Coasts, Rivers and Ports
Maintaining the UK’s coasts, rivers and ports is a fundamental and growing part of our business. We work with port operators and harbour authorities, the Environment Agency, local councils and private customers on a wide range of marine engineering projects.
Working from the sea or land, our experience comprises comprehensive coastal defence and flood alleviation specialist services including the design, construction and maintenance of seawalls, revetments, rock and timber groynes, beach re-nourishment, cliff and bank stabilisation, harbour and port extensions, scour protection, quays, slipways and jetties.
Our work for the luxury yacht industry includes boat hoists, wet basins and dry docks.
Eastoke Point Coastal Defence
Customer: Havant Borough Council
The works involved the construction of a 650 metre rock revetment, stretching eastwards from midway between the Nutbourne Road and Bosemere Road access points, around Sandy Point nature reserve, to join the existing revetment at Eastoke Point.
In addition the works involved beach management works in raising the level of the beach in front of the new rock structures using over 35,000 tonnes of new imported beach material. Four existing timber groynes have also been replaced with three new rock groynes which are largely buried with beach material. The rock armour was brought in by sea directly to the beach by Stema Shipping who specialise in the handling, transportation and delivery of armour stone for coastal protection work. The works also involved the refurbishment of the concrete splash wall at the back of the promenade including a new surface coating that will significantly extend the walls life. A new access arrangement was also provided to the beach to allow easier access to the promenade throughout the year, particularly in the winter months.
Portland Marina Boat Hoists
Customer: Sunseeker / Dean & Reddyhoff
The contract for two separate clients, Sunseeker International Ltd and Dean & Reddyhoff, was to construct a 320 tonne and 50 tonne boat hoist dock to lift vessels in and out of the water.
The Atkins designed Sunseeker hoist dock incorporated 20, 914mm diameter 17m long tubular piles, 12, 457mm diameter 15m long raking piles, 85 sheet piles and 18, 3.6m precast trough units. Dean & Reddyhoff’s, being smaller, consisted of 8, 914mm diameter piles, 40 sheet piles and 6, 6m precast trough units. The concept of constructing both hoists together as one project using shared resources provided an economical benefit to both clients. The works required several revisions to the programme due to the difficulty of procurement of the specialist piles and the varied pile driving conditions; however the client benefited from the considerable amount of value engineering from Raymond Brown Construction.
Prince Philip Yacht Haven
Customer: Royal Southern Yacht Club
This expansion project for the Royal Southern Yacht Club involved steel sheet piling, quay wall replacements, a new slipway for launching Optimists and other dinghies, a network of ‘walk ashore pontoons’ to provide 70 berths for motor and sailing boats (available at all states of the tides) and dredging works. The works also included the installation of a disabled berth complete with personnel hoist, the first of its kind on the river.
400 sheet piles, varying in length of up to 20m were transported to the site by sea, along with all the necessary piling equipment required as access to the work area via road was restricted. Piles were driven within inches of the existing two-storey Royal Southern Yacht Club which is surrounded by numerous residential properties and businesses. The choice of our piling technique and equipment reflected these difficulties, with regular noise and vibration monitoring carried out during these operations. In addition, 10 tubular piles, also delivered by sea, were installed. The works also required the removal of 1,200m³ of contaminated silts from the seabed which were then remediated on-site and re-used as fill material to raise the level of the Yacht Club’s car park which was then reconstructed and surfaced along with hard and soft landscaping works.
Pendennis Shipyard Wet Basin & Dock
Customer: Pendennis Shipyard
The project, completed four weeks ahead of schedule, comprised the design and construction of a new 7,000m² wet basin/dry dock formed out to sea using 200m of 7m wide sheet piled ‘fingers’, mass filled concrete with pre-cast edge beams and insitu reinforced concrete topping, to include; protection of seagrass and replacement of six chain moorings, creation of a new quay wall, construction of a new entrance structure and a new 13.5m wide travel hoist berth within the basin.
The concrete sill structure was pre-cast onshore and lifted into the water using PSY’s boat hoist. Following installation of the gate, the dock was pumped dry, the basin floor lowered and the third ‘finger’ constructed using traditional shuttering methods to create a 13.5m wide dock to house a 600t boat hoist to lift the 110ft superyachts. Works also included the installation of fenders, mooring bollards, services and surfacing.
Ferry Way Car Park Retaining Wall
Customer: Borough of Poole
Ferry Way Car Park Retaining Wall is located adjacent to the Sandbanks Chain Ferry in Poole, Dorset. The works comprised the construction of a new 40m long sheet piled retaining wall in front of the existing structure. Locally sourced recycled crushed concrete was used to fill the gap between the new and old sheet piles. This was capped off with a new 300mm by 2.5m wide capping slab to tie-in with the existing steps.
