Thread by @SmarterCam

We urge you to respond to the @CambsPboroCA consultation on the #A10 upgrade (Ely to Cambridge) before it closes on Tuesday 14th July:
a10dj.exhibition.app

Here are some thoughts to help you decide how to respond:

In the context of a climate and ecological emergency, building and upgrading roads must be considered as a last resort, when all other options to increase capacity (in terms of moving more people and freight) and improve safety have been exhausted.

There is large potential in getting more people using the railway and cycling. Waterbeach to the Science Park or Stretham to Ely station are both under 4 miles or 20–30 minutes by bike. This needs protected cycleways and better bus connections to railway stations.

Compared with adding lanes to a road, shifting trips from car to walking, cycling, bus and train increases capacity more effectively, at lower cost, lower environmental impact and with significant public health benefits.

Let’s look at the justifications for dualling the A10:

Point 1: “More room for traffic” = More room for traffic to queue.

The capacity of a road is determined by the rate at which vehicles can leave it, not the speed at which they can travel between junctions.

The main constraint for the A10 southbound in the morning peak is the Milton Interchange. Queues on the A10 exist now because the rate of arrivals at the interchange exceeds the rate at which they can enter Cambridge or join the A14.

There is already 280m of two-lane carriageway entering the interchange. That’s more than can clear in a single cycle of the traffic lights. Therefore, extending the dual carriageway will make no difference at all to queuing times.

Similarly, northbound in the evening peak, the constraints are the roundabouts south-west of Ely, where the A10 and A142 share 700m of single-carriageway. Environmental arguments aside, simply adding a northbound lane between the two roundabouts would reduce delays.

Point 2: “creating more space for volume to spread out over peak times”

It’s hard to make any sense of this. If traffic queues in two lanes rather than one, it is less spread out, not more.

Point 3: “allowing for a dedicated cycle path”

The connection is tenuous: dualling a road does not by itself create space for a protected cycleway; rather, it is re-routing where the width is constrained, e.g. through Stretham, that creates the opportunity. However …

The route of a cycleway should be determined by what will make it safe (in reality and perception), direct and attractive. It should not simply be bolted onto a road project for convenience.

Most importantly, the merits of building a cycleway stand on their own. There is never a justification for making investment in cycling dependent on a road scheme.

The £260m the @CambsPboroCA has bid for to dual about 20km of road would buy around 500km of protected cycleway.
cambridgeshire.gov.uk/residents/trav…

Point 4: “Allows for overtaking of slow agricultural and freight traffic”

This does not require end-to-end dualling. Passing lanes and new farm tracks could solve this problem at relatively low cost and environmental impact.

Point 5: “increasing the flow of traffic, and reducing congestion.”

As discussed above, increasing flow into a junction like the Milton Interchange, increases, not decreases, congestion.

Point 6: “Central reservation … decreasing risk of head on collision.”

Whilst this is true, junctions on dual carriageways are typically more hazardous than on single carriageway roads, especially for pedestrians, cyclists and horse riders.

To best way to reduce congestion is to reduce demand to drive at peak times by shifting driver-only car trips to rail, bus, car-share, cycle and home-working. With these options, environmental, social and economic objectives all align, largely avoiding the need for trade-offs.

We believe the priorities now should be:

1) Build protected cycleways linking Cottenham, Histon & Impington, Landbeach, Waterbeach and Milton

2) Build a new cycleway linking Stretham, Little Thetford and Ely railway station

3) Improve bus services connecting Ely, Waterbeach and Cambridge North railway stations with their surroundings. Rail services are already set to increase in capacity (longer trains and station platforms) and frequency as demand increases over the coming decades.

4) Build a bus-only link between Milton Park & Ride and the A14 underpass behind Cambridge Regional College

5) Make localised improvements to the A10 and its junctions to improve safety, reduce conflicts with agricultural traffic and give buses priority over general traffic.

6) For any capacity increases considered, conduct careful analysis of side effects: queue displacement, induced demand, reduced demand for public transport, environmental damage, social isolation of those without access to a car, reduced public health from inactivity, etc.

Please respond to the consultation with as much or as little detail as you have time to provide before it closes on Tuesday 14 July:
surveymonkey.co.uk/r/A10options

Further information about the project may be found here:
cambridgeshirepeterborough-ca.gov.uk/about-us/progr…