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Strategic Structural Maintenance 2015/16

(Highways and Harbours)

January 2015

Version 2.0

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Introduction The Highway Services Division believes that routine maintenance of the Department’s structures has been neglected for many years. This is reducing the life of these structure and, if allowed to continue, risks catastrophic failures in the future. The Division, in discussions with Treasury, identified a level of funding required to carrying out long-term structural maintenance. The Strategic Structural Maintenance capital fund was approved by Tynwald in February 2015. The Strategic Structural Maintenance capital money is for basic maintenance to ensure the long-term integrity of the highway and harbour structures. Other works may take place on structures that are not within the scope of this report or funding. Examples include: minor operational, routine or safety maintenance, work to improve the public, operational or visual amenity; work to increase business, or operational capability, work to upgrade facilities and other specific capital investments.

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Structure Name: Jurby East Bridge (SN 1103) Location: B3 East Jurby (E3956, N9926) Budget estimate: £60,000

Description: Jurby East Bridge is a single span reinforced concrete slab on concrete abutments and has been assessed as failing due to differential settlement. A design has been completed for a replacement structure that is capable of carrying 40 tonnes moving loads. This has been designed in the form of a reinforced concrete culvert. Proposed Works:- Demolish existing structure Re-construct the riverbed and embankments Construct new concrete culvert, parapet walls and wing walls Re-surface bridge deck

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Structure Name: Ramsey Sea Wall Reconstruction (SN 3883) Location: Mooragh Promenade Budget estimate: £200,000

Description: Ramsey Sea Wall retains and protects Mooragh Promenade. The recent storms have caused a large part of the wall and pavement to collapse. Emergency works in the form of placing rock armour along the face of the damaged area have been undertaken but the wall now needs to be reconstructed. A design for this work has been prepared and a contractor engaged. Proposed Works:- Construct new retaining wall in reinforced concrete Reconstruct pavement

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Structure Name: Bay Ny Carrickey Sea Wall undermining repairs (SN 1508) Location: Gansey Promenade (E2362, N6875) Budget estimate: Underpinning - £130,000

Description: Long lengths of the Bay ny Carrickey retaining wall is undermined at the toe and requires underpinning. Each of the affected areas will require different forms of construction to repair. A design has not yet been undertaken. Proposed Works:- Remove large amounts of loose material from voids at the base of the wall Construct a new deeper toe in front of the existing wall Underpin wall with concrete behind the toe filling the voids

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Structure Name: Strathallan Sea Wall Location: Douglas Promenade Budget estimate: £90,000 (E3919, N7735)

Description: The sea wall at the Strathallan end of Douglas Promenade suffers damage from wave action and parts of the wall are showing signs of distress with some of the blocks coming loose. The wall needs to be repaired in order to maintain its integrity and to continue to provide protection to the highway. Proposed works:- Fix formwork to face of wall locally and pour a new reinforced concrete face. Alternatively, repairs may be undertaken using traditional formwork and reinforced concrete.

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Structure Name: Ballanard Road Bridge Location: Ballanard Road (E3742, N7887) Budget estimate: Re-construct wing wall £30,000

Description: The bridge at Ballanard Road is constructed as a masonry arch and is in overall very good condition. However, one of the wing walls is leaning badly and has caused the pavement to sag noticeably. The wall needs to be taken down and reconstructed with a new foundation. The pavement also needs to be reconstructed. Proposed Works:- Take down existing wall and reconstruct in Manx stone Reconstruct pavement

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Structure Name: King Edward VIII Pier (SN 2204) Location: Douglas Harbour (E3860, N7514) Budget estimate: Pointing - £5,000 Step repairs - £5,000 Concrete

repairs - £12,000 Platform refurbishment - £20,000 Total Cost £42,000

Description: There are substantial areas to all faces of the breakwater requiring pointing. The concrete steps are all in need of refurbishment and require new timber edgings. A specification has been issued for this work. There is some scour and washout at the base of the pier adjacent to the linkspan and this will need further investigation and some underwater concrete repairs. The steel access platforms are in need of refurbishment and require replacement of fixings, rust removal and preparation works prior to re-painting. Proposed Works: Pointing of all faces where required Repairs to steps and railings Underwater concrete repairs Refurbishing of steel platforms

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Structure Name: Victoria Pier (SN 2209) Location: Douglas Harbour (E3877, N7525) Budget estimate: Pointing - 5,000 Step repairs – £5,000 Concrete

repairs £15,000 Total Cost £25,000

Description: There are substantial areas to all faces of the breakwater requiring pointing. The concrete steps are all in need of refurbishment and require new timber edgings. A specification has been issued for this work. Most of the steel handrails on the steps are badly corroded and in need of replacement. There is a hole at the base of the pier with a large cavity behind. This will need further investigation and some underwater concrete repairs. The deck improvement works proposed in the original report have now been deemed as un-necessary. Proposed Works: Pointing of all faces where required Repairs to steps and railings Underwater concrete repairs

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Structure Name: Battery Pier (SN 2212) Location: Douglas Harbour (E3892, N7499) Budget estimate: Concrete repairs & pointing - £10,000, Deck replacement - £95,000 Step repairs - £5,000 Total Cost £110,000

