Wales: Milford Haven Marina Floating Pontoon Anchors

DAWSON-WAM installed 36nr 406mm dia. tubular steel piles up to 25m in depth, in a major improvement project at the Milford Haven Marina for the Milford Docks Company in Pembrokeshire.

The purpose of the piling was to prevent the natural drift of the floating pontoons and walkways which were previously secured only by anchor chains.

Milford Haven Docks is a natural deep-water harbour which offers a non tidal basin ideally suited to berthing a wide range of vessels.

Pile design by WS Aktins, Swansea, necessitated the maintenance of a 3m socket into bedrock for each pile. Variations in the profile of the bedrock across the basin were compensated for, and differentials in pile lengths allowed the 3m socket to be obtained together with a constant pile height above water level.

Pile installation utilized one of DAWSON-WAM's flexible format TM18/22 piling rigs with its double drive auger gearbox.

Piles were supplied to DAWSON-WAM by the Client to reduce lead in time for materials supply.

Piles were bored into the bedrock using a counter rotating cutting edge provided on the sacrificial tubular piles in conjunction with conventional auger drilling.

Tubular steel piles were fabricated on site by workers from the Milford Haven Docks company, using reclaimed oil industry tube.

Piling operations were conducted from a spud leg floating barge supplied by Williams Shipping and without requiring closure to the Marina which continued to be trafficked by commercial and leisure craft, and provide its docking and mooring facilities throughout.

Piles were completed by internal filling with concrete, ferried across by tug to the piling barge in batches in a floating mixer.

Work was carried out to schedule and with minimum environmental impact, noise and disruption to marina neighbours or users as the pile installation was largely noise and vibration free.