Southampton and Salisbury Canal: A Portrait
Salisbury Arm: The Summit - West Grimstead to Shootend (Shute End)
Distance: 2.9 miles (4.6 km)
The Summit Level
Lock 14 seems to have been about 220 yards (200 metres) north west of West Grimstead Wharf Approximate position NG Ref: SU205271. WGS84: 51° 02′ 34″ N, 1° 42′ 27″ W. although this is unconfirmed. In all probability, this lock marked the eastern end of the summit or highest level of the canal. It is marked on the 1807 Ordnance Survey map below by a symbol rather like a bridge.
Construction work on the canal seems to have stopped by mid-1804. Whilst boats traded on the canal from near the west end of Southampton Tunnel to West Grimstead until about 1808, work on the summit level was not completed: exactly at what stage construction ceased is not known. Indeed, even the location of the start of the descent to Salisbury at the north-western end of the summit is not confirmed.
This page examines some of the evidence to try to determine some of what was and wasn’t built.
A large number of maps dating from 1807 to the present day have been examined including large scale Ordnance Survey (OS) maps dating from the 1870s. The Maps page provides details of some of these. Written sources have also been checked, notably the booklet ‘The Bankrupt Canal’ by Edwin Welch and the 1962 paper by Hugh Braun. The More information page give details of some of the sources. These have been backed up by examination of parts of the canal on the ground.
One further source of information that was not available to earlier explorers of the canal is LIDAR data which is now publicly available for free on the internet from the Environment Agency. LIDAR uses a laser to scan and map the landscape from an aircraft and is widely considered to be the best method for collecting very dense and accurate elevation data across the landscape. The More information page provides further details on this method of survey and gives links to much background material.
Using these sources, it seems likely that the summit level would have been about 58 metres (190 feet) AODN. The banks of the canal just above the site of Lock 14 seem to be at this level. An OS spot height in the track east of Rectory Farm NG Ref: SU190262. WGS84: 51° 02′ 08″ N, 1° 43′ 45″ W." very close to where the canal would have crossed it is given as 192 feet (58.5 metres). Much of the towpath bank between Tunnel Hill and Silver Street in Alderbury In the area around NG Ref: SU180270. WGS84: 51° 02′ 32″ N, 1° 44′ 38″ W. is in the region of 58 metres. It was intended that the top of the western bank (or dam) of the lake at Alderbury House would be the towpath NG Ref: SU180267. WGS84: 51° 02′ 22″ N, 1° 44′ 37″ W. and this is also mostly just above 58 metres AODN. From LIDAR data, the water level in the lake was 57.8m (189.6 feet) in 2019. Whilst some work seems have been done along much, if not the whole, of the summit level and beyond, that is not to say that there was a completed canal. It must also be remembered that it is now over 200 years since construction ceased: the banks and channel are likely to have suffered erosion or silting up. Plus there will have been changes caused by man since 1804.
West Grimstead Reservoir
Although two reservoirs were planned for the canal, only one was actually constructed. This lay just north of the village of West Grimstead and also to the north of the canal NG Ref: SU205274. WGS84: 51° 02′ 44″ N, 1° 42′ 32″ W.. Near the south west end of the dam, there was a cottage NG Ref: SU204272. WGS84: 51° 02′ 39″ N, 1° 42′ 34″ W. for the the reservoir keeper called ‘The Reservoir’ on some old OS maps but is today called ‘Birdhurst’. Today the site of the reservoir is occupied by a number of fishing lakes at Walden Estate Fishery.
The reservoir was shown on the Ordnance Survey One Inch map surveyed in 1807 when the canal was still in occasional use as far as West Grimstead. It would appear that water level in the reservoir was not shown at its full extent which would almost certainly have stretched north as far as the road at Popes Bottom Farm.
