Southern Water launches £1.3bn tender for sustainable drainage and habitat restoration framework

Southern Water Services Limited has issued a formal tender notice inviting suppliers to bid for a new £1.3 billion framework to deliver sustainable drainage and habitat restoration services across its service area in the United Kingdom. The procurement marks one of the largest environmental service tenders published by the water utility to date. It signals an increased focus on nature-based solutions in its forthcoming work programmes.

The tender, designated as the “Sustainable Drainage and Habitat Restoration Framework,” is structured as a multi-lot, multi-year framework, with an estimated duration of around five years. The contract will span from 24 June 2026 to 23 June 2031, allowing Southern Water to appoint a range of providers for services related to sustainable drainage systems (SuDS) and ecological restoration. The framework consists of five distinct lots, each focusing on a different aspect of environmental service delivery:

• Lot 1: Land Management focuses on catchment and nature-based solutions, including land management and pollution control advice, detailed surveys, design, delivery, and optioneering. It also mandates community engagement through outreach and education campaigns aimed at schools and stakeholder groups.
• Lot 2A: Biodiversity Improvement and Biodiversity Net Gain (BNG) covers catchment, green infrastructure, and nature-based solutions aimed at enhancing biodiversity. This lot includes consultancy on BNG metrics and advice, alongside design, delivery, long-term monitoring, and maintenance. Community outreach initiatives form a critical component of this lot.
• Lot 2B: Biodiversity Improvement and BNG involves the purchase of BNG units, providing an additional avenue for suppliers specializing in biodiversity offsetting and trading mechanisms.
• Lot 3: Sustainable Drainage Systems (SuDS) involves providing advice, design, delivery, and optioneering around SuDS and green infrastructure solutions. Like other lots, engagement with the community through educational programmes is integral.
• Lot 4: Habitat Restoration targets both terrestrial and river restoration schemes, covering design, assessment, delivery, ongoing management, and optioneering, complemented by community outreach and education efforts.
• Lot 5: Environmental Monitoring comprises environmental monitoring and modelling activities, including fieldwork, citizen science initiatives, data sharing, analysis, and comprehensive project reporting.

Bidders are expected to demonstrate expertise in civil engineering, hydrology, and ecological enhancement to meet the framework’s broad scope. According to the public procurement notice, suppliers responding to the tender will be expected to support the delivery of comprehensive measures that could include the retrofit or new installation of sustainable drainage solutions and related habitat enhancement works across catchments within Southern Water’s operational area. The framework is designed to enable contracting through successive “call-offs” as specific projects arise during its term.

The tender documents also indicate a formal deadline for bid submissions in early March 2026, with a competitive selection process likely to attract multidisciplinary consortia capable of integrating engineering solutions with long-term ecological management.