I have a farm with dozens of culverts. I never appreciated them until I moved here and had to maintain and replace some of my own. Turns out those simple plastic tubes can cost a thousand dollars or more, and that is before you get to the cost to (re)install them. Infrastructure is expensive.

I learned a lot about culverts after following post 10! ¹

¹ https://www.youtube.com/channel/UCsCNU-ptlze2tqAJSDeVGNQ

First learned of culverts after the 2006 Upstate New York flood wiped out part of I-88

https://www.researchgate.net/figure/Collapse-of-New-York-Sta...