A remnant of the reservoir is also shown on the tithe map for West Grimstead surveyed 30 years after the OS One Inch. It shows an even smaller water area than the One Inch - it is quite likely that, for reasons of safety or possibly lack of maintenance, it had been partially drained by 1837. It seems that it was fully drained in the 1850s and much of the dam removed. By 1876, the First Edition of the 1:2500 scale OS mapping shows no trace of either the reservoir, its dam or the leat that fed water from the reservoir to the canal above Lock 14. However, LIDAR data shows the remains of either end of the dam NG Ref: SU204272. WGS84: 51° 02′ 39″ N, 1° 42′ 32″ W. and NG Ref: SU206273. WGS84: 51° 02′ 41″ N, 1° 42′ 25″ W.".
From examination of the LIDAR data in combination with OS mapping, it would seem likely that the reservoir’s top water level was about 60 metres (197 feet) AODN. The modern fishing lake which occupies the site of the southern part of the reservoir, Monk’s Lake, has a surface level of about 56.7 metres (186 feet).
There is a further lake to the north of the reservoir site which is still in existence very close to the source of the River Dun NG Ref: SU203285. WGS84: 51° 03′ 22″ N, 1° 42′ 38″ W. with a water level in 2019 of about 63.7 metres (209 feet). It is often said that this was a reservoir for the canal. However, it is believed that this was constructed as a water feature within Clarendon Park. Built for Peter Bathurst, MP for Salisbury, Clarendon House was completed in 1737 and is Grade 1 listed. Whether it was agreed that water from this lake could be used to supplement the canal supply is unknown.
The canal reservoir was connected to the canal above Lock 14 by a leat about 200 yards (180m) long. This would have needed a slight gradient to ensure that water would flow to the canal when the controlling sluices at the dam were drawn. From map measurements, the usable volume of the reservoir between the 58 and 60 metre contours would have been in the region of 99,000 cubic metres. Assuming that the size of a lock on the canal was 65ft long, 8.5ft wide with a rise of 8.5ft (19.8m x 2.6m x 2.6m), the volume of water needed to fill that lock would have been approximately 4,700 cubic feet (29,275 gallons or 133 cubic metres). This means that, in theory, the reservoir could supply around 745 lockfuls of water, ignoring replenishment by rainfall. A boat ascending to the summit and descending at the other end would draw two lockfuls of water from the summit. In a dry summer, the reservoir would probably have been inadequate to cope with much traffic on a completed canal.
Hugh Braun in his 1962 paper suggests there was a lock 15 above lock 14 at the east end of the summit. He felt that the summit level was “at about the 200-foot contour”. (In 1962, accurate height information was not readily available.) This seems unlikely as the top level of the reservoir appears to have been no more than about 2 metres (6.5 ft) higher than the canal above lock 14. If the canal had risen through another lock, the summit would have been about the same height as or even higher than the top level of the reservoir which would then have been of no use at all.
Lock 14 to Alderbury Bypass
Above Lock 14 the canal swings to a south westerly course, to reach the Romsey to Salisbury railway some 300 yards (275m) further on NG Ref: SU202270. WGS84: 51° 02′ 32″ N, 1° 42′ 46″ W.. The canal / stream was diverted when the railway was constructed but rejoins the line of the canal after about 70 yards (65m). The canal is now entering the beginning of the summit cutting which was intended to extend for about three quarters of a mile (1.4km) from this railway crossing.
The next feature of note is the access road to the yard of a fencing contractor which crosses the waterway NG Ref: SU201269. WGS84: 51° 02′ 30″ N, 1° 42′ 52″ W.. On the west side of the road (which marks the eastern boundary of Alderbury parish), the cutting is about 2-3 metres deep and spoil from digging it was piled on either side. Over the next 500 yards (450m) the distance between the cutting sides is in the region of 20 yards (18m) widening slightly as one travels west and the cutting sides and spoil heaps grow higher. The cutting is almost impassible as it is thickly wooded, quite marshy and has a stream running eastwards along it. This stream drains a substantial area to the north of Alderbury.
