What an emergency site must survive
An emergency service website spends most of its life quiet and then has to serve its entire audience in one hour, often on degraded networks, from phones with low battery, by people who are frightened. That is the case it must be designed for — and most such sites are built for the quiet day: heavy pages, no alerting mechanism, guidance scattered across news posts, and no resilience when traffic multiplies.
What we build for an emergency service
First, an extremely light critical path: incident information reachable in one click, minimal weight, readable on a poor connection. Second, alerts by area with subscriptions, so information reaches people rather than waiting to be found. Third, preparedness guidance organised by scenario, written for people who are not calm. Fourth, resilient hosting and caching sized for the peak, because the only load that matters is the one nobody planned.