by rail to the work site.
Our aim would be to provide tangible benefit to potential users as quickly as possible. We therefore propose that this portion of restoration should be dealt with in two parts: (1) Penney Bridge to Eastrop Bridge and (2) Eastrop Bridge to the tunnel portal. This would enable resources to be concentrated on one length of the canal at a time, in order to re-open it for use as quickly as possible.
Penney Bridge to Eastrop Bridge
The channel needs to be dredged by one of two methods — either dry dredging by a tracked hydraulic powered excavator standing in the channel and loading spoil into bankside transport, or wet dredging by a hydraulic powered excavator mounted in a small hull and loading spoil into bankside transport.
The bankside transport could be the narrow gauge railway system referred to above. We believe that there are sites in the areas adjacent to the canal that may be suitable for spoil disposal.
Eastrop Bridge to the tunnel portal
Unstable ground hi Blisworth threatened collapse in several places and it was decided to replace 900 metres (1000 yds) of lining. A special machine was designed and built inside the tunnel to claw out a whole section of the original brickwork and replace it with pre-cast reinforced concrete panels. Society engineers inspected the work in progress, and concluded that while the solution was admirable for Blisworth it would be totally unsuited to Greywell.
In the case of Harecastle, the solution which was used is considered more appropriate since the problems were very similar. As in the case of Greywell Tunnel, the soffit in Harecastle required local repair. British Waterways placed consecutive contracts to replace failed brickwork and at the same time to reduce the possibility of erosion due to penetration of water from above. This is intended to prolong the life of the repair. Depending on the nature of the subsoU (yet to be confirmed by sampling) this may be the solution for Greywell Tunnel. If this method is chosen, then the ground surrounding the tunnel bore in the location of the failures could be stabilised by pressure grouting before the start of excavation work.
At Crick Tunnel, an original construction shaft, which had been filled in after completion of the tunnel, allowed water to penetrate down to the tunnel lining from above. The infill material continued to settle and caused distortion of the
tunnel lining below. A 10m (33 ft) diameter concrete segment lined shaft was sunk down to and through the canal tunnel. New lengths of concrete segment lined tunnel were constructed, working outwards from this shaft. The concrete lining was then extended across the base of the shaft. Finally the shaft was filled in. In the case of Crick Tunnel, the crown of the tunnel was 18m (57 ft) below ground. In the case of Greywell Tunnel the tunnel roof is a maximum of 10m (33 ft) below the surface.
If either of the solutions adopted for Harecastle or Crick solution is considered suitable for Greywell Tunnel, some initial preparatory work will be required. It will be necessary first to relieve pressure on the parts of the soffit which have failed, to prevent further spoil entering as the bore is cleared. This will involve work on the hill above the tunnel, which is privately owned land, and part of a 330-acre Site of Special Scientific Interest (SSSI), known as Butter Wood, designated in 1986.
The choice of repair method would be decided after boreholes have been sunk in the region of the blocked part of the tunnel.
A well planned programme of work, supported by both the landowner and the Nature Conservancy Council (NCC), must be devised. Considerable deposits of spoil removal will need to be moved with the minimum of environmental disturbance. It may be an advantage to retain the services of an environmental consultant to advise on the nature conservation aspects. However, the work will affect only about 1.8 hectares (4.5 acres), including the canal cutting.
The experience of the Society in undertaking this type of work on other sites is likely to be of considerable value.
Naturalists are opposed to the restoration and re-opening the tunnel for navigation, maintaining that the bats would be disturbed.
A survey of bat occupation in the eastern end of the tunnel, carried out in January 1985, estimated that as many as 2,000 bats may use the bore for hibernation in winter months. Subsequent work has shown this number to be nearer 500. The majority of the bats are believed to restrict their use of the tunnel to the first 366m (400 yds) of the tunnel from the eastern end. Few, if any, bats appear to use the length of tunnel adjacent to the blockage. Furthermore, a check on occupation, made from June to August 1986, has shown that the bats are virtually inactive during the daytime and at dusk. It would appear that the bats have little use for the tunnel during the summer months although a few may use it for roosting late at night.
The bore west of the blockage was entered by an inspection party in August 1985. This was believed to have been the first entry for 10 years. The group included a nature conservancy expert who could find no evidence of occupation by bats at any time of the year.
Deterioration of the bore is accelerating. If the structure is to remain in service, action must be taken soon to halt the process of natural destruction. If this is not done then another major collapse may well take place and possibly trap bats hibernating in the tunnel.
In determining the future of Greywell Tunnel, the Society believes that the following principles must be taken into account:
* The Society has no wish to take any action which would deprive the bats of a suitable place for winter hibernation.
The legal protection afforded by the 1982 Wildlife and Countryside Act and the SSSI is, of course, fully accepted.
• The Society believes that a public right exists at common law to navigate the tunnel with all types of craft. It is also the Society's contention that a statutory right to navigate the canal (including the tunnel) still exists. This right was conferred by the original 1778 Act of Parliament authorising the construction of the canal.
• The tunnel must be regarded as a very important example of industrial archaeology. Its structure and appearance should be preserved and any necessary repair work must be carried out to prevent decay and deterioration of the brick fabric.
