Transported from reality

I've been reading the Transport Assessment the Council has commissioned to try to show that their redevelopment plans for Danebury Avenue won't gridlock an already heavily congested area.

The report can be read here as a pdf (and is missing a page).

There are two big problems with this report. First, the "modelling" which they use to forecast how much traffic they think the plans will generate is flawed. And second, the report is incomplete, because while it looks at what the industry calls "modes" of transport - that is car traffic, bus traffic, walking etc individually, it doesn't look at the combined impact.

So for example, you will find nothing in the report about the quality of pedestrian routes around Danebury Avenue when car traffic doubles (as even this report acknowledges); nor the likelihood of road traffic accidents. One of the reasons I oppose this development is that it is simply crazy to direct hundreds of extra vehicles through the heart of the most densely populated, residential parts of the constituency. All the council will do is make Roehampton's shopping area as congested, polluted, unsafe and unpleasant as gridlocked Putney High Street is. The only difference is that Putney High Street is principally a shopping area. Danebury Avenue is principally a residential area.

I mentioned above that the models used to forecast traffic are wrong. As an example of this, it makes the assumption that we all regard supermarket brands in the same way - that someone who prefers Waitrose, for example, will shop at Asda if it is more convenient for them. That isn't my experience, and it wasn't what Roehampton said when I consulted them earlier this Autumn.

This matters, because the Traffic assessment asserts that residents who shop at Asda in Roehampton Vale would cease doing so if, say, a Sainsbury's opens up that is nearer to them. No doubt some will.

But Asda has massive brand loyalty. So do all the major brand supermarkets - it's why they are so big. Brand loyalty trumps convenience in my experience. People won't just change from their supermarket of choice because some other retailer opens up. And whichever retailer does eventually open here will likewise attract outsiders into Roehampton for whom this will be their nearest branch. The traffic assessment dismisses those arguments - and actually goes further, claiming that traffic will DECREASE because Alton residents will stop driving to Asda.

For me, it's a risk too high to believe that anything approaching a majority of the custom of the Danebury Avenue store will come from Asda. I would have had a lot more confidence had the assessment compared like with like: for example comparing the number of people who drive to a store of similar size to that planned for Danebury Avenue (like Putney Sainsbury's) and using those traffic "movements" as the basis.

One final comment. The report forecasts that while traffic down Danebury Avenue will double, in Roehampton Lane it will only increase by 1.3%. That sounds tiny doesn't it? Yet 1.3% (a very conservative estimate of the likely traffic increase, given my comments above) is actually over 400 extra vehicles on Roehampton Lane. I think the true figure will be well over 1,000 extra cars on an already gridlocked road now coming to grips with the 400+ new homes at Queen Mary's Place.

The table below is from the assessment and shows how much traffic already uses Roehampton's roads.