Restoration Plan: Lapal East; Phase-1

 

EP 1 : The Selly Oak Section [LESO] :

This 911 yards long section (833m) joins the W&B canal at Selly Oak Junction and includes the three sub-sections of Battery Park, Harborne Wharf and Selly Oak Park.
It has been identified as the Phase-1 project, with the recommendation that pre-restoration preparatory work should commence in the Harborne Wharf length, as a demonstration of restoration intentions and methods.

EP 1.1 Battery Park [LE1] :

The centre of the former Selly Oak Junction is almost exactly beneath the overhead power lines as they cross the W&B towpath which is also slightly raised in this vicinity. 
From this Junction to Harborne Lane, the Battery Park trading estate (formerly the site of the Birmingham Battery and Metal Company) flanks the LE1 section of the Lapal Canal and its restoration will be timely. Sainsbury's in conjunction with BCC have very elaborate Plans to improve this area of Selly Oak and include the provision of a new by-pass road to relieve serious traffic congestion. The first steps in the execution of this development are due in 2004.

EP 1.1.1 General - LE1

This first canal section comprised two small basins linked by a narrows, and a third side-arm basin. All are infilled so it is likely that the channel bed and sides have been preserved intact. The infill is approximately 2.5m to 3m above water level alongside the W&B, but gradually reduces to 'normal' towpath level at the entrance to the old nearside, side arm basin where walling and a cable duct remain. The infill gradually rises again to a depth of approximately 2m at the Harborne Lane Bridge [LE1B]. Some of this infill and surrounding land has toxic contamination, so this section is presently fenced-off with no route through for W&B cyclists and ramblers. (Also see EP1.4.2 .)

EP 1.1.2 The W&B Towpath

The original junction with the W&B was a traditional, narrow opening, crossed by a long-removed footbridge. A replacement roving Bridge [LE0] will be required to provide continuity to the W&B towpath. There is also a need for interim, occasional access to the MEB sub-station for heavy plant. (A minimum width of 4.5 metres and wheel-loading of 12.5 tonnes, may be required.) It is provisionally proposed that a swing bridge of Bailey-type construction might suffice, although it is preferable for this sub-station access to be through the nearside development so that a permanent roving footbridge may be provided for the W&B, built to a traditional design (perhaps like the new bridge - 84A - on the W&B).

In the vicinity of the former junction, the W&B towpath and the MEB access lane are both elevated above normal towpath level. Landscaping will be required to match the W&B and Lapal towpaths; preferably by lowering the elevated W&B towpath sections for all to be at normal level.

EP 1.1.3 The W&B Junction- LE0

In landscaping the junction towpath levels, consideration should also be given to the junction itself, noting that a former offside, side-arm to the W&B has been filled-in and is now part of a Builders' premises. To simplify vessel turning manoeuvres at the junction, the first (eastern) basin might have a wider than normal mouth onto the W&B and become an open-sided 'square', or have a funnel-shape (in plan) as a compromise. The necessary water management control would then occur at the narrows [LE1N], approximately 50 yds away. If so, perhaps the bridge could be constructed over this narrows, with the W&B towpath taking a small loop diversion around the east basin, as it now does at the recently installed Winding hole by bridge 84A.

(It seems likely that this narrows was not in place when the original canal was constructed, being provided later as part of the Brewin's "Accelerator" water control. Thus, the narrow junction would have been required as the traditional means to isolate the two canals in the event of water-loss. If the nearby narrows is reinstated, as suggested, it would now meet the water-management needs instead of a narrow-mouth junction.)

EP 1.1.4 Harborne Lane Basin and Bridge

The second (western) Battery-Park Basin [LE1.5] need not be restored to its former basin profile. Instead, the canal might proceed at standard width (e.g. 32ft, 9.7m (water); 37ft, 12m (corridor)) from the narrows to the Harborne Lane Bridge, thereby releasing a small width of land for developers to incorporate into their landscaping.

The Harborne Lane Bridge [LE1B] appears to be sound and would benefit from sand-blasting to remove graffiti and reveal its former splendour. It is also noted that the bridge-hole is presently sealed at both ends to prevent unsavoury activities occurring in the former cave-like hide-away. Even before restoration proper, it would be expedient to remove the sealing infill and open the bridge hole, perhaps as part of an interim footpath-come-cycleway provision to link the Castle Walkway for W&B towpath users.

