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Principal Inspection Report Rochdale Canal Embankment 2 Hollins Mill Lane North West Waterway RD-001-010-L September 2006 ESPI/0607/7600/RD-001-010-L Carl Conwell Assistant Waterway Asset Surveyor Geotechnical and Earth Structure Team Fearns Wharf Leeds

SAP Executive Summary

RD-001-010-L Embankment 2 Hollins Mill Lane Dimensions : Length: 540 m Height: 5.5 m max Slope Angle: 31° max Access : Access is via the towpath from Hollins Mill Lane, Embankment 2 is located below the towpath side of the canal with moderately high levels of vegetation. Defects and Monitoring : Inspectors should check known areas of potential leakage reporting any significant changes. Inspectors should also include visual monitoring for any retaining wall or tree deformation occurring on the slope face, paying particular attention for possible settlement along the crest/shoulder, loss of parapet wall and any potential lower slope face/toe wall instability. Any of these indicators should be reported immediately.

PMO

Z2 10466951

Z4’s 10466952, 10466953, 10466954, 10466955, 10466956, 10466957, 10466958.

BRITISH WATERWAYS

EARTH STRUCTURE PRINCIPAL INSPECTION REPORT EXECUTIVE SUMMARY

Structure Record Functional Location Code : RD-001-010-L Structure Name : Embankment 2, Hollins Mill Lane Location : Sowerby Bridge Grid Reference (to centre) : SE 056 238 Waterway Unit : North West Structure Type : 9 Date of Previous Inspection : N/A Inspection Data Date of Inspection : 26 September 2006 Inspector : Carl Conwell Length Inspected : 580 m Structure Length : 540 m Height : 5.5 m Slope Angle : 22° to 31° Freeboard : 450 mm to 700 mm Canal Width : 9 m minimum Pound Length : 4.2 km Weather Conditions : Dry with sunny periods Inspection Outputs Condition Grade : D Serviceability : 1 Consequence of Failure : 4 Known Date of Construction : Synopsis of Main Defects : Leakage/seepage from the slope face and toe. Trees growing from the retaining walls and on

the embankment shoulder. Face and toe retaining walls in bad condition

with displaced, collapsed and bulging areas. Numerous lengths of displaced and vandalised

parapet wall. An area of crest settlement. Summary Of Estimated Costs Short Term (<1 yr) : £77,500 Med. Term (1-5 yrs) : None Long Term (5-10yrs) : None Inspector : Carl Conwell Signature………………………………Date………………

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BRITISH WATERWAYS

EARTH STRUCTURE PRINCIPAL INSPECTION REPORT RECORD SHEET

RD-001-010-L

APPROVAL RECORD Report Status

Revision Prepared By/date

Checked By/date

Authorised By/date

Issue Date

Final

0 CC Apr 07 AFa Apr 07 AF May 07

DATA RECIEPT RECORD Waterway Unit Asset Manager : Signature………………………………Date……………… Operations Manager : Signature………………………………Date………………

ESPI/0607/7600/RD-001-010-L

BRITISH WATERWAYS

EARTH STRUCTURE PRINCIPAL INSPECTION REPORT

CONTENTS

Principal Inspection Report

Summary Functional Location Data

Principal Inspection Photographs

Principal Inspection Plan

Note All chainages given in this report have been referenced from Hollins Mill Lane Footbridge (ch-004) this bridge was not recorded in SAP.

Embankment 2 was assumed to run from ch-000L to ch-054L.

Please refer to the site plans for full details of this inspection.

1.0 Features & Condition 1.1 The Rochdale Canal forms part of the South Pennine Ring which includes the

Huddersfield Narrow and Broad Canals, the Ashton Canal along with the Calder and Hebble Navigation. The ring connects to the Bridgewater Canal at Castlefield. The Rochdale Canal is located to the north of Manchester and trends generally northeast towards Sowerby Bridge where it joins the Calder and Hebble. This canal flows through generally open areas of pasture, along with urban areas north of Manchester. The flow within the canal is northeast to southwest.

1.2 In the area of interest the canal trends in a north westerly direction and is situated on steep sidelong ground. It is bounded directly to the south west by Hollins Mill Lane with a number of works premises and the Puzzle Hall public house. The River Calder runs parallel to the canal beyond all the works premises. To the north east on the off side bank of the canal, the canal is bounded by wooded steep sloping ground and cliffs with residential properties situated above and beyond higher up the valley side.

1.3 The BGS 1:50,000, Sheet 77, Huddersfield, Solid & Drift (1978) edition shows the area of interest to be underlain by fluvio-glacial Gravel associated with River Terrace Deposits from the River Calder. These drift deposits overlie Namurian Millstone Grit Series with Upper Kinderscout Grits of the Upper Carboniferous Period.

Embankment 2 Hollins Mill Lane – Towpath side

Crest 1.4 The crest of the embankment was generally between 2.5 m to 4 m wide. A masonry

parapet/boundary wall was formed from a continuation of a crest shoulder retaining wall. The parapet/boundary wall ran along the back edge of the towpath throughout the embankment as a property boundary and to prevented public access to the slope face. The crest and shoulder were vegetated with a low to moderately high ground cover and low canopy cover. Effective freeboard was typically 0.5 m to 0.7 m along the towpath. A partially worn gravel surfaced towpath was typically 1 m in width along the middle of the

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crest with mown grass verges. The shoulder was generally sharply defined by crest shoulder retaining walls against the slope face. The following points were noted: • ch-000L to ch-003L – A masonry crest shoulder retaining wall formed from a

demolished building, ranged in height between 1.2 m to 1.5 m high and was in a reasonable condition. A 1.1 m high masonry parapet/boundary wall in a reasonable condition was formed from a continuation of the retaining wall.

• ch-003L to ch-004L – A 6 m high embankment retaining wall was comprised of masonry in a reasonable condition over brickwork in a reasonable to poor condition. A 1.2 m high masonry parapet wall in a reasonable condition was formed from a continuation of the retaining wall.

• ch-004L to ch-013L – A masonry crest shoulder retaining wall above a section of earth slope face, ranged in height between 2 m to 3.5 m high and was in a reasonable to poor condition. A 0.6 m to 0.8 m high masonry parapet/boundary wall in a reasonable to poor condition was formed from a continuation of the retaining wall.

• ch-004L to ch-013L – The masonry parapet/boundary wall along this length had a number of vandalised/displaced sections of missing masonry at the following locations: ch-007L a 3 m length; ch-009L a 1.5 m long hole & ch-012L a 2 m long hole.

