underground pipes vs. at-grade horse-drawn carts

[amor de cosmos]

this is a question I saw brought up in an old(ish) book of mine. how much money is saved by transporting water in grade-separated underground pipes vs. carts or trucks that would have to go stoplight to stoplight & share the road with other vehicles? (as it used to be decades ago) & could transporting other stuff in underground pipes also work, such as ground-up garbage?

edit: to put it another way, how much more road traffic would we have now if we didn't move water & other stuff in pipes?

[BTinSF]

In San Francisco, this works well. Of course, it's a little rough on cars, especially at night.


Source: http://farm3.static.flickr.com/2491/...a368448f_b.jpg

[JDRCRASH]

I think it depends. In car-oriented Los Angeles, it would no doubt be cheaper in the long run to transport them underground.

[SHOFEAR]

Your looking at about $250cdn per meter of 300mm pipe. fyi

(including trenching, pipe, installation, backfilling and compacting)