Letters on problems with the newly redesigned £21m Postwick Hub on the A47 have been filling our mail sack. Here are some reader views on the junction:

•Public have been let down

So our traffic planners have messed up yet again. Anyone could see from the start that closing the slip road into Thorpe St Andrew was a mistake. Three lanes into two into one will not work. It's £20m wasted. If the design was workable then why did they need temporary traffic lights to test the system? Yet again, we the public, have been let down by those who are hell bent on constructing the NDR come what may.

Jeff Granger, Vera Road, Rackheath.

•Taxpayer to pick up the bill

I'd say that the Postwick Hub fiasco was priceless, except that of course it won't be, and guess who'll be picking up the bill? And this is just the start.

John Knights, Lilian Road, Spixworth.

•Data may have been incorrect

Given that traffic volumes in the Postwick area are much the same as they were prior to the new hub opening and the model presumably predicted much the same traffic flow, we can probably assume that the model has been fed incomplete or inaccurate data. In the computer profession this is known as the GIGO affect — Garbage In Garbage Out.

Council bosses seem to be under the impression that it is the unpredictability of the drivers that is causing the problem, in fact this is the effect and what they need to do is to identify the cause(s). Once they have achieved this they will have a much clearer understanding of the problem and will be in a position to update the model to reflect the current traffic situation. At this stage they should be able to apply 'what if' scenarios to the model to identify a suitable resolution to the problem. I suggest an aerial camera be used to film the hub in the build-up to the rush hour then fast forward the results to identify what is actually causing the problem.

David Shield, Chapel Road, Lingwood.

•Send your letters for publication to eveningnewsletters@archant.co.uk or leave your comments below.