Dublin buses are less reliable than the usual official figures suggest

Agnes Svejda lives near Liffey Valley, works in Blanchardstown, and depends on the W4 bus to get her to work and back.

It often lets her down, Svejda says. She’s put in five reports about it via our No-Show Bus Tracker since January.

The service in the morning is pretty good, but in the evening it’s really pretty unreliable, she said by phone recently. “It’s a bit of a nightmare.”

And when the bus doesn’t come, she has to pick between a long wait, or a €28 taxi fare to get home, Svejda says. “I don’t want to get a car.”

So when Svejda hears that official National Transport Authority (NTA) stats show reliability of about 98 percent for Go Ahead Ireland, which operates the W4 and some other routes, and Dublin Bus, which operates most routes in Dublin, she is sceptical.

“Getting to work, maybe 90 percent, but coming home more like 75 percent,” she says.

Svejda is right to be sceptical. The most recent reliability reports from the National Transport Authority (NTA) do indeed show the companies’ official reliability was about 98 percent – something Dublin Bus has pointed to publicly.

But there’s a gap between those official (or “contractual”) reliability figures and the bus operators’ actual reliability – how often their buses actually showed up at bus stops to pick up passengers.

In percentage terms, the gap is small: actual reliability appears to be about 96 percent for Go Ahead and 95 percent for Dublin Bus in the fourth quarter of 2024, according to figures from the NTA.

But those few percentage points represent hundreds of thousands of kilometres of bus routes that were planned but not operated – for reasons the NTA judged to be out of the control of bus operators.

This means these “lost kilometres” did not count against the company’s official reliability, or result in a financial penalty, even though they meant wannabe passengers were left standing on the side of the road, bus-less.

It also means that a major reason behind missing buses perhaps has been under-examined in public debate: traffic congestion.

Kilometres lost, and reasons why

The NTA oversees the bus system and contracts Dublin Bus and Go Ahead Ireland to operate the buses along the routes.

They have to hit at least 98 percent reliability, or they face financial penalties – which can reach into the millions of euro.

For this purpose, reliability is calculated in terms of “lost kilometres”. That is, total scheduled services minus total operated services.

Reports from the NTA on the reasons Go Ahead and Dublin Bus did not operate scheduled services in the fourth quarter of last year, show a variety of reasons.

Of about 3 million kilometres Go Ahead was scheduled to operate, there were about 135,300km it didn’t operate, an NTA report shows.

Of these, 73,700km were “deductible”, reducing its official reliability. The two biggest reasons by far, together accounting for 69 percent of deductible lost kilometres, were “no serviceable bus”, or “absence/late/sickness”.

For Go Ahead Ireland and Dublin Bus, challenges hiring and retaining staff – including drivers and mechanics – has long been a reason given for problems providing reliable bus services in the city.

Aside from those “deductible” lost kilometres, for Go Ahead, there were also another 61,100km that were not deductible, meaning they didn’t reduce the company’s official reliability or lead to penalties, but the bus didn’t show up for passengers.

The single biggest reason by far, accounting for 89 percent of these non-deductible lost kilometres, was “abnormal congestion”. Traffic.

When a bus gets behind schedule and because of traffic congestion, one strategy the operators use is to skip some or all of the rest of the stops on the route to get back on time.

For Dublin Bus, of about 15.6 million kilometres it was scheduled to operate in the fourth quarter of last year, there were about 756,200km it didn’t operate, an NTA report says.

The biggest reason, accounting for 66 percent of Dublin Bus’s deductible lost kilometres? “Shortage of establishment”, which means a staff shortage, an NTA spokesperson said.

When it comes to the about 425,400 non-deductible lost kilometres that didn’t count against Dublin Bus’s official reliability, or result in penalties, but that represent buses not serving customers, there was also one big reason.

More than 83 percent of those non-deductible lost kilometres were due to “Abnormal traffic congestion/blocked road due to traffic accident/ breakdown of another vehicle”, the NTA report says.

The gap between official and actual reliability for Dublin Bus widened towards the end of last year, according to an NTA chart.

This happens towards the end of each year actually, says Jeremy Ryan, the NTA’s director of public transport services.

“This is associated with increased use of non-deductible lost-km cause codes by operators  at this time of year,” Ryan said.

“This is due in large part to out of the ordinary traffic congestion issues that arise in the lead up to Christmas, but may also be due to severe weather events resulting in service cancellations or diversions, which are more likely at this time of the year,” he said.

A better way?

In February, Dublin Bus’s chief of service operations Gwen Morgan, published a post on her LinkedIn titled “The War on the Ghost Bus”.

“If you’ve ever waited for a bus that didn’t turn up, you know the frustration of the so-called ‘Ghost Bus’,” she wrote. “For Dublin Bus, it’s a challenge we’ve taken head-on. Over the past year, we have waged a relentless campaign to improve performance.”

After much effort, Dublin Bus’s “overall service reliability” was 98 percent, Morgan wrote.

Why did Dublin Bus, when communicating with the public, use the official/contractual reliability figure and not the actual figure? Dublin Bus has not responded to a query on this sent Monday evening.