Hythe Marina Revetment Repairs
Customer: Marina Developments Ltd
The contract comprised the repairs to existing sections of rock revetment and the replacement of two tidal flap valves. The intertidal mudflats of the Hythe waterfront are part of the Solent and Southampton Water Special Protection Area (SPA) and RAMSAR site. Additional works included the construction of two lines of Gabion baskets which needed removal and replacement as they were nearly non-existent having been eroded away.
M275 Revetment Works
Customer: Enterprise Mouchel
The works, undertaken within the Langstone Harbour SSSI, included the strengthening of the existing sea defences and embankments along the M275 between Hilsea and Portsmouth including the removal and replacement of concrete blocks along the revetment. The project also included the installation of a sheet pile wall, repairs to the embankment earthworks including remedial works to eroded areas, as well as replacement of damaged kerbing where necessary.
Selsey & Wittering Beach Management Scheme
Customer: Chichester District Council
The works comprised beach management schemes in two separate locations in West Sussex which included recycling shingle and raising the planking height of a number of timber groynes, dredging shingle deposition, together with the importation of 7000 tonnes of beach material within a SSSI.
Port of Southampton Fenders Phase 1 & 2
Customer: DP World
Phases 1 & 2 required the installation of 91 no, 7 tonne Trelleborg fenders for DP World in Southampton. Purpose made scaffolds were built for access which could be moved with ease and remain in place, submerged without damage. The fenders were positioned and lifted into place using a Raymond Brown Construction owned 35 tonne Excavator. Each fender was fixed on its own bespoke, individually fabricated backing plate to match the existing piling to ensure that all fenders were parallel to the quayside.
Prior to commencement, a survey was undertaken by our in-house engineering team which was critical to enable confirmation of the exact design specification for each individual painted mounting plate. This information was fed back to the designer, Opus International, who was then able to produce precise fabrication drawings for each plate to ensure there were no issues with the fixing of the fenders to the correct alignment.
Customer: Yarmouth Harbour Commissioners
The Yarmouth Harbour Project comprised the breaking out of concrete capping beams and reducing the height of an existing sheet piled retaining wall and construction of a new sheet piled sea wall with traditional rods and anchors and a reinforced capping beam. Reclamation works were also undertaken using granular fill materials with concrete hardstandings including ducts and drawpits.
Additional works included the construction of a new boat wash-down facility, installation of a new boat lift-out crane and dredging works.
Port of Southampton Scour Protection Works
Berth 101 in Southampton Docks receives the third largest liner in the world, ‘The Independence of the Seas’. When manoeuvring alongside Berth 101, the ship uses bow thrusters which generate a huge amount of turbulence in the water leading to erosion of the seabed adjacent to the quay.
These large scour holes were causing concern about undermining the quay wall and therefore, ABP decided to fill them. The Eastern void in the sea bed was 70m long x 9m wide x 6m deep and the Western cavity measured 60m long x 8m wide x 5m deep requiring a total of 1000m³ of fill.
The design required the use of large sand bags 1.3m x 2.5m when flat, but when filled contained 1m³ (1.7 tonnes) of specific graded sand, supplied by our sister company, Raymond Brown Minerals and Recycling from their Binnegar Quarry in Wareham, Dorset.
Our in-house fabrication team engineered a special hopper to fill the bags which required triple stitching to contain the sand during placement. The bags then had to be placed in a known position without the use of divers, 22m from the top of the existing quay wall.
RNLI Cowes Slipway
This contract was to construct a new slipway adjacent to an existing public slipway providing unrestricted passage for the Lifeboat at all states of the tide. Works included sheet piling around the toe of the existing slipway followed by dredging for the new slipway. 18 tubular steel piles support the galvanised steel runway.
Lifting operations were undertaken using a 50t hydraulic crane operating on a temporary platform founded on the existing public slipway. Design of the temporary works for the crane platform together with the assessment of the slipway strength was undertaken using our in-house design and engineering resources. A set of rails attached to the deck guides a launching and recovery trolley for the Lifeboat.
Seafront Stabilisation & Beach Huts
Customer: Swanage Town Council
Split into two sections, this project involved: replacing buildings and beach huts on the seafront at Shore Road and enlarging a nearby public car park in Broad Road. At Shore Road, the existing toilet block and kiosk were demolished and replaced with larger modern units.