• The tunnel is a major source of water for the canal. Appropriate steps must therefore be taken from time to time to keep the springs within the tunnel clear of silt and other obstructions. The channel must also be kept free from impediments to the free flow of water.
Repair of the Tunnel
It will be necessary to construct a dam across the tunnel at the eastern end of the blockage to drain the western end by electric pump. When the dam is built, a sound proof barrier can be continued up to the soffit, thus forming a complete partition between the section occupied by the bats and the area of work. This would form the back of the 'cave', which is believed to be essential for winter hibernation by the bats. The
construction of the barrier would be carried out in the summer months when the tunnel is not in use as a bat roost.
It is proposed that the restoration work would be carried out in one of two ways:
* Either: the cutting outside the western portal would be excavated down to the level of the tunnel invert. The water in the western end would be drained and kept out by pumping. The ponds caused by the tunnel collapse would also be drained. The ground surrounding and below the drained ponds could be stabilised by pressure grouting.
A narrow gauge railway would be laid into the tunnel, and spoil removed by loading into electrically hauled wagons with an air powered loader.
The brickwork would be repaired as the spoil is dug out, moving from west to east.
* Or: repair similar to the work carried out at Crick Tunnel (described above) but using two or three shafts. These would be sunk at the site of the ponds. The ponds would be drained by pumping into a new drainage system laid above the tunnel.
Material would be removed from the tunnel via the shaft and stored around the top of the shaft before back-filling. Each shaft would be sunk, and tunnel repairs completed, before the next shaft was commenced.
All the work, by either method, would be carried out from the western portal. Thus the section known to be occupied by hibernating bats will remain undisturbed. Since all power used will be electric or compressed air, there will be no pollution of the air or brickwork. Working progressively eastwards the last task would be to remove the remaining blockage before breaking through to the dam.
These proposals will mean that, with the exception of the electric pump, any noise created by the work will be reduced to a very low level by the blockage until the point at which the final quantity of material is removed. It is thought that the barrier will damp out the small amount of noise generated by the pump. The break through and removal of the barrier would take place during the summer months.
At that point the restoration of the western end will be complete.
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Use of Greywell Tunnel by bats is not unique. Bats are known to frequent canal tunnels which are navigated regularly. They have been seen for many years in Saddington Tunnel on the Leicester line of the Grand Union Canal, and in Blisworth Tunnel on the main line of the same canal.
We are not aware of any evidence to indicate that the re-opening of Greywell Tunnel would disturb or harm resident bats. But if there are grounds for doubt, we suggest that when restoration is completed, the barrier may be replaced by a removable partition which could be floated into the tunnel in the winter months to recreate the 'cave' environment. This would permit the operation of a time-sharing arrangement whereby the tunnel could be used for navigation in the summer months, and as a roost for bats hi the winter. This concept is described in more detail below.
A notice to boat crews would be published each year informing them of the dates when the tunnel will not be open for navigation.
In the summer the partition would be removed at the western end and the grille opened at the eastern end to allow the tunnel to be used for navigation.
Although this proposal is considered to be workable, it is, at best, a compromise. The tunnel could only be used for navigation for about six summer months and maintenance work could only be carried out in summer.
Separate Bat Tunnel
An ideal site for the bat tunnel exists in the disused chalk quarry situated close to the eastern end of the tunnel. The floor of the quarry, which is fairly flat, is also level with the crown of the canal tunnel. Part of the northern side of the quarry is only 30m (33 yds) from the side of the canal tunnel.
The quarry is about 0.6 hectares (1.5 acres) in area and is privately owned. Access is possible for small items of plant, via a public footpath on the north side. The quarry is large enough to contain the chalk excavated from the new bat tunnel. The approximate volume of the quarry is 40,000 cubic metres (52,300 cubic yds), and the approximate volume of excavated chalk would be 2,500 cubic metres (3,300 cubic yds).
Construction of the new tunnel would involve the excavation of a 4m (13 ft) deep pit. The new tunnel would be approximately 1.5m (5 ft) wide by 2.5m (8 ft) high. Short side tunnels could be excavated, lined with brick and built with lime mortar, leaving crevices for the bats. A waterproof membrane could be incorporated to keep the brick face dry. Another tunnel leading from the pit to join the canal tunnel would provide water to the bat tunnel and so reproduce the existing climatic conditions and protective environment which attract bats to the Greywell Tunnel.
Artificial bat tunnels are not unknown — one at Birchington, near Margate, was constructed in 1986, and a more recent one was built in 1988, in the Itchen valley at Eastleigh.
Whilst the costs of the bat tunnel should be met by the NCC, voluntary labour might be provided by the Society, and further assistance may be forthcoming from wildlife conservationists.
The commencement of restoration work will be subject to the agreement of Hampshire County Council. It is anticipated that HCC will wish to co-operate with a scheme for repair and restoration of the tunnel, particularly in view of its importance for water supply.
Major work cannot start until restoration of the length from Greywell to New Haw is complete in 1990. Preliminary work such as a survey and clearance of excess trees can be started earlier since this will not require any significant finance.
