CONGESTION on the M8 is leading to the express bus to Glasgow Airport taking twice as long as it should at peak times.

A report on the plans to scrap the Tram/Train rail link proposal for a Personal Rapid Transit system between the airport and Paisley Gilmour Street analysed the various options for road and rail.

The Transport Minister and the leaders of Glasgow and Renfrewshire Councils decided earlier this year to abandon the plan for a direct rail link and pursue a PRT pod instead.

It noted that the First 500 service from Buchanan Street bus Station to Glasgow Airport via the M8 should take 15 minutes.

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However, the report said that “the service is suffering form journey time variability in both directions on a regular basis and at peak times the doubling of the scheduled 15 minute journey time is not an unusual occurrence.”

The report for the Glasgow City Region City Deal Cabinet noted an exercise carried out comparing 18 airports in Europe including Glasgow with a similar distance to the city centre and a similar number of airport passengers to Glasgow which has around 9 million a year.

It found that Glasgow had more limited surface access that the vast majority of benchmark airports and as such lower share of public transport users getting to and from the airport.

It stated: “Therefore the ability of Glasgow Airport to compete with its competitor airports will be diminished if the public transport offer is not strengthened.”

It compared the costs, likely passenger number s, impact on the road network and impact on the rail network of four options; the direct Tram/Train to Glasgow, the Personal Rapid Transit pods to Paisley, an M8 hard shoulder running bus and a Fastlink bus on non-motorway roads.

The two rail options are similar with Tram/Train costing £138.8m compared to the PRT at £138.4m.

Both bus options are under £50m.

Journey times are also similar with tram train at 18minutes and PRT at 17minutes and the bus considerably longer.

The direct Tram/Train is estimated to see 1.37m passengers a year compared to 1.16m for the PRT pods.

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However it noted that the demands on the rail network between Glasgow and Paisley would increase and it has been difficult to reach agreement that Tram/Train could be accommodated scoring it a moderate negative impact on the current infra structure.

The PRT pod system would not impact on the existing infrastructure as no new trains would be running on the lines.

However, it noted: “The PRT would also require interchange at Paisley Gilmour Street which could be a perceived disincentive to passengers choosing this option.”

But it was stated that the PRT plus rail would still be expected to be more reliable than the bus due to the congestion issues.