New Bridge East of Butt Bridge.

Having given careful consideration to possible situations for a new bridge East of Butt Bridge, we have come to the conclusion that there are only two practicable proposals:

(i) to place the bridge approximately in line with Cardiff Lane to connect on the North side with Guild Street lying alongside and West of Royal Canal Docks;

(ii) to place it immediately to the East of the Grand Canal Dock, as a continuation of Thorncastle Street, joining on the North side with the quay West of Alexandra Basin.

In regard to (ii): the bridge, being of an opening type, would require opening approximately twice as many times as on site (i); each opening taking some nine minutes would, in our view, cause too much traffic interruption to allow the bridge to be used at all adequately.

From the point of view of long-distance traffic, the site (ii) would necessitate too great a diversion towards the East. Also, this site would necessitate three bridges, two additional to the main bridge, one to continue the quay and the other across the Dodder to connect with the South Circular Road. In these circumstances, we do not consider site (ii) to be suitable.

Site (i) has the following advantages

It will be far enough to the East to alleviate the congestion at Butt Bridge, whereas a bridge any nearer to Butt Bridge would bring the new bridge too near to the Westland Row route.

A glance at the map will show that the approaches exist, together with connections to the North and South Circular Roads.

Some slight adjustments would provide (a) adequate connection between the Docks and industrial areas on either bank of the river, and (b) for through traffic which will use this new route to bypass the centre of the city. This would relieve the Westland Row-Pearse Street congestion. The problem is complicated on the North bank by the roller bridge over the entrance to the Royal Canal Docks. We believe that this can be partly relieved by the limiting of a portion of the quay to one-way traffic and by inducing the traffic from the Oil Refinery site and adjacent area and North Quay extension to use Sheriff Street, with a bridge or sub-way where the level crossing occurs. The approach for the Sheriff Street and Seville Place traffic to the bridge would be along Guild Street adjacent to the Royal Canal Docks. This road should be widened along the Newfoundland Road Housing site and also along the British and Irish yard and Byrne's Hotel. This approach road must be wide enough to admit of queuing up for the opening of the bridge. We understand that the British and Irish berthage and gantries have been arranged for the formation of this bridge as contemplated under the Dublin Port and Docks Board (Bridges) Act, 1929, and also that arrangements have been made for a removal of a length of the sheds along the quays.

In regard to the possibility of achieving continuity of traffic by means of a tunnel, we are of opinion that the length of the approaches necessary to give a proper gradient would be so great that the tunnel would fail to divert the bulk of traffic from the Butt Bridge route, and so defeat the principal object in constructing it. We would point out that the problem here is to lure traffic into a more suitable route and that a tunnel under the Liffey bears no comparison with the Mersey Tunnel where no alternative route exists. Our opinion as to its unsuitability is, therefore, arrived at independently of considerations of its enormous cost.

We, therefore, recommend that site (i) should be selected for the new bridge. We understand that a rise and fall bridge similar to that recently erected over the Tees at Middlesborough is in contemplation. If such a type of bridge is decided upon, we suggest that improvements could, on architectural advice, be made on the Tees type of design. The appearance of this very large structure which will form vast entrance gates to the city, would be of the greatest importance. We, therefore, consider that an architect should be associated with the engineer.