Arena Essex Raceway

Our position

Essex Wildlife Trust remains fundamentally opposed to the proposals for the Arena Essex and Fishing Lake, Arterial Road, Purfleet-on-Thames development for a Google data centre campus, owing to serious and irreversible impacts on rare habitats and a nationally important invertebrate assemblage.

In July 2026 the Applicant submitted further documents in response to concerns previously raised by the Trust, by Natural England and by Buglife. These comprised a revised Mitigation Strategy for Broad-leaved Cudweed, a new Assessment of Potential Thames Terrace Gravel Grassland, a Biodiversity Net Gain Strategy identifying Prior's Farm, Fingringhoe as the principal off-site habitat bank, and a Site Assessment setting out the Applicant's case that no reasonable alternative site exists. The Trust has reviewed this material in detail, in co-ordination with Natural England and Buglife. While it provides a more structured evidence base than previous submissions, it does not resolve our fundamental concerns and, in several respects, confirms and reinforces them. Essex Wildlife Trust therefore maintains its objection to this application and urges Thurrock Council to refuse planning permission.

Key points

• The site is a Local Wildlife Site supporting a nationally important assemblage of invertebrates and a legally protected plant, Broad-leaved Cudweed.
• Around half of the Local Wildlife Site would be destroyed, including over 80 per cent of its most valuable brownfield habitat.
• The Applicant's own evidence confirms that its proposed replacement site, at Fingringhoe, is unsuitable to compensate for the loss of the rare gravel grassland found at Arena Essex, and the Trust considers the same reasoning applies to the invertebrate assemblage.
• The Applicant's Biodiversity Net Gain figures, on close examination, fall well short of the level of compensation required.
• The Trust does not consider that the Applicant has demonstrated that no reasonable alternative site exists.

Why this site matters

Arena Essex is a Local Wildlife Site (LoWS), designated for its Open Mosaic Habitat on Previously Developed Land (OMHPDL) — a Priority Habitat comprising bare ground, sandy gravel and low-growing vegetation that has developed over many decades and supports a distinctive range of species.

• The site lies within the Thames Estuary North Important Invertebrate Area (IIA), a nationally recognised network of high-value habitats that has already suffered cumulative brownfield losses exceeding 50 per cent.
• Surveys have recorded a nationally important assemblage of invertebrates at the site, including several Priority Species and Nationally Rare species with very few modern records in Essex.
• The site is one of very few known to support Broad-leaved Cudweed (Filago pyramidata), classified as Endangered and protected under Schedule 8 of the Wildlife and Countryside Act 1981.
• Part of the site also supports Thames Terrace Gravel (TTG) grassland, a habitat that Natural England has identified as unique and of extremely limited national extent.

Concerns with the evidence base

Invertebrate surveys and habitat assessment

• The 2024 invertebrate survey comprised only three visits between May and July, omitting key periods in early spring and late summer, contrary to Natural England's Invertebrate Standard Advice for Essex, which recommends at least six visits across a broader season.
• The survey report omits key information, including weather conditions and a complete species list, and contains references to an unrelated site, undermining confidence in its findings.
• Priority Species recorded in 2018, including the Brown-banded Carder Bee, Phoenix Fly, Five-banded Weevil-wasp and Dingy Skipper, were not detected in 2024, most likely owing to reduced survey effort rather than any genuine decline. Species recorded in 2024 of particular note include a Nationally Rare beetle and two further species with very few modern Essex records.
• The Applicant's habitat assessment relies on novel and unvalidated methodology not recognised by statutory bodies, and inappropriately treats the site's habitat value as a set of independent parcels rather than a single functioning whole.

Thames Terrace Gravel grassland

• The Applicant has, for the first time, acknowledged that the site supports approximately 7.88 hectares of habitat exhibiting potential Thames Terrace Gravel influence, and that its permanent loss requires bespoke compensation. The Trust welcomes this acknowledgement.
• The assessment characterises this resource as a heterogeneous mosaic rather than a uniform habitat, in a manner the Trust considers is used to support an unjustified reduction in the assessed severity of impact.
• Most significantly, the Applicant's own assessment confirms, on Natural England's advice, that the proposed Fingringhoe habitat bank falls outside the recognised Thames Terrace Gravel geography and cannot, by itself, constitute appropriate compensation. The Trust considers this reasoning applies with equal or greater force to the site's wider invertebrate assemblage, which depends on the same substrate, hydrology and microclimate.
• No compensation location, ratio or delivery mechanism has yet been identified; this has been deferred to a post-consent Section 106 process, which the Trust does not consider allows the Council properly to assess the adequacy of mitigation prior to determination.