• ch-013L to ch-023L – A masonry crest shoulder retaining wall above a terraced/benched embankment face, ranged in height between 1.5 m to 2.2 m high and was in a reasonable condition. A 0.4 m to 0.9 m high masonry parapet/boundary wall in a reasonable to bad condition was formed from a continuation of the retaining wall.

• ch-013L to ch-023L – The masonry parapet/boundary wall along this length had a number of vandalised/displaced sections of missing masonry at the following locations: ch-018L a 2 m length; ch-019L a 1.8 m length; ch-021L a 1.2 m length & ch-022L a 2.6 m length.

• ch-017L – A mature tree was growing on the shoulder and the tree roots were causing the shoulder surface to bulge. A number of other smaller trees were located along the shoulder nearby.

• ch-023L to ch-033L – The parapet/boundary wall was completely missing from along the top of this section of masonry crest shoulder retaining wall.

• ch-023L to ch-033L – A masonry crest shoulder retaining wall above a terraced/benched embankment face, ranged in height between 1.5 m to 2.2 m high and was in a reasonable to poor condition with patches of masonry displaced from the upper courses.

• ch-028L – A 12 m long area of slight crest settlement with a fall of 0.1 m was noted adjacent to a poor clay repair along the toe of the waterway wall (which had also settled to a freeboard of 450 mm from 500 mm). The repair had gaps and holes in the clay with visible indicators of leakage.

• ch-032L – A 2.5 m long section of masonry crest shoulder retaining wall was 1.6 m high and in a reasonable to bad condition with patches of upper courses displaced. There was no parapet/boundary wall on top of the retaining wall and the wall was located above a recess with a masonry buttress, that appeared to have formed the sidewall of a former chute.

• ch-033L to ch-052L – A masonry crest shoulder retaining wall above a terraced/benched embankment face and a section of earth slope face, ranged in height between 0.6 m to 1.5 m high and was in a reasonable condition. A 0.4 m to 0.9 m high masonry parapet/boundary wall in a reasonable to bad condition was formed from a continuation of the retaining wall.

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• ch-033L to ch-052L – The masonry parapet/boundary wall along this length had a number of vandalised/displaced sections of missing masonry at the following locations: ch-037L a 1 m length; ch-038L a 0.6 m length & a 1 m length; ch-042L a 2 m length; ch-043L a 10 m length; ch-046L a 11 m length; ch-049L a 4 m length & ch-051L a 3 m length.

• ch-055L to ch-057L – A roadside gap in the boundary wall permits vehicle access onto the embankment crest.

Slope Face 1.5 Apart from some short sections of retaining wall that extended to the full height of the

embankment, the face of the embankment was generally regular in appearance with benched upper and lower tier retaining walls and overgrown terraces. Only at each end of the embankment was there earth slope faces between the shoulder and toe retaining walls. These sections of slope face were generally planar in profile and inclined at between 22° and 31°. The terraces and the areas of slope face were vegetated with a moderate to high density of ground cover and a low to moderately high density of canopy cover. The following points were noted: • ch-001L to ch-003L – The site of a demolished building that had once occupied the

slope face had been transformed into a grassed earth slope between toe and shoulder retaining walls.

• ch-003L to ch-004L – A 6 m high embankment retaining wall adjacent to the access steps of Hollins Mill Lane Footbridge was comprised of masonry in a reasonable condition over brickwork in a reasonable to poor condition. Small damp patches were visible on the lower part of the wall at the location of an old leakage issue. The damp patches were considered to be insignificant and the old leakage cure was considered to be a good repair.

• ch-012L – A mature tree was growing from the bottom of the shoulder retaining wall and leakage was issuing below onto Hollins Mill Lane at the toe. Seepage with an indiscernible flow rate was also issuing from the bottom of the shoulder retaining wall adjacent to the tree. A poor clay repair along the toe of the waterway wall was noted above the tree and it was considered that tree root penetration was the main cause of the leakage. The clay repair had gaps and holes in the clay with visible indicators of leakage.

• ch-013L to ch-032L – The middle section of slope face was benched with a middle tier retaining wall between the shoulder and toe walls and overgrown terraces. The upper terrace was between 2 m to 3 m wide and the lower terrace was between 2.4 m to 3.4 m wide. The middle tier retaining wall was 1.7 m to 2.1 m high and in a reasonable to bad condition with patches of displaced and robbed masonry.

• ch-029L – Masonry access steps located on the benched embankment face between the towpath and Hollins Mill Lane were in a reasonable to bad condition.

• ch-031L – A former air raid shelter built underground into the embankment had its entrances blocked up.

• ch-032L – A masonry buttress that appeared to have formed the sidewall of a former chute, was in a reasonable to bad condition with patches of upper courses displaced. The buttress was located above an area with sidewalls recessed into the toe.

• ch-033L to ch-039L – The slope face was benched with a middle tier retaining wall between the shoulder and toe walls and overgrown terraces. The upper terrace was between 2 m to 3 m wide and the lower terrace was 3.5 m wide. The middle tier retaining wall was 1.8 m high and in a reasonable to bad condition with sections of displaced and robbed masonry. The masonry was robbed to construct waterway walls during 1986 when the canal restoration work reached this location.

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Toe 1.6 The toe of the embankment was generally sharply defined by toe retaining walls against

the pavement of Hollins Mill Lane. The lower terrace above the toe retaining wall was vegetated with a moderately high to high density of ground cover and a moderate to moderately high density of canopy cover. The embankment varied in height between 1 m and 5.5 m (typically 5 m) below canal water level. The following points were noted: • ch-001L to ch-003L – A masonry toe retaining wall was constructed along the toe at

the site of a demolished building and was 2.3 m high and in a reasonable condition.

• ch-004L to ch-013L – A masonry toe retaining wall to an earth slope face section of embankment, ran adjacent to Hollins Mill Lane, it tapered from 1.4 m up to 2 m in height and was in a reasonable to poor condition.

• ch-005L – A bulge in the 2 m high toe retaining wall protruded over the footpath pavement to Hollins Mill Lane. The bulged area of the wall was 3 m long with a 0.25 m bulge out of structural alignment.

• ch-012L – A mature tree was growing from the bottom of the shoulder retaining wall and leakage was issuing below onto Hollins Mill Lane at the toe. Leakage ran from the bottom of the toe retaining wall along a 2.5 m length of the wall with an estimated total flow rate of 0.3 l/s. The leakage ran across the lane to a road gulley beside the Puzzle Hall public house. Seepage with an indiscernible flow rate was also issuing from the bottom of the shoulder retaining wall adjacent to the tree. A poor clay repair along the toe of the waterway wall was noted above the tree and it was considered that tree root penetration was the main cause of the leakage, in conjunction with slope face settlement that resulted from modifications to the toe retaining wall (see ch-012L below). The clay repair had gaps and holes in the clay with visible indicators of leakage. After the canal was re-opened to navigation during the mid to late 1990’s, the local authority canal restoration team based at Callis Mill in Hebden Bridge, had a number of attempts at curing this particular leak (which was worse in appearance) due to complaints from the then landlord of the public house.

