The 22 year-old disappeared almost 17 years ago while walking home from his Christmas Party in Dublin
The Garda Water Unit is now helping in the search for missing Kildare man Trevor Deely.
Officers have been searching an area in West Dublin after receiving a tip off that his remains could be buried there.
Just over three weeks ago - gardai began searching a woodland site here in Chapelizod for what they described as evidence in connection with the disappearance of - Trevor Deely.
So far, only a gun has been recovered but officers havent said whether they believe its connected or not.
The search site is located along the River Liffey and this afternoon members of the garda water unit have been drafted in to help.
Gardai say they will continue to call on specialised units as they are required.
22 year old Trevor Deely from Naas in Co Kildare disappeared almost 17 years ago while walking home from his Christmas Party near Baggot Street in Dublin.
Gardai have described this search in Chapelizod as painstaking in its detail and say theyll continue searching for as long as necessary.