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| Why not use AGC rules here?
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| *AGC rules apply to right-turns that have a dedicated roadway that is separate from the roadways the AGC connects.
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| *AGC wiki does not address left-turn lanes
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| *The exceptions in the AGC wiki do not address LTL except for a brief old picture that uses ramps in the Signed, Numbered exceptions
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| *All other exceptions use Ramp type roads for any of the left turn options
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| *LTL are not a different roadway than the through road.
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| *The ONLY reason they are mapped for is improved turn instruction timing due to the raised curbs between the lanes, otherwise in appearance they are part of the through road.
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| *Use the same road type of the through road because the LTL is part of the through road not part of the road it connects to.
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| '''Left-turn lane(LTL)'''
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| Left-turn lanes should only be mapped in very limited circumstances-
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| * When there is a raised curb or median between the left turn lane and the through lanes for a long distance before the intersection that the driver might overshoot while waiting for a delayed "turn" audible. In Wisconsin this is called a slotted left-turn lane. This is the main reason to map these in Wisconsin as Wisconsin has built many slotted left-turn lanes.
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| -or-
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| * When the turn lane physically separates from the main road well in advance of the intersection
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| * When the area is "busy" enough that the driver may not get any advance warning that a turn is coming up--in which case a left-turn lane lets you notify the driver a little earlier
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| * When there are user complaints (Update Requests) that the audible was too late, or that the map should have shown a left-turn lane
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| The routing server does not play nice with LTLs and will often create unnecessary right-turn/ U-turn or U-turn/ right-turn fiascos to route through these intersections. Often a junction box is required to help with routing when LTLs are created.
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| Left-turn lanes should be mapped as one-way, using the same road type as the through lanes, with no name, and the speed limit should be set to SL of the segment feeding into the left-turn lane(unless signed otherwise). Essentially these left-turn lanes are the same road as the through road, we are just adding a segment for better turn instruction timing, so they should be mapped using the road type and speed limit of the through road.
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| In general using geometry is sufficient for the desired turn instructions- keep left instruction entering the turn lane and turn left instruction at the turn. When geometry won't work use TIOs for these instructions.
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| Add turn restrictions to prevent U-turn(if applicable), right turn, and to the through-lane left turn(to force use of the left turn lane).
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