Christchurch is set to overhaul its tsunami warning system, removing 45 sirens and adjusting evacuation boundaries across the city and Banks Peninsula. The changes, part of a broader review of coastal safety, aim to improve response times and public awareness. Local authorities have confirmed the new "blue" evacuation zones will replace the previous system, which relied on audible alarms. The updated plan includes clearer signage and community education initiatives. Officials emphasize the changes reflect the latest scientific data and risk assessments. The transition will take effect in the coming months, with further details to be shared in the next few weeks.