EP 1.2 Harborne Wharf [LE2] :

The short (118 yds) length of basin canal between Harborne Bridge and the Selly Oak Park Bridge [LE2B] that included the Harborne Wharf basin was partly infilled and landscaped as a picnic area (in the 70's) but had since become substantially overgrown with trees and shrubbery. The infill is almost complete in the eastern 'half' [LE2E] but reduces, in the western 'half' [LE2W], where shallow water lies as an indication that the puddling is likely to be sound. PHOTO. The embankment on the southern (offside) flank, rises quite steeply to the hillock along the western half and the fence is in need of considerable repair.

The Castle Walkway is on the north side as it uses the former towpath from an access by Harborne Lane Bridge [LE1B], and is then on the south side immediately beyond Park Lodge Bridge; known to be the oldest masonry accommodation bridge in the BCN (though not a Listed Structure). This bridge is in need of sympathetic repair (e.g. pointing, with traditional lime mortar) and the restoration of its former parapet walls.

EP 1.2.1 Tasks in LE2

At present, the channel under the masonry bridge is fully infilled to protect a drainage provision and allow pedestrians to cross into Selly Oak Park from the Harborne Wharf. However, the former towpath exists along the north-side of the bridge hole and is an integral part of the structural foundations.
As part of the restoration, it will be prudent to retain this towpath section and provide a simple bridge-access 'loop' on the north-west corner of the bridge, perhaps as a spiral of timber-retained steps. This would establish the necessary conversion into a Roving bridge that provides crossing access to the south-side towpath, as proposed for the main parkland length (and beyond). A south-side access into the main parkland already exists and, with this additional feature, the entire arrangement could achieve full Turn-Over authenticity for this delightful bridge. Later, the "wheels access" requirement could be conveniently achieved by way of a gradual-incline pathway leading directly from the towpath up to the north-east corner of this bridge.

Consideration must also be given to the potential danger posed by the offside embankment; children falling down (or launching supermarket trolleys, etc.) into the canal. Some imaginative landscaping could eliminate this problem, particularly if the canal was rebuilt to a standard width (typically about 32ft or 10 metres), rather than its former basin profile. If so, the steeper and eroded sections of its incline could be made more gradual by re-deploying infill earth as backfill, perhaps with a turf dressing and Spring-flowering bulbs beneath. This would occur between and around all of the mature trees which will remain in situ, well behind the new offside profile, to retain the leafy canopy over the canal to preserve and enhance all of the pleasant dingle properties, for boaters and walkers alike approaching Selly Oak Park.
It will provide a "dramatic" contrast to the Battery Park section when the latter is re-developed with water-side properties.

EP 1.2.2 Actions in LE2

The Harborne Wharf section has now been the site of the first pre-restoration clearance work in the East; (November 14, 15, 1998). This work necessarily removed some semi-mature trees (that had been planted when the area was first landscaped as a picnic area). It is proposed that replacement saplings be planted soon in the general vicinity (some within Selly Oak Park) but in consultation with local residents and co-ordination groups such as the Friends of Selly Oak Park.

EP 1.3 Selly Oak Park [LE3] :

For most of its length (385 yds), the Selly Oak Park channel has no infill and is easily recognised as derelict canal. The channel and sides are quite heavily overgrown with shrubbery and trees, and there are some drainage provisions built into the bed. Conversely, in other places, most notably near Park Lodge Bridge, it still retains (shallow) water. PHOTO
Thus, there appear to be few obstacles to restoration, except for the construction of towpath and moorings.

The original offside adjoins the open parkland of Selly Oak Park and two lines of very mature trees flank the present footpath. The trees along the cusp will present a problem if this is to become the towpath side with a mooring which is to be straight and regular. Consideration should also be given to the type of canal restoration here. In general, moorings require a vertical side with brick capping or a flat bottomed 'V' section constructed from puddle with geotextile as wash protection. A vertical side would certainly be required for the 'disabled' moorings, even if the remainder was left with a gradual incline, as a satisfactory profile for moorings that are designated short-stay only.

The adjoining Reservoir Road properties will all benefit from "moat security" as will the Park Lodge Nursing Home just to the west of Park Lodge Bridge. If its proprietors were to re-shape the garden slightly, their residential clients may sit out in safety, to contemplate the canal and its vessels ("gongoozle"), with a good sight-line to the moorings and boats tied alongside.

