£20m contract to help unlock housebuilding in large area of Kent

As part of the development of its nutrient mitigation portfolio in Kent, Stour Environmental Credits Ltd (SEC) is seeking to appoint a suitable provider/installer to convert existing septic tanks and private package treatment plants to high efficacy private package treatment plants (PTPs).

The upgrade generates nutrient offset/saving (both phosphorus and nitrogen) from the installation.

The successful bidder (the Services Provider) in this procurement will work with homeowners to upgrade their septic tanks as well as provide SEC with phosphorus and nitrogen offset/saving.

SEC will then convert these nutrient savings into tradeable ‘credits’ to housebuilders and developers who need to offset the additional nutrients arising from the new developments/houses they intend to build in the River Stour catchment area.

The contract term is two years and the estimated contract value is £20m, excluding VAT. SEC will be working with Kent County Council (as the holder of the MHCLG Local Nutrient Mitigation Fund) to secure an initial funding bid to develop this programme.

Companies interested in responding need to act fast – the deadline for the receipt of clarifications about this Invitation To Tender is 10am on 23 June 2025; the deadline to submit tenders is 10am on 30 June 2025.

Anyone interested in learning more can visit the Kent Business Portal.

Stour Environmental Credits Ltd is a Joint Venture company created by Ashford Borough Council and Canterbury City Council. The not-for-profit company is looking to work with mitigation providers and housing developers to enable thousands of much-needed new homes to be delivered across the Stour catchment area, principally in the boroughs of Ashford and Canterbury.

Published: 9 June 2025