• ch-012L – Two attached areas recessed into the toe had masonry sidewalls that were in a poor to bad condition. During the early 1980’s the then landowner, who lived in the former house (house fire & demolished) next to the public house, created the recessed areas as storage. He had intended to enlarge the recessed areas further into the embankment, up to his boundary wall which was the parapet/shoulder retaining wall. The Rochdale Canal Company however informed him that if he continued to undermine the embankment he would end up with the canal running through his house. Pity no one warned him about playing with fire.

• ch-013L to ch-032L – A masonry toe retaining wall to a benched/terraced section of embankment ran adjacent to Hollins Mill Lane and tapered from 1.5 m up to 2.4 m in height, it was in a reasonable to bad condition and had a number of sections where the upper courses were missing.

• ch-019L – The site of masonry access steps to the lower terrace level on the embankment face had been removed/robbed from the wall.

• ch-019L – A tree growing on top of the lower terrace level of the embankment face had displaced a 1.3 m long x 0.8 m high area of the upper courses from the toe retaining wall and more stones were ready to fall.

• ch-026L – Leakage ran from the bottom of the toe retaining wall and up to a height of 0.6 m from the bottom of the wall, along a 4 m length of the wall with an estimated total flow rate of 0.3 l/s. Apart from the leakage running across Hollins Mill Lane, there also sounded to be more leakage running behind the wall and under the pavement of the lane.

• ch-026L – Another adjacent area of leakage also ran from the bottom of the toe retaining wall and up to a height of 0.6 m from the bottom of the wall, along a 2.5 m

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length of the wall with an estimated total flow rate of 0.2 l/s. The leakage ran across Hollins Mill Lane to form a long puddle along the edge of the lane above a blocked road gulley. The employees at an adjacent works depot complained that the leakage flow made the depot yard icy during winter.

• ch-027L – A collapsed section of toe retaining wall was 3.5 m long x 1.8 m high with adjacent lengths of wall also bulging towards the road.

• ch-028L – Leakage issued from the bottom of the toe retaining wall along a 2 m length of the wall with an estimated total flow rate of 0.1 l/s and ran across Hollins Mill Lane. A 12 m long area of slight crest settlement adjacent to a poor clay repair along the toe of the waterway wall was noted above the leakage issue. The repair had gaps and holes in the clay with visible indicators of leakage.

• ch-031L – A 15 m long x 2 m high block toe retaining wall was a blocked-up former air raid shelter that was built underground into the embankment.

• ch-032L – A recessed area into the toe was 2.5 m long and had a depth of 2.7 m into the toe. The masonry retaining/sidewalls were in a reasonable to poor condition. The recess appeared to have formed the bottom of a partially dismantled former shute.

• ch-033L – An almost vertical crack had formed at one end of the toe retaining wall near the northern corner of a masonry retaining/sidewall to a recessed area into the embankment toe (former chute). The crack was up to 50 mm wide and was considered to be an indicator of potential instability.

• ch-033L to ch-039L – A 2 m high masonry toe retaining wall to a benched/terraced section of embankment, ran adjacent to Hollins Mill Lane and was in a reasonable to poor condition.


• ch-039L to ch-052L – A masonry toe retaining wall to an earth slope face section of embankment, ran adjacent to Hollins Mill Lane, it tapered from 3.5 m down to 1.2 m in height and was in a reasonable to bad condition.

• ch-049L – The masonry upper courses and copings were missing from a 1.6 m long x 0.7 m high area of the toe retaining wall.

• ch-052L to ch-055L – A masonry embankment retaining wall in a reasonable to poor condition, ran adjacent to Hollins Mill Lane at the toe and tapered from 4 m down to 0.2 m in height. A 0.7 m high masonry parapet wall in a reasonable to poor condition was formed from a continuation of the retaining wall.

Bank Protection 1.7 The bank protection along the length inspected comprised of the following:

• ch-000L to ch-003L – A masonry waterway wall in a reasonable condition providing 600 mm of freeboard.

• ch-003L to ch-005L – The waterway wall comprised of plastic camp-shedding in a reasonable condition placed in-front of a masonry waterway wall in a poor condition providing 700 mm of freeboard. This length of bank protection was constructed beneath Hollins Mill Lane Footbridge.

• ch-005L to ch-058L – A masonry waterway wall in a reasonable condition providing 450 mm to 700 mm of freeboard.

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Slope Instability

1.8 Apart from some short sections of retaining wall that extended to the full height of the embankment, the face of the embankment was generally regular in appearance with benched upper and lower overgrown terraces with a middle tier, shoulder and toe retaining walls. Only at each end of the embankment was there earth slope faces between the shoulder and toe retaining walls, where the embankment varied between gently to moderately inclined and the slope face appeared generally stable possibly due to the extensive tree cover and exhibited no signs of major instability. The shoulder and toe were sharply defined by retaining walls that generally indicated it was in a reasonable condition. However a number of collapsed, bulging, displaced, vandalised and robbed areas of embankment middle tier, shoulder and toe retaining walls indicated areas of localised instability and potential instability. The following points were noted: • ch-005L – A bulge in the 2 m high toe retaining wall protruded over the footpath

pavement to Hollins Mill Lane. The bulged area of the wall was 3 m long with a 0.25 m bulge out of structural alignment.

• ch-012L – Two attached areas recessed into the toe had masonry sidewalls that were in a poor to bad condition. During the early 1980’s the then landowner, who lived in the former house (house fire & demolished) next to the public house, created the recessed areas as storage. He had intended to enlarge the recessed areas further into the embankment, up to his boundary wall which was the parapet/shoulder retaining wall. The Rochdale Canal Company however informed him that if he continued to undermine the embankment he would destabilise the structure.

• ch-013L to ch-032L – The middle section of slope face was benched with a middle tier retaining wall between the shoulder and toe walls and overgrown terraces. The middle tier retaining wall was 1.7 m to 2.1 m high and in a reasonable to bad condition with patches of displaced and robbed masonry.

• ch-013L to ch-032L – A masonry toe retaining wall to a benched/terraced section of embankment ran adjacent to Hollins Mill Lane and tapered from 1.5 m up to 2.4 m in height, it was in a reasonable to bad condition and had a number of sections where the upper courses were missing.


• ch-019L – A tree growing on top of the lower terrace level of the embankment face had displaced a 1.3 m long x 0.8 m high area of the upper courses from the toe retaining wall and had more stones ready to fall.

