The storm surge is created by wind, waves, and low pressure
There are three mechanisms that contribute to the storm surge:

1. The action of the winds piling up water (typically more than 85% of the surge).

2. Waves pushing water inland faster than it can drain off. This is called wave set-up. Wave set-up is typically 5 – 10% of the surge.

3. The low pressure of a hurricane sucking water higher into the air near the eye (typically 5 – 10% of the surge).

How to survive a storm surge?
People who survived Katrina’s storm surge did one of several things: they floated out an open window, and managed to hang onto debris, a tree, or some other structure above the water, until the surge receded, hours later. Or, they were able to pull themselves into an attic, or make it up to a second floor, where water did not reach, and luckily the home was not swept away. It is common in many flood-prone regions behind levees to keep an axe fastened to the wall of the attic. Then, if water comes in unexpectedly, you can get into the attic and chop a hole through the roof to escape. Don’t forget to keep a length of rope there that you can use to tie yourself to a sturdy part of the house (don’t tie yourself to the steel beams of the house, as these will sink).

The best way to survive a storm surge is to heed evacuation orders and leave before the surge arrives!