A County council owned smallholding to the north of Hitchin is to be used to off-set the environmental impact of future development in Hertfordshire.

Since February last year (2024) developers have been legally required to provide 10 per cent 'biodiversity net gain' on developed sites – through measures that can include hedgerows, tree-planting and meadow creation.

But where they can't deliver these measures on their own sites they can purchase biodiversity net gain 'units' on alternative sites.

The county council will itself need to use alternative sites for biodiversity net gain sites for the delivery of new schools and waste facilities.

And at the latest meeting of the council's cabinet, it was agreed that part of council-owned Westmill Farm, near Ickleford, could be used for 'biodiversity net gain'.

Westmill Farm site has boundaries with chalk streams and a nature reserve, as well as being on the edge of the Chiltens AONB.

And the scheme has been designed to convert the arable land on the farm into species rich grassland, as well as providing some smaller areas of scrub and woodland creation.

It will, says a report presented to the meeting of the cabinet, create an 'uplift' of 200 'habitat units' across 80 acres – and allow the landscape to be farmed with sheep grazing the grassland.

As part of the plans some of the 'units' at the farm will be available on the open market – or to partners such as care providers, district and borough council's and other social providers.

Presenting the proposal, executive member for the environment Cllr Eric Buckmaster said the the plan was about creating a habitat land-bank – and that the council was "an early adopter – if not the first to do this".

Pointing to the 10 per cent biodiversity net gain requirement, he said it could be for some of the council's own developments or for those developers looking for biodiversity net gain where they can't do it on their own land.

"This Westmill holding fulfils several objectives in our corporate plan," he said.

"There's the ability to create some grassland, have some native sheep breeds – all to do with creating a cleaner, greener environment – and the protection of a nearby chalk stream.

"And it will provide some rental return and an opportunity for a new entrant in our smallholding estate.

"And – as mentioned in addition to this – it will provide potential revenue from the sale of biodiversity net gain units to others who need them."

Executive member for resources and performance Cllr Bob Deering said it was his understanding that this was "a first".

"We are leading the country on this," he said.

And he added: "This is exciting. This is genuinely clever stuff.

"And the way it works is that if a developer somewhere cannot provide the requisite amount of biodiversity net gain on the site he is developing, he can buy from a third party.

"And you and your team have come up with this scheme whereby we can use some of our rural estate to be that third party. It is very smart."

Leader of the council Cllr Richard Roberts said he thought that setting up in advance of a more comprehensive market, was excellent "to stimulate more biodiversity net gain sites across the county."

According to the report presented to the meeting the biodiversity net gain market is "very much in its infancy".

But it suggests that biodiversity net gain units have been known to range between £10,000 for 'low distinctiveness grassland' and £200,000 for 'high distinctiveness woodland'.

The report suggests that the council has a current need for 10.5 units to meet the biodiversity net gain requirements for two new school developments.

And although the council's need is expected to grow the report suggests it would not require the 200 units that Westmill Farm has to offer.