COMHAIRLE CONTAE ÁTHA CLIATH THEAS
SOUTH DUBLIN COUNTY COUNCIL

South Dublin County Council Crest

MEETING OF LUCAN / PALMERSTOWN / NORTH CLONDALKIN AREA COMMITTEE

Tuesday, November 23, 2021

QUESTION NO. 23

QUESTION: Councillor Joanna Tuffy

That the Chief Executive Officer will give an update about conservation works for King John's Bridge and what those works entail

REPLY:

Conservation Repair Works at Saint (King) Johns Bridge, a Protected Structure commenced on the 29th September 2021.  Works are being carried out in accordance with the Method Statement provided by the Consultant Conservation Engineer and agreed and approved by the Councils Architectural Conservation Officer.  Remedial and essential repairs and consolidation is required to the bridge structure but the main issue to address was a number of large sycamore tree roots which are penetrating the bridge structure.  Treatment to the roots has been ongoing and has led to the roots decaying in most parts.  Vegetation clearance was completed around the area of the bridge and a trench was dug where the bridge meets the river bank on the Park side to facilitate required archaeological investigation as the Bridge is also a Recorded Monument.

The consultant Archaeologist for the project licenced under National Monuments completed an excavation on the 7the October 2021 of the trench before the removal of roots on the south side of the central bridge arch could be carried out.  The large sycamore root on the Nursing Home side of the bridge is still causing issues and therefore a request was made to Public Realm to treat the root again using Eco plugs and this was completed on the 20th October 2021.  The conservation contractor completed a sample of lime mortar pointing which was approved by the Councils Architectural Conservation Officer to ensure the correct and historic mix was used for repairs.

Localised pointing and repairs using a traditional lime mortar mix to the top of the bridge has been slow due to weather conditions but is nearly complete.  The work being undertaken is minimal intervention and remedial localised repairs in order to prevent any further deterioration of the bridge structure, which has been exacerbated by sycamore roots.  Works were due to be completed by the week commencing 15th November 2021. 

A site meeting took place on the 12th November 2021 with the Consultant Conservation Engineer and the Councils Architectural Conservation Officer to inspect the works to date.  The majority of the work is complete apart from one or two areas of pointing and the insertion of gravel around the base of the bridge.  The contractor will finish these small items and be fully completed by the 22nd November 2021.  Once the conservation repairs are completed by the Architectural Conservation Section, LUPT, the site will remain under the remit of Public Realm as part of Griffeen Valley Park.