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SOUTH DUBLIN COUNTY COUNCIL

MEETING OF SOUTH DUBLIN COUNTY COUNCIL

Monday, November 09, 2020

QUESTION NO. 5

QUESTION: Councillor Carly Bailey

To ask the Chief Executive if there are guidelines in place that govern how tree maintenance works are carried out by crews (whether council or private contractors) dealing with trees that have power lines running through them? Currently, trees are been hollowed through the middle or at the side which then allow the tree to continue to grow around the cables. This results in the tree growing unchecked, leading to branches overhanging paths, blocking street lights and becoming dangerously top heavy and unevenly distributed. Trees can become diseased as a result of the breaks to allow cables pass through. They can also become wind-damaged as a result of the hollowing. We have all seen this year that with dangerously top-heavy trees, they are more likely to fall in the storms or in most severe of cases, will have to be cut down all together. Would the Chief Executive agree to look at ensuring crews carry out the most appropriate and necessary maintenance of these trees including that once they get to 'Wire Height' the whole tree should be evenly pruned where ever possible?

REPLY:

The purpose of overhead electricity cable clearance standards for tree pruning is to control or eliminate the hazard and associated risks of timber growing into overhead electricity network in a manner that balances the following requirements,

            -public & staff safety

            -quality of supply standards

            -cost effectiveness

            -current legislation

The main hazards associated with timber growing into electricity network are:-

-Timber providing access to overhead electricity lines. This is a serious hazard where children may climb trees.

-Contact between vegetation and the network that may result in, the vegetation becoming ‘live’, damage to the network or loss of supply to customers

The minimum clearance standard for the low voltage urban network is 1 metre.

The ESB network arrange for contractors to implement this clearance standard. It should also be noted that the Electricity Regulation Act 1993 give authority to utility suppliers to prune trees when required.

The Council as part of its Tree Maintenance Programme includes the inspection and maintenance of trees growing where electricity wires are present. This involves the use of specialised contractors who are trained to work close to the live electricity network. The pruning of such trees are done to ensure public safety and to provide for the best option for the tree. Cutting trees to wire height is not an option in many cases. The council will continue to consult with the ESB on these matters.

The Council's Management Policy - Living with Trees - outlines the principle of planting the ‘right tree in the right place’  which applies to all new and replacement tree planting. Where an overhead wire network is present, the use of smaller trees or alternative locations are identified as options for tree planting.