Taita Reservoir - Seismic Strengthening

Taita Reservoir - Seismic Strengthening

Wellington Water
New Zealand
WSP Opus

Key Aspects

Post-tensioning works of watertank
Supply and installation

Taita Reservoir is located in Upper Hutt, Wellington. It is a concrete water tank, 34m in diameter, 104m circumference, and 7.2m high with a dome roof. The whole structure underwent seismic strengthening due to poor overall condition and major leaks. 

Freyssinet were engaged to perform the post-tensioning works of the watertank and were responsible for the supply and installation of:

- 10no. Freyssinet 1x15 external prestressing anchorages

- 1100m of greased and sheathed 15.7mm galvanised strands with 279kN minimum breaking load

- 1100m HDPE duct

Followed with grouting and stressing with monostrand jacks and greasing of all anchorages to provide anticorrosion measures. Prior to installation, all undulations on the surface of the watertank had to be levelled and evened off.