There are conflicting ideas on where to take shelter during a tornado. Some say staying in your car is the safest bet.
Some say getting out of your car when a tornado is imminent is a better plan. A culvert, ike this one seems like a good place...for many reasons it isn't.
Although it's a sturdy structure made of concrete this culvert is not a good place to take shelter for several reasons.
First there's a phenomenon known as the "venturi effect." It says winds accelerate when it's squeezed into smaller spaces, so that means severe winds you might see in here will be worse because of this effect.
Another reason, snakes. When water accumulates critters like snakes tend to come out.and getting bit by one would not be a pleasant experience, especially if it's poisonous.
Although a car seems safer in a tornado, actually it's safer to take shelter here if you have to. Odds are higher you could be injured or killed if you're stopped in traffic and a tornado hits.
Finally severe storms not only have tornadoes, lightning and hail. They also produce a lot of rain and that rain can quickly fill up this culvert, increasing the chances of you drowning.
So to re-iterate, taking shelter here is only slightly safer than staying in your car during a severe storm. The best bet is to get as low as possible in a place that won't flood as easily.