Transport and Infrastructure

Limerick Tunnel

This PPP scheme consisted of the design, build, finance, operation and maintenance of approximately 10km of dual carriageway incorporating 675m of an immersed tube tunnel under the River Shannon.

The scheme extends from a new interchange at the end of the Phase 1 Limerick southern Relief Road to the N18 Ennis Road and includes 4 no. major grade-separated interchanges. Construction of the scheme commenced in August 2006 and was complete in 2010.

The scheme comprises 10km of hard tolled dual carriageway and a 2.3km single lane carriageway together with associated interchanges and local road alignments and as well as the immersed tube tunnel under the River Shannon, including 43 other major structures and a 750m causeway across Bunlicky Lake. The main toll plaza is on the mainline with a satellite toll plaza on the single lane carriageway line at Clonmacken.

Sisk were contracted to DirectRoute to construct the major structures including the main and ancillary toll plazas, overbridges, underbridges and farm underpasses.

Sisk also provided a considerable amount resource to the Construction Joint Venture in respect of the core management team utilising the particular skills this staff have in marine engineering of this type.

Gidea Park, Essex, UK

Sisk Rail completed the installation of a train carriage wash with associated enabling works for MTR Crossrail at their sidings at Gidea Park, Romford, Essex.

As Network Rail was redesigning the track layout throughout the sidings, the facility was originally installed at a temporary location within the sidings in July 2016. This was on the basis that removal would have to take place 12 months later, either permanently or upon return for re-installation within a new area.

The carriage wash plant was designed to sit on pre-cast concrete bases which could be removed and relocated. A base station was established when the wash plant was first installed, whilst the tanks for water and detergents, along with the pumping chamber, were located at the base station in addition to the plant controls.

New water supply, detergent and drainage ducts were installed between the new location and control station some 350m away and laid within a single 350mm dia. duct.

Lisheen Wind Farm, County Tipperary

Construction of eighteen wind turbine bases, each of 540m³ reinforced concrete single pours, for Vestas V90 Turbines. Four of these bases were constructed within the Bord Na Móna peat bog areas.

The construction of eight kilometres of new access roads as well as crane hard standings, with associated drainage and culvert construction works to accommodate the delivery and erection of the turbine components.

Further scope of works included the installation of 22km of ducting between the turbines, the installation of the earthing cables and the civil works for the substation.

The initial contract programme was 20 weeks with actual completion achieved 24 weeks. An extension of time of five weeks was awarded for additional scope of works of having to make the floating crane hard stands ground bearing due to a new requirement by the turbine suppliers to increase the size of the main crane from a 500t to a 1000t.

Within the contract period Sisk also completed a large earthworks operation for Lisheen Mine by excavating 100,000m³ of quarry fill material and hauling for 3.5 kilometres through the wind farm access roads to facilitate the future decommissioning of the mines tailings pond.

Dawlish Station, UK

Sisk Rail successfully completed the rebuilding of the seaward platform damaged during a huge storm in February 2014. 50% of the structure had been washed away, with the remains left beyond repair.

Our task was to rebuild the riser wall with platform copers on the top, featuring a like-for-like cantilevered timber platform and handrail towards the sea. Challenges included contending with ongoing storms and a tight deadline of ensuring the railway would be open in time for April.

We were also instructed to revamp the station which included new roof cladding, lighting and decorating.

Parkwest Train Station, Dublin

Located within Park West business park on the Dublin-Cork rail line, the project was developed as a joint venture between Harcourt Developments, Dublin City Council and Iarnród Éireann.

The project consisted of the construction of platforms, the main station building and concourse and a plaza. The concourse, measuring 500m² is constructed in structural steel, spanning both the existing Dublin-Cork rail line and the proposed future (KRP) tracks between the main stair cores which are constructed in reinforced concrete.

The steel structure was assembled offline and installed during two track possessions using a 500 tonne mobile crane. The concourse is located approximately 5m above the existing track levels. The concourse roof canopy features a spaceframe structure, providing the most visually striking feature of the station.

The spaceframe roof was fully assembled offline and installed during a single track possession using a 500 tonne mobile crane. The concourse incorporates ticketing and retail facilities, automated ticket vending machines and ticket validation barriers.