Description: The deck of the pier at the root is in poor condition and needs excavating to allow a new concrete deck to be provided. The outer face of the pier is in reasonably good condition but is in need of pointing over most of its area. Some of the facing blocks have substantial cracks showing that will need to be raked out and filled. There are also cracks in the steps that will require similar repair work. The timber fenders at the end of the pier are rotten at the lower ends and need refurbishing or replacing, however, this work is not a funding priority at this time. Proposed Works: Repairs and pointing to outer face Resurface deck area at root of pier with new concrete slab (approx. 975m2) Repairs to steps and railings

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Structure Name: Fort Anne Jetty (SN 2219) Location: Douglas Harbour (E3862, N7509) Budget estimate: Phase 1 - £35,000 Phase 2 - £56,000 Total Cost £91,000

Description: Fort Anne Jetty is currently used by anglers and small boats tie up against it. Its construction is of a reinforced concrete frame of columns and beams with a timber deck. The timber deck is currently closed to the public due to its very poor condition. The concrete frame is also in poor condition with numerous areas of spalling concrete requiring repair with a polymer modified or epoxy repair mortar. In addition to repairing the structure, there is an opportunity to improve the structure to provide more berths. Undertaking the phase 1 repairs now will reduce future maintenance costs and extend the life of the structure substantially. A full specification with drawings has been prepared for all of this work. Proposed Works: Phase 1 (Maintenance works) Replace timber deck with “Govadeck” plastic decking Replace damaged timber fenders Repair concrete structure with Renderoc LA55 Phase 2 (Improvement works) Additional timber walings and posts Additional “D” shaped rubber fenders

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Structure Name: Circus Beach (SN 2449) Location: Douglas Harbour (E3862, N7509) Budget estimate: £65,000

Description: Circus Beach is the main marshalling area for vehicles boarding Steam Packet vessels and is utilised as a trailer park. The surface is constructed from pre-cast concrete paviours. Two traffic lanes guide boarding vehicles, via the linkspan bridges, onto berths 1 and 5. The entire area of the marshalling area shows signs of settlement and the paviours are in very poor condition with large areas of cracked blocks. The traffic lane leading to berth 5 is in particularly poor condition with a large amount of settlement of the paviours and a majority of them cracked or split. The uneven surface is causing wagons to bounce as they run onto the linkspan causing damage to both themselves and the linkspan. Proposed Works Excavate existing paviours within the traffic lane leading up to the linkspan and re-level the sub-base to provide a new level surface suitable for traffic. (approx. 500m2)

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Structure Name: Castletown Outer Breakwater (SN 2393) Location: Castletown Harbour (E2666, N6729) Budget estimate: £35,000

Description: The breakwater provides an essential defence to Castletown Harbour providing protection to the inner and outer harbour areas from severe weather. It is in generally good condition overall. The deck recently suffered damage during the winter storms but this has since been repaired and is now in very good condition with no sign of any settlement. The parapet is also in good overall condition. The outer face and end of the breakwater have been faced in sprayed concrete and for the most part is in good overall condition. However, there has been some recent damage to the middle section and base of the external face with large patches of concrete missing. This needs to be repaired to halt any further damage. What can be seen of the inner face is in overall good condition, however the lower part of the wall and foundations are not visible due to weed growth. Proposed Works: Repair damaged patches on outer face using sprayed concrete Remove vegetation from inner face and re-inspect Point joints on inner face

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Structure Name: Irish Quay (SN 2395) Location: Castletown Harbour (E2667, N6737) Budget estimate: £15,000 – £30,000 (depending on area)

Description: The south face of the quay has numerous areas where the joints are missing mortar leaving large gaps between the blocks. The entire face requires pointing. The north face is of similar construction but is in better overall condition although some minor pointing is required to the base of the wall. Proposed Works:- Large scale pointing and filling of south face required (possibly sprayed concrete) Minor pointing of north face

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Structure Name: Laxey Breakwater (SN 2245) Location: Laxey Harbour (E4445, N8361) Budget estimate: £100,000

Description: The structural stability of Laxey breakwater has been deteriorating in recent years to the extent that it is now in need of major structural repairs. There is a very large crack running the full height of the breakwater on the inner face that continues through the steps. There are also many other areas of cracking or missing concrete on the inner face and the deck. These combined issues have now become serious enough to consider a full refurbishment and strengthening of the entire breakwater to ensure a catastrophic collapse does not occur. The proposed method of repair is to provide a new 150mm thick reinforced concrete face to the end half of the inner face and around the end of the breakwater that will tie in with the existing sprayed concrete outer face. The steps and deck should also be refurbished at the same time. Proposed Works: Sprayed concrete layer to half of Inner face and end of breakwater Refurbish steps and replace missing concrete Repair cracks in structure with Renderoc LA55

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Structure Name: Alfred Pier (SN 2367) Location: Port St Mary Harbour (E2134, N6737) Budget estimate: Outer face repairs - £15,000 Replacement Deck-

£200,000

Description: The Alfred Pier provides essential protection to Port St Mary harbour including shelter for fishing boats, leisure craft and the RNLI lifeboat. It is in reasonably good condition, but needs some repair works to halt further deterioration. The outer face requires localised concrete patch repairs and repairs to the wave return. The parapet has numerous areas of missing render and needs refurbishing. The deck has cracks along its entire surface but the end third is in the worst condition and is in need of repair. Replacing the deck with a new reinforced concrete slab should be considered in the near future. This work could be phased over 2 – 3 years starting at the end first. Proposed Works:- Phase 1 (Maintenance works) Rake out and fill cracks in face of pier and deck using Rederoc LA55 Repair concrete render using Renderoc LA55 Phase 2 (Improvement works) Replacement deck (approx 2000m2)