The first edition of the 1:2500 OS map surveyed in 1879 shows the whole cutting floor from the parish boundary to the site of the present bypass to be covered in water (probably quite shallow) but also to be marshy with bushes growing within it. The 1899-1900 revision of the map removed the water covering but retained the marsh and bush symbols and subsequent revisions have maintained this portrayal. The stream draining the north side of Alderbury enters the cutting a few yards east of the railway / bypass crossing Approximate position NG Ref: SU196270. WGS84: 51° 02′ 34″ N, 1° 43′ 16″ W.. Modifications to the junction of stream and cutting seem to have occured as part of building the bypass.
The Salisbury & Dorset Junction Railway was opened in December 1866 from Alderbury Junction on the Eastleigh to Salisbury line about a quarter of a mile (400m) north west of the canal. This line connected Salisbury with Wimborne and the Dorset coast. The railway crossed the canal cutting by means of an embankment which incorporated a culvert connecting the two severed portions of the cutting. This crossing was at the point where the canal started to swing through 90 degrees from running in a westerly direction to a more southerly course NG Ref: SU196270. WGS84: 51° 02′ 34″ N, 1° 43′ 18″ W.. The railway was closed in May 1964 as recommended in Dr Beeching’s report of 1963.
The A36 Alderbury Bypass dual carriageway was opened in 1978 and crosses the line of the canal at the same location as the earlier railway but at a slightly different angle and with a wider footprint. Today, with no pedestrian crossing, the road forms a barrier between this section of canal and the next.
It is believed that a wharf was constructed in this area, probably at the junction of the stream with the canal Approximate position NG Ref: SU196270. WGS84: 51° 02′ 34″ N, 1° 43′ 16″ W., for use until the next length of canal was completed . Hugh Braun in 1962 mentions Georgian brickwork in this area - whether this still remains after construction of the bypass and after recent remedial work on the road’s embankment and drainage in the area is unknown.
Alderbury Bypass to Whaddon
South of the present bypass, the canal would have entered the deepest part of a large cutting which was to extend to the south side of the Southampton to Salisbury turnpike road. However, the cutting was not completed when construction ceased and the proposed 100 yard (90m) long tunnel under the road was not even started.
During construction of the cutting, spoil was tipped beside it making the cutting appear deeper and even more impressive. Horses were almost certainly used to haul the spoil out of the diggings but that spoil had first to loosened by hand using pick, mattock and shovel. The volume of material moved is prodigious.
It appears that the cutting was first flooded when an embankment for the Salisbury and Dorset Junction railway was constructed across the cutting NG Ref: SU196270. WGS84: 51° 02′ 34″ N, 1° 43′ 18″ W.. This line opened in 1866 (and closed in 1964). From maps, it seems that the water level was lower than today.
The current water level is nearly 20 feet (5.9m) higher than planned summit level hence the "lake" is much wider than a normal canal. The water is impounded at its current level by spoil tipped in the northern part of the cutting during construction of the Alderbury bypass which opened in 1978. Although the road is considerably wider, this crosses the cutting in the same place as the former railway.
In November 1802, it was proposed that a temporary wooden railway be built (see details) to join the end of the navigable canal to the turnpike road. George Jones made a quote for its construction giving the length of it as 629 yards (575m). After canal construction stopped in 1804, it was reported that Jones had sold the wooden rails towards the salary he was owed. Previous investigators of the remains of the canal have made various proposals for the exact location of this railway but all seem to have foundered on the length of the line.
However, no-one seems to have considered that it might parallel the line of the canal. Using Google Earth, measurements along the west side of the cutting from the Southampton Road have been taken. Such a railway would reach the side of the canal at the site of the wharf Approximate position NG Ref: SU196270. WGS84: 51° 02′ 34″ N, 1° 43′ 16″ W. that is thought to have been built immediately east of where the later railway was to be built across the canal. The distance from the road is in the region of 630 yards (576m).