EP 1.3.1 Tasks - Canal

The first task along the Selly Oak Park sector, should be tree and shrubbery survey and management; commencing as soon as possible, but with the long-term aim of achieving a wooded ambience similar to that of Harborne Wharf. This task requires rights of access to conduct preventative maintenance. If the original north-side towpath is not to be re-instated, saplings may be planted as 'replacements' for the mature trees, with the involvement and agreement of the householders.

At the North-West corner of Selly Oak Park, a terminal winding [LE3W] should be provided on the basis of an interim 'cut' into the parkland at that point. The provisional suggestion is to install this where the present infilling begins; approximately 35 yds east of the boundary corner. (The design could be a "carbon copy" of the winding hole recently provided on the W&B at the Vale in Edgbaston.) Thus, the present infilling might remain, perhaps with improved landscaping, and tree and shrubbery management, to preserve and enhance the pedestrian access to the Castle Walkway as it proceeds westwards (along the infilled canal line). When the Phase-2 sections are opened, this winding might be replaced with a narrows, either at the true park boundary [LE3B] or where an original narrows appears to have existed (near the MEB sub-station, in LE4.1), but is presently obscured by infill. Conversely, this winding might be retained as a permanent feature. If so, the canal might be restored up to and including the narrows, which would be stanked-off for the time being as the limit of Phase-1 water.
However, if sheet-piling (or similar, see EP1.5) has become the acceptable method of re-profiling the channel, it is conceivable that the Selly Oak Park length may be restored in two 'halves', to reduce the environmental impact of the disturbance. The first 'half' would be the eastern length as an extension to the Harborne Wharf section. Then, a full year or more of recovery time might elapse before the western 'half' is worked. If labour and financial constraints are even tighter, this restoration could be undertaken as three separate but sequential 'thirds'. (A one-third length is approximately 120 yds and is thereby almost exactly the same restoration length as the full Harborne Wharf section.)

EP 1.3.2 Tasks - Parkland (safety and security)

It will be prudent to provide safety-rail fencing along the entire length of the park-side canal to protect the young when playing in the Park. This fencing should continue as protection for the offside embankment in Harborne Wharf. The inclusion of near-ground-level lighting at intervals along this railing would add to the night-time ambience and security of the amenity.

EP 1.4 Alternative Restoration Strategies

The need for some high-profile Public Relations (PR) is of paramount importance if the entire Eastern Approach Restoration Project is to proceed successfully. In principle, there are two options;

  1. restore the three sub-sections in incremental order away from W&B, or
  2. restore the three sub-sections in reverse or semi-reverse order.

The strength of the first option is that navigable canal is achieved from the outset and, significantly, this would initiate the process by which the entire Lapal Canal begins to re-appear in national waterway guides, maps, booklets and journals. Indeed, it might have been significant PR if the first Battery Park (eastern) basin could have been in water again by 1998; the bi-centenary of the canal's first opening in 1798. This basin is currently in undeveloped land, well away from any of the residences that adjoin the subsequent sections, but close enough for those residents to visit and inspect.
Conversely, the weakness of this first option lies in the high costs and complexity of the tasks that are needed to restore what is only a relatively short length of canal.

The alternative option allows the Selly Oak Park length to be restored first as a "linear drainage channel". The major weakness is that it still does not achieve a navigable example of the Trust's restoration intentions, but has the following set of mitigating strengths.

EP 1.4.1 A Local Amenity

Of the three Phase-1 sub-sections, the two Selly Oak Park lengths [LE2 & LE3] offer the greatest impact for the surrounding community by becoming an attractive water feature and amenity for this parkland, as noted in the Outline Plan. In several ways, it is also the section that requires the least amount of engineering work having almost no infill to remove before restoration proper begins. In these respects, it is similar to the now-restored section along The Leasowes (recreational parkland) in Halesowen.

If so, the Battery Park section with its more complex engineering, legal and organisational issues could be left until the significant level of funding can be acquired for this work. As the LCT applies for such funds from potential sponsors and benefactors, the restored Selly Oak Park sections would also act as a demonstration length to strengthen the case. The now-cleared Harborne Wharf section has already begun to stimulate increased awareness and reaction.

Until all three sections are connected to the W&B, the water-level can be held much lower than navigation level but still sufficient for the aquatic wildlife to become re-established. If so, the cost of safety fencing might be deferred.

