Alexandra bridges facts for kids
The Alexandra Bridges are two important bridges in Alexandra, New Zealand. They cross the Clutha River (also known as the Mata-au River) right where it meets the Manuherikia River. These bridges help people and vehicles travel across the rivers.
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The Old Alexandra Bridge
Quick facts for kids Alexandra bridge (old) |
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| Characteristics | |
| Design | Suspension |
| History | |
| Opened | 1 June 1882 |
| Closed | 5 July 1958 |
The old Alexandra bridge opened on 1 June 1882. It connected Old Bridge Road on the Bridge Hill side with Rivers Street in Alexandra township. This bridge was a suspension bridge, meaning it hung from strong cables.
It was built by engineer Leslie Duncan Macgeorge. At the time, it was one of New Zealand's largest and strongest bridges. It was very important because the closest bridge upstream had been washed away by a flood four years earlier.
The bridge's road was about 169 meters (554 feet) long from one river bank to the other. Its middle section was about 80 meters (262 feet) long. The center of the bridge stood 12 to 15 meters (40 to 50 feet) above the river.
The eastern side of the bridge had a strong stone base. This base was built on piles made from totara and black pine wood. It was 25 meters (83 feet) long and 8 meters (26 feet) high. The bridge deck had two layers of wooden planks.
On the western side, the main supports and anchors were built on solid rock. The tall piers (towers) reached 27 meters (90 feet) high from the riverbed. The entire structure was held up by eight strong cables, each about 7.6 centimeters (3 inches) thick.
The Alexandra Pipe Band played a special role in the bridge's history. They marched across the bridge during its opening celebrations on 1 June 1882. They also marched across it again on 5 July 1958, to mark its official closing.
What Remains of the Old Bridge?
Today, only parts of the old bridge are left. You can still see the piers (the tall supports), the abutments (the structures that connect the bridge to the land), and the towers. The wooden road and cables were taken away in 1958. These remaining parts are now protected as a Category I historic place by Heritage New Zealand.
The New Alexandra Bridge
| Alexandra bridge (new) | |
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| Characteristics | |
| Design | Steel truss arch |
| History | |
| Opened | 5 July 1958 |
The new Alexandra bridge is located right next to the old one, just a little bit upstream. It is a steel truss arch bridge. This means it uses a strong framework of steel beams to support the road. This bridge is an important part of New Zealand State Highway 8.
The new bridge opened on 5 July 1958. It cost about £261,000 to build. Just like with the old bridge, the Alexandra Pipe Band marched across the new bridge during its opening celebrations. After that, they marched across the old bridge to mark its closing.
The new bridge was built because the old one was only a single lane. This was not enough to handle the growing amount of traffic. The new bridge was designed to be wider and stronger for more vehicles.
Strengthening the New Bridge
Plans were made to make the new bridge even stronger. This work happened between March and June 2015. The New Zealand Transport Agency managed the project, which cost almost $700,000.
Most of the work was done underneath the bridge. Large steel beams were installed to reinforce the structure. These improvements allow heavier vehicles, like trucks, to cross the bridge safely.
