Cei Balast artificial island, Porthmadog

Cei Balast artificial island, Porthmadog

porthmadog_cei_balast_viewThe island you can see through the gateway here is the most cosmopolitan place in Wales, as it consists of rocks and gravel from around the world! You can see and handle rocks from it at Porthmadog Maritime Museum.

Ships which carried slate from Porthmadog usually returned empty. For stability at sea on their return voyage, they were partially loaded with stone. This load was known as ballast, and comprised whatever rocks, sand, gravel or building rubble were available at the port.

On arrival at Porthmadog, the ships unloaded their ballast. The original dump at the harbour entrance was levelled in 1862 and dumping transferred to a sandy site east of the outflow of the river Glaslyn. The deposits soon built up into an island. Three brothers – Joseph, John and Evan Lewis – built and maintained a quay there for ships to unload.

porthmadog_cei_balast_with_craneThe island is named “Lewis’s Island” on Victorian maps but was commonly known as Cei Balast (Ballast Quay) and marked on a 1901 map as “Ballast Bank”.

The quay ran along the west side and had a steam-powered crane for unloading ships. Ballast was distributed using a tramroad (primitive railway) to the rest of the island. The island had a storehouse and a house for the crane operator – Evan Roberts in the 1890s – and his family. The operation was funded by charges for each vessel unloaded – £3 in the case of a ship named Blodwen in 1899.

In 1877 the owners built a “grid iron” dock at the ballast wharf. Ships rested on the grid so that workers could get underneath at low tide to remove barnacles and other objects (which would impede the ship’s progress at sea).

On this side of the water, the Madog Boat Sales yard occupies former slate wharves, visible on the left in the upper photo which also shows the island and a steam tug towing a sailing ship. The channel between the wharves and island was deep, and outbound sailing ships laden with slate would wait there for a fair wind. The lower photo shows a couple of ships anchored in the channel, with the island’s steam crane on the left.

With thanks to Porthmadog Maritime Museum for the photos

Postcode: LL49 9AY     View Location Map

Website of Porthmadog Maritime Museum

Website of Madog Boat Sales