Sir Oliver Letwin is undertaking a review for the Government on “land banking” by property developers. It will seek to “explain the significant gap between housing completions and the amount of land allocated or permissioned and make recommendations for closing the gap”.

The delays are certainly a source of frustration. “Use it, or lose it,” is that great rallying cry – forgetting that planning permission routinely expires after three years under the current rules. In any case if property developers expect prices to be going up why would that be a reason not to build the homes – which they could then delay selling? I suspect delays are more usually caused by the planning system and difficulties raising the required capital.

We will see what Sir Oliver makes of it. But as he knows better than anyone, the worst culprit when it comes to land banking is the state itself – at least based on the broad definition of sitting on surplus land that could be developed. I have quoted from his memoirs, the examples of the Ministry of Defence and Network Rail. Even in London where we are all so squashed, Transport for London owns land equivalent to the size of Camden.

Another prime culprit is the National Health Service. Chris Philp, the Conservative MP for Croydon South, wrote on this site last month that:

“The NHS alone sits on enough surplus land for more than 500,000 homes.”

In his paper for the Centre for Policy Studies, Homes for Everyone, Philp elaborates:

“In its 2017 report on surplus land, NHS Digital identified 1,332 hectares of surplus land across a total of 563 sites. Just 91 hectares of surplus land had been sold previously, with 11 hectares of those sold during 2016/17 – less than 1% of the potential total. At that rate, it would take 112 years to dispose of all the surplus NHS land. (A further 135 hectares is set to be sold by 2020, which is still only ten per cent of the available spare land.) If the NHS was to release its entire 1,332 hectares of surplus land for housing, as many as 533,000 new homes could be created.”

Actually if you look at the data it is likely that the potential is much greater. The NHS Trusts were marking their own homework. They can always say that some bit of unused land isn’t surplus as they might think of something to do with it some time. Then we had 75 of the 236 Trusts that responded denying having any surplus land.

But anyway, the acknowledged 1,332 hectares (that’s 3,291 acres since you ask) is a useful starting point. Surely this is something that councillors should help to pursue? After all, the housing shortage and the financial pressure on the NHS are two of the biggest political concerns of our time – releasing this land for development could help with both.

Perhaps the scrutiny remit of Health and Wellbeing Boards could be extended to cover it. But council leaders should also be chasing the NHS about all these derelict sites. They should be actively encouraged to seek outline planning permission so that the proceeds from sales could be increased. Of course Philip is right that central Government should doing far more. But let’s also get some pressure going locally.