Carlisle
 

The Carlisle Bridge received the 2004 SAICE (Algoa-Branch) Award for Engineering Excellence. Uhambiso Consult (Pty) Ltd acted as the Lead Consultant on the project and Stefannuti & Bressan Civils (Pty) Ltd as Contractor.


The Works consisted of the rehabilitation and extensions to the Carlisle Bridge on Main Route 42, approximately 40km from Grahamstown. The old roadway carried a single traffic lane of 3m, requiring motorists to approach the bridge with caution and yield to oncoming traffic.


The Carlisle Bridge was originally constructed in 1860 as a steel girder structure and masonry substructure but was washed away by the 1874 floods. The bridge was rebuilt in 1876 but was again destroyed by floods in January 1932. The old concrete arch structure was constructed in 1933, incorporating portions of the old masonry substructure.


The old bridge comprised of two arch spans, each approximately 36m in length. The centre pier is a massive masonry and concrete structure.
The valley of the Great Fish River is subject to high flood levels, which substantially exceeds the existing bridge deck level. The most recent overtopping occurred in 1974.


The Carlisle Bridge structure has considerable historical value, requiring that special techniques and attention be paid to both the design and construction of the widening.


The cost of the construction was just more than R 11 million and the construction was completed in October 2003.