Discovery of historic slipway on the Strand during flood scheme works

Archaeologists have discovered a historic slipway on the Strand during the Athlone flood scheme alleviation works

Archaeologists have discovered a historic slipway on the Strand during the Athlone flood scheme alleviation works

Groundworks for the construction of a flood defence wall on The Strand, Athlone are being archaeologically monitored by archaeologists from County Clare based consultancy TVAS (Ireland ) Ltd as part of the Athlone Flood Alleviation Scheme undertaken by the OPW in conjunction with Westmeath County Council.

Historic architectural features were discovered on The Strand between Barnett Street and Lloyds Lane in the week commencing May 4. The features are a stone-built slipway and three stone-built retaining walls.

The slipway most likely dates to the Shannon Navigation works of the 1840s and plausibly initially served as an access ramp for works to the drained riverbed.

The slipway and walls are composed of good quality limestone blocks. Most are roughly faced and some are peck dressed. Those on the slipway are worn smooth.

The slipway has a total length of 11.70m and is 2.46m wide (exactly eight feet ). The slipway is parallel to the River Shannon and slopes downward from north to south with a flat base opening to the river at the west.

The retaining walls have been truncated and the surviving depth of the slipway base is 1.75m below the modern ground surface. The northern end of the slipway has been damaged by old ESB cable works.

Stone steps have further damaged the northern part of the slipway. The remainder is in a particularly good condition. Mass concrete was poured onto the western wall when the slipway was decommissioned.

The slipway is not shown on the 1837-8 Ordnance Survey 1st Edition map but is shown on the 25 inch map surveyed 1888 (published 1914 ). The slipway is possibly indicated on the 1952-3 Cassini map.

Photographs of the slipway in the 19th and earlier 20th century show the full height of the retaining walls. A photograph dating to 1946 perhaps shows the slipway with the walls reduced. It is likely then that the slipway was constructed after 1837 and covered over in the mid-20th century.

To allow the construction of the flood defences it is proposed that the previously damaged northern part of the slipway is archaeologically excavated to a depth of 0.8m from the modern surface and for a length of 2.6m. The southern wall will also need to be archaeologically excavated. The later 20th century steps will also be removed.

Preservation in situ of all the undamaged slipway and the flanking east and west walls will be achieved through variation in design utilising a cantilever. A geotextile membrane will be placed over the slipway and walls before concrete for the flood defence wall is poured. Both the elements to be removed and those being preserved in situ will be fully archaeologically recorded (drawn, photographed and described ) prior to any excavation.

The excavation will be licensed by the National Monuments Service and undertaken in the next few weeks by a small team directed by Graham Hull. Mechanical assistance will be required to deconstruct the stonework and concrete. The features will be further photographed and recorded during deconstruction. It is proposed to retain the good quality cut-stone for possible incorporation into the flood defences.

“It was a great and pleasant surprise to discover the slipway and exciting to find it in almost as good a condition as when it was built approximately 180 years ago,” archaeologist, Graham Hull, commented, upon the discovery.

 

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