The government’s plan to build a tunnel under the river Lee in the late 1980s encountered intense opposition from private investors who lobbied for the development of an open-span bridge.
State papers released this week show then taoiseach Charles Haughey and minister for the environment Pádraig Flynn agreed in March 1988 to review the scope for private sector investment in major road projects including the proposed crossing of the Lee which was designed to alleviate traffic congestion in Cork city.
Consultant engineers hired by Cork corporation had first recommended the construction of a two-lane, immersed tube tunnel in 1981 to run between Ringmahon Point and reclaimed land near Dunkettle, about 3km from the city.
They estimated the tunnel would cost £25.2 million and take almost six years to build.
However, a Dublin-based engineering firm, McCarthy and Partners Consultants, claimed in 1989 that the decision to opt for a tunnel had been based on inaccurate data about shipping movements, while a bridge could be built at 25 per cent of the cost of the tunnel.
Paddy McCarthy, owner of the company, claimed a bridge was a “relatively low-cost solution” and would attract private investment that would ensure a construction time of three years.
“In the present economic climate, it is probable that a low-level bridge would predate a tunnel by at least five years and more likely by 10 years,” said McCarthy.
He claimed any disadvantage that a low-level, open-span bridge might have had at the time would become outdated within five years and non-existent within 10 years as more shipping used port facilities at Ringaskiddy instead of the city docks.
The convenience and savings resulting from a bridge would far outweigh any disadvantages of the “random closure” of the bridge to allow vessels pass, he also argued.
In I988, the top civil servant in the Department of An Taoiseach, Pádraig Ó hUigínn, had informed the engineer that the Department of the Environment and Cork corporation noted that there had been no support from any source during a public inquiry held in 1985 for an open-span bridge.
He told McCarthy that the Department of the Environment believed his proposal for a bridge was “unacceptable” for several reasons including the fact that the bridge might need to be opened up to 20 times a day as well as its design being “seriously sub-standard”.
Ó hUigínn said a bridge opening for 20 minutes during peak traffic periods would result in major tailbacks on both sides of the crossing and would “lock” the newly opened roundabout at Dunkettle and its approach roads.
It was pointed out that the bridge was also too close to the bend at Blackrock Castle for navigational reasons and its cost was underestimated by £7.5 million.
The Department of Finance informed Ó hUigínn in May 1988 that the cost of a medium-level opening bridge with associate landscaping “would probably approach the cost of a tunnel” which was estimated to be at £35-38 million at that stage.
Officials in the Department of Finance said the projected traffic volumes would justify starting the scheme in 1994 even if private investment was not available.
The following month, Ó hUigínn noted: “It is clear that the shipping needs are the crucial factor in determining the nature of the crossing.”
The Jack Lynch Tunnel was eventually opened in May 1999 at a cost of £70 million.
- National Archive file reference: 2022/1/422