Work on the first and least expensive stage of restoration — the length from Penney Bridge to Eastrop Bridge — could start immediately after formal permission is granted. As far as the second and third stages are concerned, work could start on completion of the first stage, although it is not anticipated that all the finance needed for the later stages of the project will be available by that time.
Some of the work in Greywell Tunnel will be carried out by contractors. In the early stages of the programme, volunteers could undertake drainage work on Greywell Hill. Work on building gabion walls in the approach cutting could also be commenced in the initial phase of the project.
Provided that sufficient funding could be secured, we believe that the whole project could be completed within seven years.
Accurate cost estimates can only be made when detailed plans and specifications are available.
However, even at this early slage, budgetary costs can be projected. For the purposes of this study, costs have been calculated on the assumption that maximum use will be made of the voluntary labour organised by the Society and its associates.
The Society is conscious of the present tight controls on public sector expenditure. Therefore, in making [he present proposals, the Society accepts that a significant contribution will be expected from volunteers. This commitment should not be onerous to fulfil since the current restoration programme will have been completed before work starts on the tunnel and the western end. The Society anticipates that most of its volunteers would be available for work on the project from mid-1990.
The following summary costs are based on a detailed engineering survey and restoration feasibilily sludy made by qualified civil engineers:
* Penney Bridge to Easlrop Bridge — clearance of channel by removal of trees and undergrowth, reinstating towpath and medium depth dredging. Reinstatement of cutting flanks and bank protection.
* Eastrop Bridge to tunnel portal — clearance of channel, removal of trees and building gabion retaining walls.
* Greywell Tunnel — rebuild portal, excavate from above into subsidence pits, clear bore of spoil, reconstruct brickwork at places of collapse, and refill pits with approved fill material (including construction of one ventilation shaft if required).
The estimates include appropriate contingencies. Thus the total estimated cost to return the whole section to navigation is in the order of £1-1/4 million.
One of the five ponds over the tunnel
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The Surrey and Hampshire Canal Society Ltd
Limited Company Status 1977 Registered as a Charity No. 273085
Honorary Secretary Philip Riley BSc (Econ)
Honorary Legal Adviser
SUBSIDIARY COMPANIES (wholly owned by SHCS)
Surrey and Hampshire Canal Cruises Ltd.
Registered in England No. 1296593.
The Surrey and Hampshire Canal Society
As a result of the Society's campaign the canal was taken into public ownership in the early 1970's by the county councils of Hampshire and Surrey. The purchase was made on the understanding that the Surrey and Hampshire Canal Society would contribute towards restoration with an input of voluntary labour and finance. Voluntary labour by the Society has amounted to approximately 28,000 hours per annum, and finance that exceeds expenditure of £40,000 per annum. Total financial input to the restoration to date exceeds £600,000, allowing for inflation.
Since 1973, when restoration work started, the Society has built up a skilled volunteer labour force which has many achievements to its credit. Examples can be seen in the reconstruction of Broad Oak Bridge in Hampshire, the rebuilding of locks on the Deepcut flight hi Surrey, a ten year dredging programme in Hampshire, and puddling Ash Embankment by moving and laying 9,000 tons of clay. The Society is supported in this work by volunteer members of canal associations and societies throughout the UK. When occasion demands, plant and machinery can be obtained on loan from these sources.
A further contribution comes from the team of skilled labour employed by the Society. The four-man team is employed full-time and the Society funds the costs entirely from its own resources. The team gained considerable experience working with persons employed under various job training schemes promoted by the Manpower Services Commission and similar authorities. Since 1977 the Society has received approximately £750,000 from the MSC to finance work experience and training programmes.
In addition to construction work, the Society also operates the John Pinkerton trip boat in both Hampshire and Surrey. Available for party charter or public trips, the service has raised more than £100,000 over ten years. Since it is manned entirely by volunteers, the cost of operation is minimal.
From the above it will be seen that the Society has developed into a flourishing organisation, with a membership exceeding 2,000 people dedicated to complete restoration. It is this record of achievement that gives its members confidence in the practicality of the proposals made in this study.
Recommended Additional Reading
London's Lost Route To Basingstoke P.A.L. Vine
Basingstoke Canal — The Case For Restoration Dieter Jebens
History Of The Basingstoke Canal Glenys Crocker
A Guide To The Basingstoke Canal Roger Cansdale & Dieter Jebens SHCS 1984
The Basingstoke Canal — Western Section
The Basingstoke Canal — A Part of Hampshire's Heritage
Basingstoke Canal Restoration Dieter Jebens & David Robinson
Waterways Environment Handbook
Focus On Bats
Survey of the Flora of the Basingstoke Canal 1986/87
Greywell Tunnel to Mapledurwell Restoration —
An Engineering Proposal
Length presently being restored - 51.5km (32 miles)
Surrey County Council — New Haw to Ash Embankment
THE SURREY & HAMPSHIRE CANAL SOCIETY
Membership of Surrey & Hampshire Canal Society Ltd. - exceeds 2,000
NOW SEE THE FILM
[NB: The above VHS was available only in the 1990s.....]
Last updated May 2006