Clapham South Underground Station, London

This major refurbishment of this Northern Line Underground Station involved alterations to the ticket hall, lower concourse and platform, as well as the installation of cable and communication systems to cater for improved passenger security and information needs.

As a listed building, the station walls, floor and ceiling finishes were restored to their original condition.

Excavation and construction of two new tunnels was undertaken, 25 metres below street level. These excavations required a temporary shaft, 2.5 metres diameter, to be excavated from street level requiring a major traffic management system.

Working hours were restricted, mainly occurring during the night, hence, keeping noise and dust to a minimum was essential. The quality of the refurbishment has been recognised, by the Ian Allan National Railway Heritage Certificate of Excellence Award.

Whitelee Windfarm, Scotland

This JV project required the design and construction of an extension to the largest onshore wind farm in Europe. Sisk in 50% JV partnership fulfilled the role of Principal contractor for the client and scope included design and construction of the following; 10km of excavated track and 34km of floating roads over deep peat, 68 turbine bases in peat depths of 3.3m, extraction/processing of one million m³ of rock from borrow pits and on site concrete batching of up to 45,000m³.

The access roads were completed in low-strength peat layers to 6m depth and turbine foundations required excavation up to 8.5m depth of peat with on-site water treatment using silt traps, lagoons and rock filtration systems.

The project ground conditions were challenging with the presence of peat layers exhibiting low-strength characteristics. This necessitated foundation excavation to depths of 6m of peat and the construction of floating roads over peat using Brash Matt and Geotextile.

The civil construction programme was completed on schedule in various weather conditions from the deep freeze of 2010, to the heavy Scottish rainfalls, in an environment of deep peat with depths of 6m recorded onsite with the construction team achieving the completion of 1.5 million man-hours on site without a lost time incident.

Shanganagh Wastewater Treatment Plant

The Shanganagh Waste Water Treatment Works (WWTW) was completed as part of the Shanganagh Bray Main Drainage Scheme. The Project required the design and construction of a WWTW at the site of the existing works and the refurbishment of the Bray Pumping Station.

This project also includes the operation and maintenance of the existing and newly constructed Shanganagh WWTW, Bray Pumping Station and Bray Stormwater Storage Tank until 2032.

The plant is considered an essential service and operates on a 24 hour basis. The plant provides pre-treatment, full secondary treatment and drying of sludge while delivering energy recovery through biogas generated as part of the treatment process.

Monarch Hangar, Birmingham Airport

Building on our previous successful hangar delivery at Birmingham Airport, we subsequently completed a design and build contract to provide Monarch Airlines with their new 110,000 ft² hangar.

The steel frame structure has the capacity to accommodate wide-body aircrafts such as the Boeing 777 and Airbus A350. Associated office space was also provided.

Due to the location of the works within the airport, all individuals entering site undertook stringent security clearance procedures, together with receiving a comprehensive health and safety briefing.

These works are part of Monarch’s drive to further enhance their offering within the UK.

Pearse Station, Dublin

ECI M8, Cashel to Mitchelstown

The Cashel to Mitchelstown project, awarded to Sisk and our JV partners is the first Early Contractor Involvement (ECI) scheme in Ireland. ECIs were part of an initiative arising from Sir John Egan’s work on the New Engineering Contract (NEC) to improve contracts and involve contractors earlier in the tendering process.

The scheme comprises the design and construction of approximately 37km of dual carriageway together with various drainage culverts and drainage systems, four interchanges, side roads, link roads and accommodation roads. The structures comprise 19 overbridges, 12 underbridges, six river crossings, seven accommodation bridges, one rail crossing of the Waterford to Limerick line and 34 PCC box culverts.

The earthworks were designed as a balanced cut and fill operation, utilising all the suitable material from major cuttings to form the required embankments throughout the project. The project was a 50:50 joint venture with Roadbridge Ltd.

M58, Sefton, UK

Work started in June 2019 on a multi-million pound M58 improvement scheme in Sefton.

The project involves the construction of the ‘missing’ slip roads at Junction 1 of the busy motorway, providing a northbound off-slip and a southbound on-slip.

As well as improving journey times between Maghull and North Liverpool, it is hoped the scheme will reduce traffic on the A59 and some residential roads and facilitate potential future development in the Maghull area.