Business challenge
Southern Water is preparing to transition business customers from a flat-rate Surface Water and Highway Drainage charge to a site-area-based charging model, where charges are more closely linked to the size and impermeable surface area of business premises.
Ahead of consultation and implementation, Southern Water needed to understand how businesses would respond to the proposed changes, identify concerns and blockers, test customer-facing communications, and explore appetite for Sustainable Drainage Systems (SuDS) incentives and support.
Our approach
Impact Research delivered a two-phase mixed-method research programme:
The first phase included 100 quantitative interviews with micro, small and medium businesses, supported by cognitive interviews to refine the survey and depth interviews with larger businesses likely to be more affected.
The second phase built on this with 250 respondents, including 150 business customers and 100 households for wider public context. Further cognitive interviews helped ensure the complex charging concepts were clearly understood, while in-depth interviews with large businesses provided deeper insight into the concerns of those most exposed to potential increases.
Outcome
The research found broad support for the proposed changes, with many businesses viewing the site-area-based model as fairer and more environmentally aligned.
It also identified clear priorities for successful implementation: transparent cost breakdowns, clear explanations of revenue neutrality, phased rollout, tailored support by business type, promotion of SuDS incentives, and accessible communications such as leaflets, FAQs and multimedia tools.
The research provided Southern Water with clear insight to guide communications, address customer concerns and support successful engagement ahead of implementation in 2026.