Truck roundabout bypass

[US 89]

I was browsing the St. George area on Google Street View today, and came upon something I’d never seen before: a truck bypass of a roundabout at a dumbbell interchange. The off-ramp has flexible bollards blocking the truck bypass, while there’s nothing blocking the one on the on-ramp.

It looks like they were put in sometime between 2011 and 2019, and interestingly only on the northbound side. My guess is they're there because some trucks may not be able to make the tight curve on the roundabout, but any trucks actually using this bypass would be going the wrong way. It could also be an issue with bridge clearance, but this seems unlikely given they're only on the northbound side.

GSVs of off-ramp and on-ramp truck bypasses

[mapman]

I've never seen that before either.  I bet that UDOT added it to allow trucks with tall payloads to bypass the underpass.  The bypass allows trucks to travel from offramp to onramp in the same direction, thus bypassing the bridge.

It also appears that the bypass was added after the initial construction of the roundabouts.  The GSVs on the roundabouts are not all from the same time -- the April 2019 views show the bypass, but the earlier views (such as from 2013) don't.  Maybe a truck hit the bridge (or there was fear that trucks with certain payloads could hit it).

[roadfro]

I've never seen that before either.  I bet that UDOT added it to allow trucks with tall payloads to bypass the underpass.  The bypass allows trucks to travel from offramp to onramp in the same direction, thus bypassing the bridge.

It also appears that the bypass was added after the initial construction of the roundabouts.  The GSVs on the roundabouts are not all from the same time -- the April 2019 views show the bypass, but the earlier views (such as from 2013) don't.  Maybe a truck hit the bridge (or there was fear that trucks with certain payloads could hit it).

This was going to be my guess as well. Interestingly, there's no height clearance warning sign affixed to the overpass in either direction of SR-18.

[Scott5114]

So if someone has a permit, does UDOT send someone out there to pull the bollards, or does the truck just run over them?

[US71]

So if someone has a permit, does UDOT send someone out there to pull the bollards, or does the truck just run over them?

I've heard of something similar before. A truck of sufficient weight supposedly activates a lowering of the bollards.

[Brandon]

So if someone has a permit, does UDOT send someone out there to pull the bollards, or does the truck just run over them?

I've heard of something similar before. A truck of sufficient weight supposedly activates a lowering of the bollards.

These look like they're cemented down.  They're plastic and flexible so I suppose a truck could just go over them easily.  UDOT could also pull the pin at the bottom holding them to their bases.