• ch-023L to ch-033L – A masonry crest shoulder retaining wall above a terraced/benched embankment face, ranged in height between 1.5 m to 2.2 m high and was in a reasonable to poor condition with patches of masonry displaced from the upper courses.

• ch-027L – A collapsed section of toe retaining wall was 3.5 m long x 1.8 m high with adjacent lengths of wall also bulging towards the road.

• ch-032L – A 2.5 m long section of masonry crest shoulder retaining wall was 1.6 m high and in a reasonable to bad condition with patches of upper courses displaced. There was no parapet/boundary wall on top of the retaining wall and the wall was located above a recess with a masonry buttress, that appeared to have formed the sidewall of a former chute.

• ch-032L – A masonry buttress that appeared to have formed the sidewall of a former chute, was in a reasonable to bad condition with patches of upper courses displaced. The buttress was located above an area with sidewalls recessed into the toe.

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• ch-033L – An almost vertical crack had formed at one end of the toe retaining wall near the northern corner of a masonry retaining/sidewall to a recessed area into the embankment toe (former chute). The crack was up to 50 mm wide and was considered to be an indicator of potential instability.


• ch-033L to ch-039L – The slope face was benched with a middle tier retaining wall between the shoulder and toe walls and overgrown terraces. The middle tier retaining wall was 1.8 m high and in a reasonable to bad condition with sections of displaced and robbed masonry. The masonry was robbed to construct waterway walls during 1986 when the canal restoration work reached this location.

• ch-049L – The masonry upper courses and copings were missing from a 1.6 m long x 0.7 m high area of the toe retaining wall.

Issues

1.9 Evidence of leakage and seepage was noted along the embankment and the following issues were noted:

• ch-012L – A mature tree was growing from the bottom of the shoulder retaining wall and leakage was issuing below onto Hollins Mill Lane at the toe. Leakage ran from the bottom of the toe retaining wall along a 2.5 m length of the wall with an estimated total flow rate of 0.3 l/s. The leakage ran across the lane to a road gulley beside the Puzzle Hall public house. Seepage with an indiscernible flow rate was also issuing from the bottom of the shoulder retaining wall adjacent to the tree. A poor clay repair along the toe of the waterway wall was noted above the tree and it was considered that tree root penetration was the main cause of the leakage, in conjunction with slope face settlement that resulted from modifications to the toe retaining wall. The clay repair had gaps and holes in the clay with visible indicators of leakage. After the canal was re-opened to navigation during the mid to late 1990’s, the local authority canal restoration team based at Callis Mill in Hebden Bridge, had a number of attempts at curing this particular leak (which was worse in appearance) due to complaints from the then landlord of the public house.

• ch-026L – Leakage ran from the bottom of the toe retaining wall and up to a height of 0.6 m from the bottom of the wall, along a 4 m length of the wall with an estimated total flow rate of 0.3 l/s. Apart from the leakage running across Hollins Mill Lane, there also sounded to be more leakage running behind the wall and under the pavement of the lane.

• ch-026L – Another adjacent area of leakage also ran from the bottom of the toe retaining wall and up to a height of 0.6 m from the bottom of the wall, along a 2.5 m length of the wall with an estimated total flow rate of 0.2 l/s. The leakage ran across Hollins Mill Lane to form a long puddle along the edge of the lane above a blocked road gulley. The employees at an adjacent works depot complained that the leakage flow made the depot yard icy during winter.

• ch-028L – A 12 m long area of slight crest settlement with a fall of 0.1 m was noted adjacent to a poor clay repair along the toe of the waterway wall (which had also settled to a freeboard of 450 mm from 500 mm). The repair had gaps and holes in the clay with visible indicators of leakage.

• ch-028L – Leakage issued from the bottom of the toe retaining wall along a 2 m length of the wall with an estimated total flow rate of 0.1 l/s and ran across Hollins Mill Lane. A 12 m long area of slight crest settlement adjacent to a poor clay repair along the toe of the waterway wall was noted above the leakage issue. The repair had gaps and holes in the clay with visible indicators of leakage.

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2.0 Associated Structures

2.1 The following structures were located along the length inspected:

• Hollins Mill Lane Foot Bridge – A long standing foot bridge crossing the canal at ch-004. No functional location was recorded in SAP for this structure.

• RD-001-009-R Cutting 1 – SAP records this structure as having a Condition Grade C established 25 August 2006. No other details were recorded in SAP.

• RD-002-001, Sowerby Long Bridge – SAP records this structure as having an Impairment Score of 27 established 10 April 2000 and a Condition Grade D. established 16 February 2005.

3.0 Comments on Risk

3.1 The embankment is situated directly above Hollins Mill Lane, a number of works premises and a public house with the River Calder immediately beyond. Should the embankment fail and the canal breach the water may run through an affect any of the business premises before running into the river to be carried away. As the canal pound is 4.2 km long there is a potential to loose a large quantity of water. Disruption to the towpath located on the embankment would also occur. A Consequence of Failure Grade of 4 is therefore considered appropriate for this structure.

3.2 The lowest effective freeboard was 0.45 m which was located at ch-028L adjacent to a 12 m long area of slight crest settlement, however, the current potential for overtopping is minimal due to the reasonably adequate freeboard, the large capacity of this canal pound, the three overflows and the large bywash located on this pound.

4.0 Estimated Costs & Works Recommendations

Short term (<1 yrs) Repair parapet/boundary walls. Estimated cost £39,000. Repair embankment shoulder retaining wall. Estimated cost £4,000. Repair embankment Middle tier retaining wall. Estimated cost £10,000. Repair the access steps on the embankment face. Estimated cost £2,000. Dismantle and re-build bulge in toe retaining wall. Estimated cost £2,500. Rebuild retaining walls to recessed areas of embankment. Estimated cost £6,000. Repair embankment toe retaining walls. Estimated cost £5,000. Remove trees from the embankment crest/shoulder. No additional costs associated with this work. Repair leakage associated with tree roots. Estimated cost £3,000. Investigate and repair leakage associated with a settled area of crest. Estimated cost £4,000. Install locking barrier to vehicular access point onto embankment crest. Estimated cost £2,000. Monitor crack in toe retaining wall. No additional costs associated with this work. Monitor the slope face and toe for any potential leakage/seepage or instability. No additional costs associated with this work.