This line would have followed the east side of the present day Firs Road from the main road until it reaches the present day Alderbury Primary School Approximate position NG Ref: SU193269. WGS84: 51° 02′ 31″ N, 1° 43′ 31″ W.. The line continues northward today as a footpath until it reaches the bypass which prevents further progress NG Ref: SU195271. WGS84: 51° 02′ 36″ N, 1° 43′ 22″ W.. This line falls at a fairly consistent gradient and to the present author the northern section looks very much like a former narrow gauge tramway.
Whaddon to Alderbury Park
Originally the settlements of Whaddon and Alderbury were separate and distinct but, with 20th century development, they have coalesed and the whole entity is referred to by the latter name.
Although the contract to dig the tunnel under Southampton Road was let in 1798, it was never dug. From measurement of the distance between the dug cuttings on either side of the road on the 1:2500 Ordnance Survey map surveyed in 1876-9, it would appear that the tunnel was intended to be about 60 or 70 yards (55 to 65 metres) long although the original proposals were for a 100 yard (91m) long structure. It appears from this map that there was originally a cutting on the south side of the road and that it contained water albeit marshy. But for the first 100 yards (91m) or so this cutting is today filled in and has houses and gardens built over it. Southwards, the overgrown marshy remains of the canal extend as far as the track at Toadland, east of Rectory Farm.
South of this track, about 120 yards (110m) of the canal has been eliminated but then the line of trees marks out the canal as it swings through 90° to run in a north-westerly direction south of Rectory Farm. Shortly a small valley is encountered and the remains of an embankment and culvert can be seen crossing it. This little valley was to have been dammed to form a reservoir for the canal but it was not built. About 150 yards beyond the stream in the little valley, the visible line of the canal comes to an end. From here until the lake at Alderbury House, the canal has been ploughed out or infilled. That construction was at least started on this stretch of the canal is confirmed by tithe maps covering Alderbury that show the alignment.
Alderbury House, listed Grade II*, was built by George Yalden Fort, a Salisbury hatter, in 1790 having acquired the stones of the recently dismantled cathedral campanile. Fort became one of the two joint treasurers of the canal company. The canal was to cross the grounds just south of Alderbury House. To "prettify" the canal a lake was formed where it crossed a small valley. The embankment enclosing the lake was in fact to be the towing path. The lake is still in existence.
To the north of the lake, the canal had to cross a small spur of land which was tunnelled through. This fact is remembered in the name of the lane that crosses the site of the north end of the tunnel and passes Alderbury Church. Details of how the tunnel was to be constructed was laid down in the 1795 Act of Parliament authorising the canal. The tunnel was built by cut and cover and the spoil tips were hidden with a shrubbery and trees planted over them. It is reported that the tunnel was filled in under the road by the County Council in about 1937 and that depressions in the ground above the rest of the tunnel mark where the vaulting has collapsed.
Alderbury House to Shootend (or Shute End)
The course of the canal can be traced winding its way across a valley north of the site of the tunnel and west of and below Alderbury Church. The last visible remains of the course of the canal is where it was to cross the track called Silver Street. On the north-west side of Silver Street, a small stream that runs beside the track in a strip of woodland seems to enter the canal alignment for about 60 yards (55m).
Beyond this woodland, there is no visible trace of the canal on the ground until the course of the intended canal enters Shootend Copse where the line of the canal can be found again. Indeed no indication of the course of the canal appears on the tithe map for Alderbury or on later Ordnance Survey mapping.
However, from mapping derived from LIDAR data, parts of the alignment can be traced. It also seems that the canal would have descended one lock from the summit level before reaching the wood. It is not possible to positively identify whether that lock was north west of Silver Street or much nearer Shootend Copse. However, close examination of the LIDAR data seems to indicate a slight depression of the right dimensions for an infilled lock NG Ref: SU177274. WGS84: 51° 02′ 47″ N, 1° 44′ 54″ W. immediately to the south of the drive to Alward House from Shute End Road. Also the level of the course of the canal either side of the drive appears to differ by about 7 or 8 feet. This position would have made the summit level longer than if the lock were built at Silver Street and thus would increase the volume of water the summit could hold. For a map of the area based on LIDAR data see the next page Shootend - Salisbury.