Which of the following is not a direct cause of flooding
melting snow
an ice storm
excess precipitation
excess surface runoff

Melting snow converts a solid into liquid water and flooding. 

Excess precipitation hits the ground and runs off, creating flooding. 

Excess surface runoff, basically the same thing, creates flooding. 

However, an ice storm can simply build UP things like snow. The snow itself is not a direct cause of flooding, so therefore the ice storm is not a direct cause of flooding. 

Answer --> An ice storm