Bridge Street

From Newsletter 16 (February 1998)

Final comments are now invited by the County Council on the Bridge Street closure (see many previous newsletters) before Councillors make their decision on its future in March. The final date for them to receive letters and postcards is 6 February: just after this newsletter reaches you. We still have some postcards left (see Newsletter 15).

At the same time the Council has published a vast amount of monitoring data. These are available at any public library in the City or in South or East Cambridgeshire, and on the World Wide Web (http://www.camcnty.gov.uk). There's so much that it is hard to see the wood for the trees, but here are some salient points. The data are often hard to interpret because they depend on things like the continued general increase in traffic, the vagaries of the weather and so on.

Motor traffic in Bridge Street and Magdalene Street is at a third or so of its previous levels. On the city side of the barrier it is only a sixth. Cycle levels haven't changed much on one table and increased 25% on another, so I don't know what to make of that. Castle Hill is carrying much less traffic.
Silver Street (I mention this particularly because of the letter in Newsletter 15) has seen no change in motor traffic volume. Silver Street also saw a big increase in cycle traffic.
The main motor traffic increase has been on Victoria Avenue and Victoria Road, between 20% and 25% more. The Council apparently expected a higher increase, but some of that expected traffic seems to have gone to Gilbert Road and Elizabeth Way. Chesterton Lane has also seen increases - people from the west going around to the car park, presumably.
I guess because of the increases in Victoria Avenue, some of the cycle traffic from there appears to have transferred to the Midsummer Common river bridges - although the increases there are much bigger than can be accounted for just by this. This also seems to have reduced cyclist casualties in Victoria Avenue. Elizabeth Way saw a reduction in cycle traffic (maybe it rained the day they counted).
Traffic speed in Magdalene Street and Bridge Street actually appears to have fallen slightly, despite subjective perceptions to the contrary. (There are lots of speed measurements for other roads too, some quite outrageous maximum speeds elsewhere - 47 mph in Grange Road for example!)
Madingley Road park and ride increased its use steadily, but with Christmas peaks - it was opened not long before the Bridge Street scheme. Some traffic has perhaps transferred to there from the Cowley Road site.
Pollution levels (in terms of nitrogen dioxide) fell dramatically in Magdalene Street (by 28%), but surprisingly Victoria Road increased by only about 1% and Victoria Avenue was unchanged, despite increased traffic. These are averages, so changes in weather are less influential than for single measurements.
Accidents: because of very small numbers and incomplete figures for this year it's hard to get a complete picture. But it looks as if cycle accidents are down in Bridge Street and Magdalene Street, and the total numbers of accidents are inflated by idiots ramming the barriers, changes to which have steadily reduced such crashes. The City Centre as a whole seems to have seen fewer casualties. Victoria Road and Gilbert Road haven't increased casualties, and as I said, Victoria Avenue saw fewer (1994 was a really bad year here for cyclists for some reason).
Many fewer cars used Park Street car park. Most transferred to other car parks, since first and second quarters saw totals for all the car parks increase on 1996 (third quarter was down slightly). As a result of this and the fact that residents now have to reach the area via Thompson's Lane, traffic in Jesus Lane (and, strangely, Maid's Causeway) has decreased a bit.
There's one weird set of figures: Clarendon Street, a dead end, has seen traffic levels increase hugely - by 60%-70%. What is going on there?

Somehow the Cambridge Evening News interpreted the data to mean the scheme had been 'ineffective'. How did they come to this conclusion? It seems that there is good news in the targeted streets on most fronts. Yes, the scheme has had the expected knock-on effect north of the river, but the consequences in terms of pollution and casualties don't seem to have materialised. I can well imagine they would interpret somewhat longer journey times as bad news (but even on the affected streets, that isn't consistent); to my mind that would have the longer-term effect of deterring motorists and helping park and ride.

All this probably says no more than that both they and I can read what we want into statistics.

Dave Earl