Alda bridge reaches key milestone as all piles are drilled

Construction of the Alda bridge across Fossvogur bay has reached a key milestone, with all of its piles now drilled into the seabed, mbl.is reported. The bridge will connect Kársnes in Kópavogur with Nauthólsvík in Reykjavík.

The piles are about 70 centimetres in diameter and are drilled three metres into solid bedrock. The next stage is to concrete the piles, after which dry docks will be lifted onto them and the foundations for the bridge piers will be built inside.

Each foundation has six piles. A dry dock is a giant steel cylinder about the height of a two-storey building, fixed to the six piles. Each measures approximately 6.5 by 15 metres and is eight metres high.

Project manager Guðjón Örn Björnsson said the dry docks are expected to be in place by the end of September, after which work at sea will stop for the winter because of the risk of rough weather. Work will continue on the piers closest to land on both sides, while bridge construction is also progressing in Poland.

“It is difficult to work from a floating barge, as we have been doing, when the sea is rough,” Guðjón said.

The bridge construction has attracted growing attention from passers-by as parts of the structure have begun to rise above the sea. A 55-metre-high crawler crane with a lifting capacity of 300 tonnes will be taken by barge into Fossvogur, with lifting of the dry docks scheduled to begin on August 25.

Guðjón said residents of Kársnes were showing increasing interest in the project, which he described as a significant transport improvement for people in Kópavogur and Reykjavík. Construction teams have used sound meters to monitor noise in the surrounding area. Work in Fossvogur is carried out only at night because of air traffic at Reykjavík Airport, which is open from 7am to 11pm. The team contacts the airport each evening to check for any flights expected after 11pm, including medical flights.

Alda will be 270 metres long and up to 17 metres wide. It is part of the first phase of the City Line project and will be used by City Line vehicles, buses, pedestrians and cyclists, as well as police, ambulance and fire services.