Medium Term (1-5 yrs) None

Long Term (5-10 yrs) None

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Recommendations

4.1 A 0.4 m to 0.9 m high masonry parapet/boundary wall in a reasonable to bad condition ran throughout the embankment and was generally formed from a continuation of the embankment shoulder retaining wall. The parapet wall not only defined the boundary but more importantly prevented a fall from height above the shoulder retaining wall. The parapet wall had a number of vandalised/displaced sections of missing masonry at the following locations: ch-007L a 3 m length; ch-009L a 1.5 m long hole; ch-012L a 2 m long hole; ch-018L a 2 m length; ch-019L a 1.8 m length; ch-021L a 1.2 m length; ch-022L a 2.6 m length; ch-037L a 1 m length; ch-038L a 0.6 m length; a 1 m length; ch-042L a 2 m length; ch-043L a 10 m length; ch-046L a 11 m length; ch-049L a 4 m length & ch-051L a 3 m length. The parapet wall was completely missing from along the top of a section of masonry crest shoulder retaining wall between ch-023L and ch-033L. It is therefore recommended the parapet wall be repaired/reinstated to prevent a fall from the top of the shoulder retaining wall and to maintain the integrity of the shoulder retaining wall which is also loosing stones from the exposed upper courses. Estimated cost £39,000.

4.2 The parapet wall was completely missing from along the top of a section of masonry crest shoulder retaining wall between ch-023L and ch-033L and the shoulder retaining wall had patches of masonry displaced from the exposed upper courses. This section of shoulder retaining wall was located above a terraced/benched embankment face and ranged in height between 1.5 m to 2.2 m. It is recommended that any trees growing directly on top or from the retaining wall be removed and that the shoulder retaining wall be repaired to maintain the integrity of the wall as it was losing stones from the exposed upper courses. Estimated cost £4,000.

4.3 The middle section of slope face was benched with a middle tier retaining wall between the shoulder and toe walls between ch-013L to ch-039L. The middle tier retaining wall was 1.7 m to 2.1 m high and in a reasonable to bad condition with patches of displaced and robbed masonry. It is recommended that any trees growing directly on top of the retaining walls be removed and that the middle tier retaining wall be repaired to maintain the integrity of the wall, as it was loosing stones from the exposed areas. Estimated cost £10,000.

4.4 The masonry access steps located on the benched embankment face at ch-029L between the towpath and Hollins Mill Lane were in a reasonable to bad condition. The short interconnecting flight of steps between the landing areas for the upper and lower flights were in a bad condition with displaced patches of masonry. It is recommended that the displaced patches of masonry be repaired to maintain the integrity and safety of the access steps. Estimated cost £2,000.

4.5 A bulge in the 2 m high toe retaining wall at ch-005L protruded over the footpath pavement to Hollins Mill Lane. The bulged area of the wall was 3 m long with a 0.25 m bulge out of structural alignment. It is recommended that this section of retaining wall be dismantled and rebuilt to the correct wall batter so as to prevent failure of the retaining wall and embankment at this location. Estimated cost £2,500.

4.6 Two attached areas recessed into the embankment toe at ch-012L had makeshift masonry sidewalls that were in a poor to bad condition. During the early 1980’s the then landowner, who lived in the former house (house fire & demolished) next to the public house, created the recessed areas as storage. It is recommended that the makeshift sidewalls to the recessed areas be dismantled and rebuilt to the correct wall batter so as to prevent failure of the embankment at this location. Estimated cost £6,000.

4.7 The masonry embankment toe retaining walls to a benched/terraced section of embankment between ch-013L to ch-032L and a section of embankment with an earth slope face between ch-039L to ch-052L ran adjacent to Hollins Mill Lane and ranged from 1.2 m to 3.5 m in height, the toe walls were in a reasonable to bad condition and had a number of sections where the upper courses were missing. At ch-019L a tree growing on top of the lower terrace level of the embankment face had displaced a 1.3 m

ESPI/0607/7600/RD-001-010-L

long x 0.8 m high area of the upper courses from the toe retaining wall and more stones were ready to fall. A collapsed section of toe retaining wall at ch-027L was 3.5 m long x 1.8 m high with adjacent lengths of wall also bulging towards the road. At ch-049L the masonry upper courses and copings were missing from a 1.6 m long x 0.7 m high area of the toe retaining wall. It is recommended that any trees growing directly on top of the toe retaining walls be removed and that the displaced, collapsed and bulging sections of the toe walls be repaired to maintain the integrity of the walls and prevent failure of the embankment. Estimated cost £5,000.

4.8 A mature tree was growing on the embankment shoulder at ch-017L and the tree roots were causing the shoulder surface to bulge. A number of other smaller trees were located along the shoulder nearby. It is recommended that the trees be removed and any remaining roots treated with a suitable herbicide, as part of the general maintenance works programme, before they cause greater damage to the shoulder retaining wall and potentially create leakage routes. No costs are associated with this work.

4.9 A mature tree was growing from the bottom of the shoulder retaining wall at ch-012L and leakage was issuing below onto Hollins Mill Lane at the toe. As previous repairs at this location have failed it appears to indicate that the leakage problem is deeper seated and work to replace the tree root fissured clay puddle lining within the bank or canal bed is recommended. Removal of the mature tree from the bottom of the shoulder retaining wall should be undertaken first and the remaining tree stump treated with a suitable herbicide. It is recommended that the canal water level be lowered and a fresh start made by removing all the material of the previous repair. Once the potential load/surcharge/leverage of the tree has been removed from the crest/shoulder retaining wall the adjacent crest should be excavated to remove the roots and tree root fissured clay to a depth of 2 m within the embankment crest/bank or canal bed at this location. It is also recommended that the puddle trench work above the issue be continued for a length of 10 m in each direction beyond directly above the issue, totalling 20 m of puddle trench work. A section of waterway wall may have to be dismantled and rebuilt as the clay lining under the wall and along the edge of the canal bed may require replacement. This work could be undertaken as part of the general maintenance works programme and is likely to require the lowering of the canal water level. Estimated cost £3,000.

4.10 Two leakage issues ran from the bottom of the toe retaining wall at ch-026L and up to a height of 0.6 m from the bottom of the wall. A 12 m long area of slight crest settlement at ch-028L was also noted adjacent to a poor clay repair along the toe of the waterway wall. Directly below the crest settlement leakage also issued from the bottom of the toe retaining wall. The crest settlement and the leakage below appeared to be directly linked and it is not impossible for the leakage at ch-026L to be associated with the area of settlement, as the toe is 5.5 m below canal water level. The canal bank in front of this area should be tested with florescene dye to determine which issues at the toe are linked to this area of settlement. If the issues do not appear to be linked to the one area of crest, further dye testing will be required to confirm the extent of the leakage along the canal bank, it should be followed with work to repair the clay puddle lining within the crest/bank or canal bed. It is recommended that the canal water level be lowered and a fresh start made by removing all the material of the previous repair. To cure the leakage/seepage it is recommended that the puddle clay lining (above and adjacent to the issue/s) within the embankment crest and canal bed be exposed. This should then be examined for soft spots, cracks, desiccation and settlement. Where necessary the clay lining should be exposed to a depth of between 1 m and 2 m and replaced where required. It is also recommended that the puddle trench work above the issues be continued for a length of 10 m in each direction beyond directly above the issues and this is likely to involve a total 40 m of puddle trench work in this instance. After the removal of the crest surface it may be found that the clay lining immediately below the crest may also require raising where settlement has occurred. It is recommended that the compacted puddle clay lining be raised to at least 300 mm above water level pending the findings of experienced waterway personnel. This work could be undertaken

ESPI/0607/7600/RD-001-010-L

as part of the general maintenance works programme by experienced personnel or offered to a contractor with clay puddling experience. Estimated cost £4,000.

