Dublin City Council is playing down the leaks that have been discovered in Dublin Port Tunnel.
Engineers have reportedly expressed concern about the leaks, but the council is insisting they are not a major problem and will be repaired in a matter of days.
Meanwhile, an opinion poll commissioned by the employers' body IBEC has found high levels of support for a tunnel or bridge across Dublin Bay to connect to the M50 and create a full ring-road around the city.
IBEC, which wants the facility build under a public-private partnership, said 74% of local residents questioned as part of the survey supported the idea of a so-called eastern bypass.
It said taxpayers would not be facing huge bills under a pubic-private deal as tolls would recoup most of the cost of the proposed project.
"Most major cities around Europe would have a fully functional orbital route, which helps to distribute traffic," spokesman Reg McCabe said.
"With the Port Tunnel, we now have about 80% of that, so the eastern bypass we would view as being the missing link."