It is not possible for any Govt to stop natural calamity occuring and that's the reason its called natural calamity. But Govt could plan to tackle the natural calamity when it occurs. For each city, Govt could identify the possible natural calamities and find action plan to tackle the same. Also they could provide better infrastructure by providing:
a. better drainage system b. have more lakes where water could be stored and used later c. have electricity cables running underground well protected rather than carried through posts d. build shelters/bunkers where public could stay during natural calamity e. form disaster management committee and anounce contact details to public f. conduct mock runs atleast once a year to make public well trained