England’s 10 Percent Is Fixed. The Boundary Map Is Where the Argument Will Be.

SeaPRwire – From 2 November 2026, a covered development consent application in England has to arrive with an outline biodiversity gain plan and draft requirements, because the national policy objective of at least 10 percent gain now attaches to the date the paperwork is filed.

An application filed on 1 November does not. It stays under the old test for the length of its examination.

That gap of a single day is not a transitional footnote. It is the mechanism the rule runs on. Parliament and Defra put the trigger on the application date rather than on the consent decision, so two schemes with the same footprint, the same habitat and the same local authority can face different evidence burdens depending on when their lawyers queued the file.

For a promoter, the date has become a commercial variable. Filing before the cutover buys an examination under the old test, but it also means defending a scheme against a policy that has already moved. Waiting buys a cleaner policy position and hands over a gain plan, a boundary map and a 30-year management obligation that have to be priced before the application goes in.

The obligation itself sits at the end of the process, in the Secretary of State’s hands. Consent cannot be granted for a new covered order unless the Secretary of State is satisfied that the statutory objective is met. The Examining Authority reads the gain plan during examination and reports; the satisfaction test is applied at the decision, which means an applicant who treats the plan as an annex to be tidied up late is arguing about it in the wrong order.

Scope is narrower than the phrase British infrastructure suggests. The objective reaches specified applications under sections 37 and 104 or 105 of the Planning Act 2008, plus projects directed into the regime under section 35. It covers nationally significant infrastructure in England, including intertidal components out to the mean low-water mark. Marine environment beyond that line is out, and so is anything consented through a hybrid bill.

Data centres get their own instrument. A published biodiversity gain statement applies to data-centre NSIPs, which is not the same population as every server building that goes through ordinary planning permission. A developer who has spent two years on a warehouse-scale scheme under the Town and Country Planning Act does not inherit the NSIP statement by describing the building as a data centre.

The number is the easy part. Ten percent is a floor, applicants use the statutory biodiversity metric, and the rule permits going above it.

The baseline is the hard part, and for data-centre schemes it is defined by disclosure. The baseline takes in habitats inside the order limits that the development will damage plus the areas used to deliver gains. Habitat that is never touched can be left outside the baseline entirely. The boundary map has to separate four things: affected ground, gain areas, retained habitat counted inside the boundary, and unaffected habitat excluded from it.

A developer who draws the boundary tightly reports a small baseline and a modest gain obligation. A developer who draws it broadly, or whose authority insists on a wider one, reports a larger number for the same site. Both can satisfy a 10 percent objective while delivering very different amounts of habitat. That is why the examination will spend its time on the map and the metric inputs rather than on the percentage, which nobody is negotiating.

Delivery has its own constraints. Gains can be delivered on site, through registered off-site habitat, or a mixture of the two. Government credits are described as a last resort, not a routine purchase. Significant on-site gains have to be legally secured and then managed and monitored for at least 30 years, and the data-centre statement goes further, saying habitat should generally be maintained for the remaining life of a longer-running project.

Thirty years of management is a contractual obligation with a cost attached, and it lands on whoever owns the land after the asset is sold. That is a different kind of commitment from a planting schedule attached to a construction programme, and it is the part of the rule most likely to change financing terms more than design choices.

Defra kept the figure at 10 percent after respondents argued for more, and gave alignment with the Town and Country Planning Act regime as the reason. The consistency argument is defensible: a data-centre promoter moving between the two regimes should not face a different percentage depending on which door the project goes through. It also means the NSIP route inherits a number that was set for a different consenting system, with a different evidence culture and a much larger volume of small applications.

Off-site delivery raises a supply question the rule does not answer. A registered habitat bank has to exist, be measured by the same metric and be able to promise management for three decades. Whether that market clears at the volumes the NSIP pipeline implies is the constraint nobody has tested, because until this month no applicant had to buy before filing.

What nobody has tested yet is how authorities will read the inputs. Whether an Examining Authority accepts a narrow order-limits baseline, how it treats habitat that is degraded but inside the boundary, and what condition wording it will accept as legally securing 30 years of management are all open. The first application filed after the cutover will set the working interpretation, and it will do so faster than any guidance note.

For a promoter with a scheme at the pre-application stage, the practical sequence is now fixed. The gain plan is a submission document, not a post-consent deliverable, and the map that defines the baseline has to exist before the application is filed. Anyone who filed in the last week of October has bought themselves an examination under the old test. Anyone filing from 2 November has bought a boundary argument.

The percentage was never going to decide these projects. The map, the baseline and the 30-year management obligation will.