Broad-leaved Cudweed mitigation

• The Applicant now proposes a five-strand strategy: on-site retention and enhancement, an engineered brown-roof habitat, translocation to Fingringhoe, ex-situ propagation and seed banking, and a 30-year National Conservation Programme.
• The proposed reclassification of the residual effect from Major Adverse to Minor Adverse relies on a mitigation package that has not yet been tested by a completed flowering-season survey; the 2026 survey programme remains incomplete and is not relied upon by the Applicant's own assessment.
• The translocation to Fingringhoe and the engineered brown-roof habitat are both unproven measures, with only a single confirmed translocation receptor site currently identified.
• Funding for the 30-year Conservation Programme is proposed to rest on planning conditions rather than a binding Section 106 legal obligation, which the Trust considers insufficient given the national conservation importance of this population.

Biodiversity Net Gain and the Fingringhoe habitat bank

• The application would result in an on-site net loss of 245.18 biodiversity units, a reduction of 48.99 per cent against the existing baseline.
• The Applicant's Biodiversity Net Gain Strategy presents a gross figure of 617.14 units for the Fingringhoe habitat bank. Of this, only 204.62 units arise from genuinely new habitat creation; the remaining 412.52 units, some 67 per cent of the total, arise from enhancement of habitat that already exists at the site. Once Fingringhoe's own existing baseline of 438.17 units is properly accounted for, the genuine net uplift is 203.94 units.
• This net uplift does not meet the Applicant's own indicative statutory deficit of approximately 295.23 units, before any spatial risk multiplier is applied to reflect Fingringhoe's location in a different planning authority area. The resulting shortfall remains unquantified and unsecured.
• The existing habitats at Fingringhoe — predominantly woodland, wet woodland, neutral grassland, scrub, reedbed and ponds — are ecologically distinct from the open, previously-developed, low-nutrient habitat at Arena Essex that supports its invertebrate assemblage.
• The Trust does, however, consider the proposed habitat management for Nightingale at Fingringhoe to be a comparatively credible element of the wider strategy, since Nightingale is a mobile species capable of colonising newly suitable habitat through natural dispersal, unlike the immobile plant populations and specialist invertebrates that are central to this application.

Alternative sites assessment

• The Applicant's Site Assessment (July 2026) seeks to demonstrate that no reasonable alternative site exists. The Trust has significant reservations about its methodology.
• The Applicant's own screening criteria appear to have been applied inconsistently: alternative sites are discounted for issues such as extending beyond the search catchment, flood zone coverage or Green Belt status, while Arena Essex exhibits comparable characteristics yet is retained.
• Arena Essex, which contains part of a notified Local Wildlife Site and the legally protected Broad-leaved Cudweed population, is recorded as scoring favourably against the Applicant's own ecology criterion, while other sites are discounted substantially for the presence of a nearby, rather than on-site, statutory designation.
• None of the alternative sites was subject to an invertebrate survey, a Pantheon assessment, or a geological or Thames Terrace Gravel assessment comparable to that undertaken for Arena Essex, making a fair comparison impossible.
• The Trust has recommended that the Council seek independent scrutiny of the alternative sites methodology, including from Natural England, before it is relied upon in determination.

What we are asking for

Essex Wildlife Trust considers that this application should be refused. Should the Council nonetheless be minded to approve it, the Trust would wish to see the following secured, as a minimum, through planning conditions and/or planning obligations:

• Compensation sites located in Thurrock, on Thames Terrace Gravels and Open Mosaic Habitat, as close to Arena Essex as possible
• A compensation area of up to twice the hectarage of the lost habitat, to allow for the uncertainty of fully realising proposed habitat creation
• Compensation habitat secured and established in Thurrock before destruction of similar habitat at Arena Essex, allowing time for species to colonise
• In-perpetuity protection of any compensation sites, actively managed by a wildlife conservation organisation with the requisite funding
• A second Broad-leaved Cudweed translocation site identified and secured in Thurrock
• On-site Biodiversity Net Gain secured and monitored for specific threatened species, not solely for habitat types in general

Conclusion

The July 2026 documentation provides a more structured evidence base than previous submissions, but it does not resolve the Trust's fundamental concerns. The Applicant's own evidence confirms, on Natural England's advice, that the Fingringhoe habitat bank is geographically and geologically unsuitable as compensation for the loss of Thames Terrace Gravel Grassland, a conclusion the Trust considers applies with comparable force to the site's wider invertebrate assemblage. The Biodiversity Net Gain Strategy confirms, on its own figures, that Fingringhoe's genuine net uplift does not meet the identified statutory deficit, even before any spatial risk multiplier is applied. Compensation for the loss of Thames Terrace Gravel Grassland, the final Biodiversity Net Gain position, and the protected species licensing strategy for Broad-leaved Cudweed all remain substantively undefined pending post-consent processes. Nor, in the Trust's view, does the Applicant's Site Assessment provide a reliable basis for concluding that no reasonable alternative to Arena Essex exists.

Essex Wildlife Trust considers the application to remain contrary to the National Planning Policy Framework, the NERC Act 2006 biodiversity duty, the Environment Act 2021 biodiversity net gain requirement, and Thurrock Council's own Local Plan policies. The Trust maintains its objection and urges Thurrock Council to refuse permission for this planning application. We remain in close contact with Natural England and Buglife and will continue to update members as the application progresses.