Underground Pipeline on sectional?

[RipCurl]

I'm not sure this is the right forum for this, but I certainly still consider myself a student... so here goes:

I was looking at my Minneapolis sectional today and noticed that there is an underground pipeline depicted in Canada. It is located near the ND MN border. It heads southeast, but when it hits US soil, it disappears.

1. Why is an underground pipeline shown on an aeronautical nav chart?
2. Why is it shown in Canada, but not in the US?

Thanks

 

[Avenger29]

An underground pipeline is shown b/c the ground above the pipeline is usually kept clear to avoid tree root problems- it produces a distinctive clearing route that can be followed by air. Probably shown on Canadian and not US charts because of regs.

 

[Ralgha]

They show it to make sure you know to miss it when crashing to avoid damaging the pipe.

 

[GravityHater]

They are depicted on us charts too.