Contra Flow

MrDylan · 11-03-2008 2:47pm #1

I see regulary in Dublin three lane road (eg Chapelizard) with the make up for example
Lane 1: Bus lane out of city
Lane 2: Other Traffic out of city
Lane 3: All Traffic into city

All works well at 5pm but at 8am you have two near empty lanes while buses compete with cars on Lane 3.

Seen a couple of overseas solutions to this
1) Use contra flow system and car lanes change direction with overhead traffic lights (but is Irealnd ready for this!)
2) Middle lane is always a bus lane but changes direction at peak times to ensure at peak times bus is always given priority. Use of islands and traffic lights ensure safe areas for people to embark/disembark.

Is some radical thinking needed?

paulm17781 · 11-03-2008 2:54pm

It makes a good deal of sense. I'm sure the DB defenders will be here to tell you DB is perfect and can't improve because whitey keeps holding them down. I think it could work but it would be a bit radical. If you take the bus lane changes direction it would work well as cars shouldn't be in a bus lane anyway.

It's a while since I've been through Chapleizod, are the roads wide enough that the bus lane could have a barrier on either side?

Ham'nd'egger · 11-03-2008 3:21pm

paulm17781 wrote: »

It makes a good deal of sense. I'm sure the DB defenders will be here to tell you DB is perfect and can't improve because whitey keeps holding them down. I think it could work but it would be a bit radical. If you take the bus lane changes direction it would work well as cars shouldn't be in a bus lane anyway.

It's a while since I've been through Chapleizod, are the roads wide enough that the bus lane could have a barrier on either side?

This is an issue for local councils to implement as it is road traffic management. Bus companies would love it as it effectively increases bus lane capacity by double throughout the day; radical as it is, I would like to see it.

antoinolachtnai · 11-03-2008 3:56pm

A bus service greatly benefits from priority in both directions on a bus corridor. The key challenge to increasing capacity is to get buses around to the busy end of the route again after the bus has made a trip. The bus lane on the return leg is important for this.

I don't know if making traffic arrangements more complicated is necessarily the answer. They are already pretty complicated.

Increasing the allocation of road space to particular classes of traffic doesn't in itself improve anything. The critical issue is usually junction capacity.

Victor · 11-03-2008 9:03pm

Usually, you will see the bus lane on the inbound side, so that people needing to get to work / study in the morning get priority.

The evening rush is more spread out than the morning one.

AlekSmart · 12-03-2008 2:02am

Some of the more boring old farts may remember the "Tidal Flow" experiment which ran on the Rock Road some years back.
This entailed the provision of 3 lanes Inbound during morning peak and 3 lanes Outbound in the evening.
At the time I felt it worked quite well,but apparently Dublin City Council (nèe Corporation) had some issues with the methodology which entailed manually setting out long lines of cones to mark the lanes......Too much like work I suppose....so the thing was quietly shelved.

Pigeon Reaper · 12-03-2008 5:34pm

this is commonly done in parts of Germany where overhead electronic signs show the direction of travel. Red X means don't use while a green arrow allows passage in the direction of the arrow. For change over both sides of the signs show the X and normally the lanes only open in heavy traffic. I've never seen an accident resulting from the system while in Germany.

daymobrew · 13-03-2008 1:53pm

AlekSmart wrote: »

Some of the more boring old farts may remember the "Tidal Flow" experiment which ran on the Rock Road some years back.
This entailed the provision of 3 lanes Inbound during morning peak and 3 lanes Outbound in the evening.
At the time I felt it worked quite well,but apparently Dublin City Council (nèe Corporation) had some issues with the methodology which entailed manually setting out long lines of cones to mark the lanes......Too much like work I suppose....so the thing was quietly shelved.

They move the cones (actually more like plastic pegs that stick into the road) on Golden Gate Bridge in San Francisco every day. Maybe 4 lanes inbound in morning (2 outbound) and reverse this for the evening commute.

Contra Flow

Comments