4.11 A roadside gap in the boundary wall between ch-055L to ch-057L permits unwanted vehicle access onto the embankment crest. It is recommended that a gate or a line of lockable bollards be installed across the gap to prevent unwanted vehicle access onto the crest, this would improve safety, prevent vehicles and large items of rubbish from being dumped in the canal, prevent vehicle damage to the crest and prevent masonry from the parapet wall from being stolen. Estimated cost £2,000.

Investigations/Monitoring

4.12 An almost vertical crack had formed at one end of the toe retaining wall near the northern corner of a masonry retaining/sidewall to a recessed area into the embankment toe (former chute) at ch-033L . The crack was up to 50 mm wide and was considered to be an indicator of potential instability and the wall will require monitoring for further dilapidation. The installation of “tell tales” across the crack or regular measurement of the crack width should form part of this monitoring. This work should form part of the Length and Annual Inspection processes.

4.13 Monitoring of areas of leakage/seepage along the embankment toe and slope face is recommended so that it can be inspected for any further increase or decrease. The shoulder, slope face and toe should also be monitored to check that any deformation of the retaining walls occurring does not develop into hazardous areas of instability. Loosened areas of parapet wall masonry should also be monitored and reported so that it may be secured/stabilised as soon as possible to prevent further loss of the wall. This monitoring should form part of the Length Inspections. If further instability or increase in leakage flow is detected it should be reported immediately and consideration should be given to commencing with the recommended works as soon as possible. No additional costs are associated with this work.

ESPI/0607/7600/RD-001-010-L

Condition Grade Embankment 2 D Consequence Of Failure Grade Embankment 2 4 Serviceability Grade Embankment 2 1 Recommendations For Future Inspections (Length & Annual) Future inspections to be carried out in accordance with AIP2005. Inspectors should check known areas of potential leakage/seepage reporting any significant changes. Length Inspectors should also include visual monitoring for further loss of the parapet wall, any retaining wall or tree deformation occurring on the slope face, paying particular attention for possible settlement along the crest/shoulder and any potential lower slope face/toe wall instability. Any of these indicators should be reported immediately. Next Principal Inspection 2016 or following major remedial works.

ESPI/0607/7600/RD-001-010-L

ESPI/0607/7600/RD-001-010-L

SAP FUNCTIONAL LOCATION CLASSIFICATION RECORD FOLLOWING PRINCIPAL INSPECTION

Functional Location : RD-001-010-L Description : Hollins Mill Lane Embankment 2 Class Type : 003

Characteristic Description : Value Access Details : Include Asset in AIP : Yes Alternative Names : Has Asset Been Confirmed : Yes Nature of BW Interest : BW Owned Asset : No Condition Grade : D Consequence of Failure : 4 Date Listed : Health & Safety Details : Heritage Asset : Statutory Listing Document : Intermediate Inspection Date : None Impairment Score : None Impairment Survey Sheet No. : Embankment Proximity to Wildlife Site : K Score : None Listing Grade : Statutory Listing Name : Owner : % Residential Occupancy : Principal Inspection Date : 26.09.2006 Remarks : Inspector: Carl Conwell Serviceability : 1 Topographic Identifier : TRIM Reference : GIS Object Available : Yes Scheduled Grade : Date Scheduled : Statutory Scheduled Name : Statutory Scheduled Document Ref : Min Depth of Water at NWL : Min Navigation Width of Canal : 9.000 m Canal NWL : Full Length : 540.000 m Max Height Original GL Below WL : 5.500 m Min Width OS Toe to Water Edge : N/A Min Width TP Crest to Water Edge : 2.500 m Max Slope Angle : 31o Type of Construction : Sidelong Embankment

Earth Structures Inspection Team

PHOTOGRAPHS

FILE REF: RD-001-010-L STRUCTURE: Hollins Mill Lane Embankment 2 DATE: 26.09.2006 Rochdale Canal

ch-004L - View south-east towards the start of the embankment from Hollins Mill Lane Footbridge, note a new section of slope face on the site of a demolished building.

ch-012L - View of leakage running across Hollins Mill Lane towards the Puzzle Hall Inn, also note the makeshift recessed area in the embankment toe beside the leakage.


PHOTOGRAPHS


ch-012L - View of seepage issuing from the bottom of the shoulder retaining wall, adjacent to a mature tree growing from the bottom of the wall.

ch-012L - A view of leakage holes in a clay repair at the base of the waterway wall, which have drawn floating tree litter.


PHOTOGRAPHS


ch-019L - View north-west along the toe, a patch of greenery in the retaining wall is where steps were stolen from the wall and further along stones were displaced by a tree growing on top of the wall.

ch-022L - A view of the three tier retaining walls that form a cross-section of the embankment face.


PHOTOGRAPHS


ch-026L - View of leakage issuing from the bottom of the toe retaining wall.

ch-027L - View of a collapsed and missing section of toe retaining wall and a view of the above leakage running across the road.


PHOTOGRAPHS


ch-028L - View of another area of leakage issuing from the toe retaining wall, also note the towpath access steps nearby.

ch-031L - View along the middle tier retaining wall and towards an area from which the masonry has been stolen.


PHOTOGRAPHS


ch-032L - View from the embankment shoulder down a former chute that was recessed into the embankment face.

ch-033L - View of a crack running down an end section of the toe retaining wall adjacent to the above former chute recess.


PHOTOGRAPHS


ch-046L - View south-east along the crest, note the vandalised, missing parapet wall and the potential fall risk.

ch-049L - View of another section of vandalised and displaced embankment parapet wall.

