New diversions on the M50 have been announced as work begins on "freeflow interchange" for traffic and the Luas Red Line at the Red Cow roundabout.
Announcing the M50 upgrade work programme for the coming months, Hugh Creegan, head of programme management with the National Roads Authority (NRA), said the project is "on schedule and working well".
He asked drivers to keep to the 60km/h speed limit through the N4, N7 and Ballymount interchanges. Speed cameras are in operation along the route.
Traffic layout changes at the Red Cow/N7 interchange will be made in two stages. The first stage takes effect from April 13th, 2007 and the second from April 30th.
Under stage one, N7 westbound traffic exiting the Red Cow interchange will be directed onto a new temporary road through the Luas car park. The existing Luas access will be modified to allow westbound traffic onto Monastery Lane.
Under stage two, a section of the N7 junction roundabout will be removed and traffic from the city turning, north onto the M50, as well as M50 northbound traffic turning right towards the city, will be affected by diversions.
The NRA say that vehicle access to the Luas park and ride facility will be maintained and that the new "Freeflow Slip Road" will be open to traffic in May 2007.
The NRA warns that the works will also affect access to the M50 at the N4. The N4 westbound to M50 southbound freeflow will close later this month for approximately three months.
Also, at the Ballymount interchange two new freeflow slip roads will be opened by the end of May 2007. The new Ballymount bridge will be completed in September 2007.
The NRA also pledged that the current works to create a new traffic lane between N4 and N7, will be completed in May 2007.
"When the work on this section of the M50 is completed in 2008, each side of the motorway between the Ballymount and N4 junctions will have three main lanes and a fourth auxiliary lane between major junctions," said Frank Coffey, director of transportation, South Dublin County Council.
"The interchanges will be upgraded to free-flow or near free-flow, eliminating or minimising the need for traffic lights."
The NRA says it will be 2010 before the entire M50 from the M1 to Sandyford is upgraded, by which time it says there will be three lanes in each direction on M50, an additional fourth lane linking junctions, barrier-free tolling, and no roundabouts nor traffic lights at major junctions.