EP 1.4.2 The Rambler and Cyclist

If this alternative strategy is implemented, the LCT-EAPG recommends that it should be accompanied by work to create an interim footpath-come-cycleway along the towpath line of the Battery Park canal section. At present, W&B towpath users have no direct route to the Castle Walkway, being required to make a detour around the Battery Park trading estate on roadside footpaths, instead. The provision of a route, along a nearside line (north side of the infill) and through the Harborne Lane bridge hole into Harborne Wharf, would establish this 'missing link' and make a further contribution to the profile-raising and amenity value of this first restoration phase. Such a provision would also accord with the objectives given in the joint BCC/BW Lapworth (Cycle) Loop initiative.

It is conceivable that the construction of this footpath-come-cycleway could become attached to an appropriate Youth Training initiative (e.g. one of those highlighted in the Central Government's July '97 Budget).

EP 1.4.3 A Mock-Up Section

It is also strongly recommended (by the EAPG and the LCT's main Planning sub-Committee, 97/07/30) that a short length of no more than about 10 yds, should be prepared along Selly Oak Park as an interim demonstration of the proposed restoration methods. The chosen section would be cleared of all trees and shrubbery, and have walling (or piling) and brick capping, together with levelling and landscaping of its offside and towpath flanks. It would not be re-watered, but left as a dry and fully visible "mock-up" as a further contribution to the "PR" campaign. For this purpose, it would also be accompanied by a substantially-constructed notice of explanation and, perhaps, a park bench.
A suitable length has been identified, about 100yds west of the masonry bridge (just beyond the gradual bend).
Provisional costs between £350 and £500 have been estimated for this, and construction details are being prepared.

EP 1.5 Alternative Restoration Methods

In sections where the existing bed and channel sides have deteriorated beyond simple repair, additional restoration detail will be required. Four methods are under consideration;

Concrete Walling

Sheet Piling (backfilled with puddle and infill)

Sheet Piling (backfilled with concrete)

Gabion or "Mesh Retention" - offsides only

Although Concrete Walling has been used at The Leasowes (with the very special requirements of its uniquely steep embankment sides), Steel Sheet Piling is favoured for sections of the Selly Oak Extension Canal where strong reinforcement is required. It has the advantage of being easily contoured to retain the gradual curves of the former profile and will tolerate variations in channel depth. It is held in place by ground anchors at regular intervals (e.g. every 10ft or so). This requires occasional sheets to be set back a few feet behind the Piling itself with perpendicular tie bars underneath the top layer of backfill. A backfill of earth and puddle clay may be used where the adjoining land is at, or above water-level, whereas a concrete backfill is used where the adjoining land slopes down below the canal. It is a method that is widely used on existing waterways (BCN and elsewhere in the UK) and lends itself to sponsorship ploys; e.g. engraving, as a permanent record of a donor's contribution.

On the nearside it may be capped with brickwork to form an aesthetically pleasing towpath and, on an offside flank, it may be backfilled to a level where natural vegetation (or householder garden landscaping) provides the finished appearance. Apart from the topmost 9-18 inches of waling (horizontal tie bar; either steel or timber), the remainder is invisible for being below water. For householders, the abrupt 'step' of the resulting hard edge is also a desirable barrier that prevents amphibious creatures forming habitats in their gardens - an aquatic mini-ha-ha !
(Piling has the disadvantage of being somewhat unsightly during the installation periods of a restoration.)

The "Mesh Retention" ("Mesh Stabilisation", Gabion) method may be considered for offsides where the adjoining land rises above water level; the south side of the Harborne Wharf basin being a good case in point. The eroded land is layered with removed infill and additional earth, to slope down into the cut. At bed-level, the clearance width to the nearside is 20-25 ft, while, at water-level, the width may increase to a nominal 35ft or so, but with a varying profile that adds character to the offside for not having a uniformly straight edge. The portion that is (or will be) below (navigation) water-level is sealed with puddle clay. The heavy-duty mesh binds the puddle and embankment earth, and the latter may be given a turf dressing. This soft-edge method of re-profiling also has the advantage of a quite speedy recovery to a natural appearance, once the work is complete, and is 'friendly' to amphibious creatures, both during the 'linear-lake' phase and again when the water is raised to full navigation level.

 

Strategy Plan Phase-1 Phase-2 Phase-3
    Parkland Backland Meander Heritage Flank
Western Approach Canal :  West West Hawne Basin / Leasowes Park Abbeyfields St Mary's
Eastern Approach Canal :  East East Battery Park / Selly Oak Park Lodge Hill Weoley Castle