0m 20m 40m

N

60m 80m 100m

EARTH STRUCTURE PRINCIPAL INSPECTION

Crown copyright. Unauthorised reproduction infringes Crown copyright and may lead to prosecution or civil proceedings. British Waterways, 100019843, 2005.This map is based upon Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty's Stationery Office c

REVISIONS

0113 281 6886Telephone: 0113 284 5200

Technical DirectorateGeotechnical and Earth Structures TeamFearns Wharf

Leeds LS9 8PBNeptune Street

Fax:

DATE OF INSPECTION PREVIOUS INSPECTION

DATE

DWG No.

CHECKED BY

DRAWN BY INSPECTED BY

APPROVED BY

REVISION

SCALE

ROCHDALE CANAL

EMBANKMENT 2, Hollins Mill LaneSheet 2 of 2

26.09.06 N/A

S.C. C.C.

C.C. A.F.

17.10.06 1:1250

RD-001-010-L/ESPI/01

Rochdale Canal

BM 87.75m

87.8m

Sluice

Weir

Sluices

Und

Path

CR

SowerbyLong Bridge

93.0m

HOLLINS MILL

86.0m

BM 84.21m

Towing Path

83.2m

Marton Heights

Mill

Playing Field

5658

555759

505254

4951

LANE

53

(dis)

Cliff

Cliff

Path (um)

Path

60

Cycle Track

Playing Field

129

137

127

123

INDUSTRIALROAD

Marton Heights

117.7m

114.9m

BM 116.24m

Hollings HillHOLLINS MILL LANE

BM 105.42mCanal View

HOLLINS LANE

111.3mTrough

LB

107.0mHill

Top

The Bungalows

2 4

1 3

5

1311

9

75

3

1

79 73 71 69

676563

5854

54a

52a

52

8

5

38

30

28

26

29

27

25

24

22

20

35

33

31 36

34

32

41

39

37 42

40

38

75

The

Bungalows

Cliff

Ward Bdy

Boro Const Bdy

Co Const Bdy

CR

Marton HeightsWood View

116.4m

109.1m

Depot

108.2m

El Sub Sta

Bank Royd

121.0m

HOLLINSLANE

Scott Bank

105.5m

El Sub Sta

El Sub Sta

60

72

82

88

90

96

246

135

53

51

49

4547

70

14a

14

10

2

1

68

43

41

62

81.7m

81.1m

INDUSTRIAL ROAD

Allot Gdns

Mill

Works

Cliff

49

61

71

77

Playing Field

59

119

111

107

109

Track

80a

80d

78e

78a

DW

47c

47

47b

47a

OLIVER CLOSE

1

9

5

M2

U2

F450

V1-3/0

+0.8

22°

M2

F500

M2

F500

M2

F600M2

F600M2

F500M2

F500

M2

F600

M2

F450

M2

F500

M2

F500

U2

U2-3

U2-3

U2

U2

U2

U2-3

M2

M2

25°

24°

31°

V3/2

V1/0

V2-3/2

V1/0

V3-4/2

V3-4/2-3V1-3/0

V3/2V3/2

V3/2

V3-4/2

V1/0

V1/0

+1+0.6

-23.4

+0.6

-3.5+0.65

-4

-4.5

+0.7

+0.6

+0.6

-5

-5

-5.5

2.5

2.8

3

32

3.5

3

3

2.63

V1-3/0

2.43 3.8

4

3

3.4

3.4

24

+0.65

+0.6

+0.5

+0.55

V3-4/2V3/2

V1-3/0V3-4/2V3-4/2

V1/1V3-4/2-3

V3-4/2-3

-5.5

-5

M2

M3

M2 crest shoulder retaining wall 0.6m to 1.5m high plus a 0.4m to 0.9m high M2-4 parapet wall on top

Ch | 030

Ch | 040

Ch | 050

B

C

A

Section of parapet wall completely missing (area from point C to point A)

M2-4 parapet wall 0.4m high with 2.6m length vandalised and displaced section


Former air raid shelter blocked off

M2-4 toe retaining wall 1.5m to 2.4m high, a number of sectionswhere upper courses are missing (area from point B to point D)

Recess into embankment toe 2.5m long x 2.7m deep withM2-3 retaining side walls, possibly a former chute

Vertical crack at end/return of toe retainingwall with a gap of up to 50mm wide

Site of former robbed steps

Terraced section of embankment. M2-3 lower retaining wall 2m high.M2-4 mid-face retaining wall 1.8m high with sections of masonrydisplaced and robbed. M2 upper crest shouler retaining wall.

M2-4 retaining wall1.2m to 3.5m high

M4 missing upper courses and coping from a 1.6m long x 0.7m high section of retaining wall

M2-4 retaining wall 1.2m to 3.5m high

M2-3 retaining wall 0.2m to 4m high plus an M2, 0.7m high parapet on top

Gap in boundary wall permits un-wanted vehicle access

3m length of M4 masonry parapet wall vandalized with masonry displaced and missing



Leaning tree obscuring navigation



Three holes (0.6m long, 1m long, and 1m long) of displaced M4 from parapet wall

Section of parapet wall completely missing (area from point A to point C)

M2-3 crest shoulder retaining wall 1.5m to 2.2m high with patches ofmasonry displaced from upper courses (area from point B to point D)

M2-4 steps to towpath

Slight settlement along a 12m length section of crest as muchas 0.1m. Poor clay repair along toe of waerway wall withgaps and holes in the clay and visible signs of leakage.M3 buttress

M2-4 crest shoulder retaining wall 1.6m high with patches of upper courses displaced

0m 20m 40m

N

60m 80m 100m

EARTH STRUCTURE PRINCIPAL INSPECTION

Crown copyright. Unauthorised reproduction infringes Crown copyright and may lead to prosecution or civil proceedings. British Waterways, 100019843, 2005.This map is based upon Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty's Stationery Office c

REVISIONS

0113 281 6886Telephone: 0113 284 5200

Technical DirectorateGeotechnical and Earth Structures TeamFearns Wharf

Leeds LS9 8PBNeptune Street

Fax:

DATE OF INSPECTION PREVIOUS INSPECTION

DATE

DWG No.

CHECKED BY

DRAWN BY INSPECTED BY

APPROVED BY

REVISION

SCALE

ROCHDALE CANAL

EMBANKMENT 2, Hollins Mill LaneSheet 1 of 2

26.09.06 N/A

S.C. C.C.

C.C. A.F.

