Mr. Paul Mulvaney:

I thank Deputy Stanley. He has raised a number of different issues and I will try to get to all of them.

First, he mentioned a specific leak and said that a certain amount of fluid went into the canal. However, that fluid did not leak into the canal. There was a leak from a cable near the canal, but the canal banks are impermeable clay structures for keeping water in, and so the only way for fluid to get into the canal is to go in over the top. As that particular cable is 1.2 m below the level of the canal, no fluid from that particular leak got into the canal. Having said that, it was a big leak and it took more time to find than to repair. The repair itself is a tricky piece of work but finding the leaks in these cables can be quite challenging. The traditional method for finding a leak in a cable, which might be a number of kilometres long, is to dig a hole halfway along the cable, bring liquid nitrogen down to freeze the cable, and then monitor the pressure on either side of the frozen piece to see which side the leak is in. That must be done a number of times to find the leak. We have invested in a newer technology where gas is put into the fluid and a detector essentially sniffs that gas out. However, that technology did not work in the case of that leak because it was right under the middle of a very busy road and the old method of digging and looking for the leak took a long time.

The Deputy's last point was about the ESB's spend. We agree work programmes with the regulator on a five-yearly basis when we cover various price reviews and agree a programme of work we are going to get done. Over the last number of price reviews, we have changed out 44 km of that underground fluid-filled cable, which brings the total length of the cable network down to 177 km. We did this using a risk-based method, whereby we replaced the cables with the history of most leaks first. By taking out 20% of the cables, we got rid of 40% of the leaks.