60 new terraced two-tiered beach huts were erected in place of tiered timber buildings. A mixture of pre-cast and in-situ concrete formed the foundations with steel frames and blockwork supporting Purbeck Stone, Evagreen and membrane roofs. The fit-out of the buildings was of high quality and robust to reflect the type and intensity of use anticipated during the busy holiday periods.
The other section of the work comprised the stabilisation of land on the Downs, to hold back the encroachment of soil onto Broad Road Car Park where the number of spaces has diminished over recent years as the land slips worsened. The capacity of the public car park was increased from 167 to 207 spaces by re-profiling the surrounding embankments and optimising bay layout. Ground stabilisation behind the new works formed a major part of the scheme at both sites, using a combination of soil nailing, pre-cast concrete retaining walls and counterfort drains.
Rhiwbina Flood Alleviation Scheme
Customer: Cardiff City Council
This project involved the construction of low level flood walls and culvert installation along the boundaries of residential properties; extensive tree felling and ecological survey work; localised realignment and widening of the watercourse; earth bunds and a large attenuation pond with associated drainage works downstream.
The project also required regular liaison with residents, landowners and the local authority to deliver progress updates and reinstatement plans for residential gardens, church grounds and parkland area.
The project was part-funded by the WEFO and Cardiff City Council that provided flood protection to over 200 homes throughout Rhiwbina.
Construction works were undertaken over seven different work areas stretching over two miles and dealing with over 45 residents, two acres of parks and All Saints Church.
Pines Hotel Cliff Stabilisation
Customer: The Pines Hotel
In October 2015 work commenced to stabilise the cliffs at North Beach below the Pines Hotel, which have been eroding for many years.
The site is adjacent to Swanage beach and involves cliff stabilisation comprising soil nailing, bored pile retaining walls, repairs to existing stability measures, improvements to surface water drainage, sub-surface drainage, a soil-nailed retaining structure, a reinforced soil structure, earthworks and landscaping works.
A first phase of works to stabilise the upper cliff was completed two years ago. This second phase required us to complete the drainage installed in phase one as well as install the drainage for the phase two area. The works also required us to construct a new path and steps leading from the hotel down to the top of the beach hut platform.
Temporary works comprise the construction of a rock and gabion ramp to provide access to the beach together with the construction of a 12m rock and stone wall against the cliff face to act as a platform for the piling plant. Heavy machinery and all vehicle movements along the beach are being made at low tide so they can drive around the end of the timber groynes.
The site was excavated between the piles to act as a platform at sea wall level for the future construction of beach huts. The excavated face, which was contaminated with Japanese Knotweed, was retained with soil nails and a contractor designed stone mattress facing.
A contractor designed reinforced earth wall was constructed using site won material on top of the soil nailed section. Through value engineering the scheme, the contaminated soil was processed on-site and incorporated in the permanent works.
Milford on Sea Beach Huts
Customer: New Forest District Council
The project comprises the construction of 119 new concrete beach huts at Milford on Sea along with associated infrastructure works including a concrete promenade slab, access ramps and steps, pedestrian guard railing, drainage runs, pedestrian surfacing works and beach hut fit out.
The beach huts have been constructed with pre-cast reinforced concrete units to form four individual terraces that extend to 250m in length. Much of the other structural works involved in situ concrete construction, although there was also some structural fill using granular materials and asphalt surfacing.
Commencing in September 2016, enabling works included the demolition of a large area of an existing concrete slab and concrete/blockwork retaining wall as well as some excavation works which used to house the previous beach huts that were damaged by a severe storm in 2014 and ultimately demolished in 2015.
Aside from construction of the beach huts themselves, the scheme seeks to improve pedestrian access and viewing opportunities across the site which includes:
• Pedestrian access on the roofs of the beach hut terraces
• Ramps and steps at the back of the beach huts to allow safe passage throughout
• Widening of the promenade to better facilitate beach hut owners and pedestrians
• Access ramps at either end of the site
• Improvements to the steps in between to enable an at-grade level access along the length of the promenade whilst not impacting on the beach hut owners
• Widening of the gaps between terraces to improve viewing opportunities from behind the beach huts and widening of the steps to the beach
• Decorative guard-railing, hand-railing and doors will be provided
The new beach huts and associated infrastructure provide a much improved leisure amenity to the individual beach hut owners as well as the general public.
Throughout the works, progress was monitored through a camera located on the seafront promenade. The camera is 100% solar powered and uses a 3G data network connection to transmit images.
Southern and South West
M: 07900 210 649
M: 07796 302 158
M: 07855 518 652