A two way left turn lane is often found in larger towns and cities running down the centre of a multi-lane highway. It is easily identified by the combination of solid and broken yellow lines at both sides and the pair of opposing left pointing arrows painted on the road surface and displayed on black and white regulatory signs overhead.
This lane may be a blessing for those who are turning left in heavy traffic, but it can make life difficult for those who wish to turn left and are entering the highway.
Two way left turn lanes can be handy for turning in the middle of the block. They provide a refuge outside of the usual traffic flow to wait patiently for a gap between oncoming vehicles to turn safely. It also acts to reduce the congestion caused by making left turns by moving turning vehicles out of through traffic.
Learn to Drive Smart mentions these lanes on page 38 and 51. This guide reminds us that when you use one of these lanes vehicles coming from the other direction also use this lane to turn left. It is wise to spend the shortest time and distance in them as is practical to accomplish your turn.
Some jurisdictions limit the distance that you are allowed to drive in a two way left turn lane.
You cannot enter and travel along the two way left turn lane unless you intend to turn left to leave it. Obviously, this means that these lanes must not be used to pass overtaken traffic.
It also means that if you are trying to enter a highway with a two way left turn lane by turning left onto it, you have an extra 3.5 metres or so to go, putting you at risk for a longer distance. You must travel completely across the through lanes that are coming from your left as well as the two way left turn lane before turning left to enter the first lane available for through traffic.
You may choose to enter the enter the centre two-way left turn lane and wait there, perpendicular to it, until there is an appropriate gap in traffic to safely allow you to enter the first available through lane. If you choose to do this, make sure that you do not block any lane other than the two way left turn lane.
Personally, I’m uncomfortable with doing this. If I cannot make the turn without having to stop, I won’t make it. If traffic backs up behind me or the flow of cross traffic makes the turn difficult, it may be a better decision to turn right and go around the block rather than trying to cross all of those lanes to turn left.
It is farther to go, but if you are able to use a cross street with a traffic light this will safely extend your decision time and may remove a number of lanes of cross traffic from your decision making process.
One last thought, and that is the use of signal lights in this situation is mandatory. Tell everyone what your intention is before you do it!