That is the scenario being played out on a busy stretch of Halswell Rd as the carriageway gets a $60 million upgrade.
Heading into the city from the intersection of Dunbars and Halswell roads, some motorists will switch into the left lane to jump the queue building in the right lane.
But a short distance north of the intersection, the left-hand lane becomes a bus lane, forcing drivers to either rely on the traffic in the right lane to let them in or accelerate to reach the merging lanes first.
A Star staffer who uses the road regularly said the behaviour of motorists has been a mixed bag.
“Most let cars merge when they see a right-hand indicator go on, but at times a driver in the right-hand lane will see someone trying to get an advantage by taking the usually empty-ish left lane and get agitated and do their best to stop them from merging,” he said.
“There needs to be some kind of good signage on the BP side of the Dunbars Rd intersection to warn drivers what lies ahead regarding the lanes.
“At the moment there are none at all.”
A Halswell resident who did not want to be named agreed.
He had seen many drivers on Halswell Rd unsure of what to do when they see the bus lane coming up.
“They either plant their boot to get ahead or slam on their brakes to merge into the other lane.”
He said locals know the bus lane is coming up so they merge early.
“And you’ll notice, not a lot of people indicate either.”
He has driven down Halswell Rd many times, and is not a fan of the improvements.
“Very little benefit for the amount of money and time spent.”
The Star observed how drivers are handling the lane design during the morning commute last Friday.
Most drivers heading into the city appeared aware of the upcoming bus lane and switched into the right lane to avoid it.
However, 10 vehicles in the left lane were caught unaware over a 30-minute period.
These drivers either slammed on their brakes and waited for a gap to merge into the right lane or sped up to overtake vehicles on the right. Some did not indicate.
Waka Kotahi NZTA director of regional relationships James Caygill acknowledged the bus lane design is somewhat unique for Christchurch but said it follows best practice.
“In Christchurch, it is typical for bus lanes to be located on the kerbside lane so buses can access the bus stops, although there are exceptions to this,” he said.
“We do appreciate the new road layout may require some adjustment as road users get used to it, and we are monitoring the traffic flows for any issues.”
The bus lanes have ‘bus lane ahead’ and ‘bus lane begins’ signs to signal drivers to merge, as required by roading rules.
Caygill said the signs are a clear indication for drivers to merge.
Bus lanes on Papanui and Lincoln Rds start from the kerbside rather than a regular driving lane, while Manchester St has a design similar to Halswell Rd.
On Papanui Rd and Lincoln Rd, the bus lanes operate only during peak traffic times and function as on-street parking at other times.
