"Culvert" ... that's a funny little word. My guess is that it's used more in the South than in the North. Call it what you will .... drainage pipe, canal, etc. Whatever your term, these structures almost always hold bass.
In the photo above, the culvert is to the right, underneath the guardrail. Culverts and roadways tend to come in pairs, because these structures facilitate the transfer of water underneath the roadway versus having water pool on the roadway when it rains.
I want to make this very clear ... if the culvert you target is near a road, use common sense. Make sure you are a safe distance from the roadway. Another suggestion would be to make sure there is a guardrail between you and traffic, such as above.
I cast in front of the culvert and directly into it whenever possible. As you can see below, the dividends are mighty.
The bass above was caught using a Berkley Powerbait Power Tube. Pictured below is another culvert bass caught on the same lure.
Tight lines!