I am an economist, amongst other things, and your point deserves an economist's answer!
As is often the case with economics, it is about demand and supply. There is a huge demand from businesses to be located in or near Cambridge because it has one of the top ten universities in the world. The only other place in the UK that offers the same is Oxford. Furthermore, those businesses are just the sort of high productivity businesses that will generate lots of economic growth and the tax income that follows from that.
But in Cambridge supply of three key resources are constrained, these being land, people and water.
With regard to land Cambridge itself is almost full. In prime locations business requirements are now starting to take priority over other uses. This can be seen, for example, in the proposals for business uses on the sites between the railway and Newmarket Road (near to Coldham Lane Jn) and the proposal to move the sewage works near to Cambridge North station.
People can only work in Cambridge if they have somewhere to live and transport infrastructure to get them to and from work. Cambridge has one of the most overheated property markets in the UK because demand exceeds supply. Lots of people who work in Cambridge can't afford to live there. Cambridge is also a city with a very constricted road network that suffers badly from congestion, another example of demand exceeding supply. Buses are not the answer because of the congestion and the overheated labour market, which restricts the supply of drivers.
No, that's what was happening. It isn't happening any more. And the reason for that is water, Cambridge does not have enough of it.
Water was a minority interest until recently, but the 2022 summer changed that, when Cambridge recorded a new maximum temperature of 39.9C and went through nearly all of July and August without any rain. Furthermore, the Cambridge area drainage and river network is very fragile and globally rare: tributaries of the River Cam are about 10% of all of the chalk streams in the world. Demand for water is also affected by the Cambridge area being the UK's most important for agriculture, which takes 10% of water supply, far higher than anywhere else in the UK.
Cambourne and Waterbeach will be the last such developments for a long time. All major proposals for new houses in the Cambridge area are now being blocked by the Environment Agency. That includes a proposal for 3k new houses at Cambourne on the Bourn Aerodrome site. There are more details here:
The Environment Agency objects to thousands of new homes because of "significant risk" of harm.
www.bbc.co.uk
That's why other options need to be looked at.
And this is why, eventually, the options will need to be looked at together. The Cambridge 2040 Delivery Group, set up by Michael Gove and headed by Peter Freeman, will have something to say on that. There's more details on that here:
The city could see huge housing and business growth by 2040 with a new delivery group set up.
www.bbc.co.uk
Michael Gove was in Cambridge recently, where water was the main issue, see here:
The housing secretary says the government wants to give "Cambridge a chance to grow".
www.bbc.co.uk
There is a lot of uncertainty at present, including the following:
- what will be the result of the East West Rail consultation in 2024?
- will the Ely upgrade actually happen?
- what will Peter Freeman's "detailed vision for Cambridge's future" say about housing, transport and water?
- what will happen at the forthcoming General Election?
- who will be Cambridgeshire Mayor in 2025?
- will we get back to inflation below 2%?
A bit of masterly inactivity right now is a good thing. But by 2025 or 2026 many of those uncertainties will have been clarified. I think that looking at the options for March-Wisbech is the right way forward, so that there can be informed decisions in 2025. In an ideal world there would be a similar options study for the Haverhill line, especially now that the existing busway proposal is on hold because of increased costs.