17.10.06 1:1250

RD-001-010-L/ESPI/01

Mill

Playing Field

108.2m

BEECH ROAD

WALLIS S

TREET

EGERTON STREET

PEEL STREET

NEWTON STREET

BM 124.00m

LB

122.5m

MOUNT STREET

UPPER FOUNTAIN STREET

119.8m

128.0m

105.5m

El Sub Sta

El Sub Sta

BM 104.79m

101.8m

Dale Street

El Sub Sta

Houghton

Works

HOLLINS

MILL LANE

BM 82.68m

Works

Works

El Sub Sta

River Calder

Works81.4m

BM 81.74m

Bull'sHead

17

19

181614

4

10

7

21

1 to 87

11315

29

1

9 2

12

1

9

2

16

36

48

60

72

52

27

25a

33

25

23

9

7

1

2

10

18

17

9

1

27

10

45

20

55

1

2 1

212

24

36

16 18

14

12

16

12

1

56

2

12

41

62

39

North Lea

Hollins Bank

9

1

19

National

SpiritualistChurch

and

Lyceum

25 21

3023

44

19

13

9

40

38

24

2018

16

57

1

15

Towers

Hollins Mill Lane

Foot Bridge

Mount Terrace

22

26

Allotment

Gardens

Rochdale Canal

Towing Path

82.0m

Works

Pavilion

Cricket Ground

Trough

81.7m

81.1m

Posts

Garage

PH

82.0m

31

33

35

Edith's View

Chy

Tank

2

ElSub Sta

14

CORPORAT

ION STRE

ET

Surgery

GREENUPS TERRACE

WALTON STREET

Works

81.4m

1BM 81.69m

Car Park

INDUSTRIAL ROAD

TCB

Mill

Works

Cliff

TUEL LANE

Depot

Cliff

Ladstone

Towers

1 to 87

Playground

Chapel ofRest

Warehouse

Hoppers

Tank

Boundary Works

Cliff

Works

Mill

Works

Cliff

Works

Path

St Paul's

Methodist Church

49

61

71

77

Beech Royd

Town H

all Ct

22

28

Playing Field

47c

47

21

33

47b

47a

1

F500M2

F500

M2

F600

M2

F450

M2

F500

M2

F550

M2

F550

M2

F500

M2

F600

M2

F700

M2

F700P2/M3

F600

M2

F500

U2

U2

U2-3

U2-3

U2-3

U2

U2-3

U2-3

U2-3

M2

M2

V3/2V3/2

V3/2

V3-4/2

V1/0

+0.6

+0.6

-5

-5

-5.5

32

3.5

3

3

2.63

V1-3/0

2.43 3.8

4

3

3.4

3.4

24

3.4

3.4

+0.65

+0.6

+0.5

+0.55

+0.6

+0.65

V3-4/2V3/2

V1-3/0V3-4/2V3-4/2

V1/1V3-4/2-3

V3-4/2

V1/1V3/2-3

V1/1

V3-4/2-3

V4/2

V3/2

-5.5

-5

-4.5

-4.5

-5

-5

24°

29°

26°

31°

2.6

3

3

3

V1-3/0

V3/2

V3-4/2V1-3/0

V4/2

V1/0

V2-3/0

+0.55

+0.6

+0.7

+0.6

-5

-5

V3-4/0

M2

M3

Ch | 000

Ch | 004

Ch | 010

Ch | 020

Ch | 030

B

C

A

D

Section of parapet wall completely missing (area from point C to point A)

E

M2/B2-3, 6m high retaining wall plus a 1.2m high M2 parapet on top

Minor/small damp patches on lower retaining wall at location of an old leakage issue, still cured (good repair)

M2 shoulder retaining wall 1.2m to 1.5m high plus an M2, 1.1m high parapet on top

Former building demolished

M2 toe retaining wall 2.3m high

M2 access steps with S2 railings to FB

M2 crest shoulder retaining wall 2m to 3.5m high plus an M2-3, 0.6m to 0.8m high parapet wall (area from point E to point D)

Bulge in toe retaining wall 3m long x 0.25m bulge

Leakage from bottom of toe retaining wall along a 2.5m length of wall,total flow of 0.3 l/s across road to road gulley beside public house

Mature tree growing from bottom of shoulder retaining wall with leakage below potential root penetration

M3-4 former niche/recess with retaining side walls

M2-3 toe retaining wall 1.4m to 2m high (area from point D to point E)

M2-4 toe retaining wall 1.5m to 2.4m high, a number of sectionswhere upper courses are missing (area from point D to point B)

M3-4 site of former steps removed from wall (robbed)

Tree displacing upper courses of wall1.3m long x 0.8m high with more stones ready to fall

M2-4 mid-face embankment retaining wall 1.7m to 2.1m high with patchesof displaced and robbed masonry (area from point B to point D)

Leakage from toe retaining wall up to 0.6m from bottom of wall over a 2.5m lengthof wall with a flow of 0.2 l/s. Road gulley blocked and long puddle formed on roadacross from leakage. Flow also makes Works Yard icy in winter.

Leakage from toe retaining wall up to 0.6m height from bottom of wall over a 4m long section ofwall with a flow of 0.3 l/s (sounds like more leakage flowing behind wall and under pavement)



Collapsed section of toe retaining wall 3.5m long x 1.8m high with adjacent lengths of wall also bulging

Leakage issue from bottom of wall with a flow of 0.1 l/s

Former air raid shelter blocked off

M2-4 toe retaining wall 1.5m to 2.4m high, a number of sectionswhere upper courses are missing (area from point B to point D)

Recess into embankment toe 2.5m long x 2.7m deep withM2-3 retaining side walls, possibly a former chute

Vertical crack at end/return of toe retainingwall with a gap of up to 50mm wide

Site of former robbed steps

Terraced section of embankment. M2-3 lower retaining wall 2m high.M2-4 mid-face retaining wall 1.8m high with sections of masonrydisplaced and robbed. M2 upper crest shouler retaining wall.

M2-4 retaining wall1.2m to 3.5m high

M2-4 steps to towpath

Slight settlement along a 12m length section of crest as muchas 0.1m. Poor clay repair along toe of waerway wall withgaps and holes in the clay and visible signs of leakage.M3 buttress

M2-4 parapet wall 0.4m to 0.9m high with 1.8m length vandalised and displaced section

M2-4 parapet wall 0.4m to 0.9m high with 2m length vandalised and displaced section

Mature tree growing on crest shoulder, roots causing shouldersurface to bulge. Also other smaller trees along shoulder.

M2-3 crest shoulder retaining wall 1.5m to 2.2m high with patches ofmasonry displaced from upper courses (area from point B to point D)

M2-4 parapet wall 0.4m high with 2m length hole

Separate issue from bottom of shoulder retaining wall, flow indiscernible

Poor clay repair along toe of waterway wall with gaps and holes in the clay and visible signs of leakage

M2-4 parapet wall 0.4m high with 1.5m length hole

M2-4 parapet wall 0.4m high with 3m length vandalised and displaced section

principal inspection report - whatdotheyknow€¦ · hebble navigation. the ring connects to the...

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