To ask the Secretary of State for Environment, Food and Rural Affairs, what steps his Department is taking to ensure (a) Thames Water and (b) other water companies provide (i) accurate and (ii) locally verified assessments of (A) wastewater and (B) drainage capacity for major planning applications.

As set out in Paragraph 7 of the National Planning Policy Framework (NPPF), the purpose of the planning system is to contribute to the achievement of sustainable development, including the provision of homes, commercial development and supporting infrastructure in a sustainable manner.

The Government is clear that housing must come with appropriate infrastructure, including appropriate water infrastructure. Water and wastewater capacity issues are best dealt with at a strategic level through the plan-making process, rather than through individual planning applications. Taking a strategic approach to drainage and wastewater management, will help to identify and mitigate issues related to insufficient network capacity or damaged infrastructure.

A key planning function is to guide development to the most suitable and sustainable locations and to ensure that the associated infrastructure requirements are addressed. Effective co-operation early in the plan-making process is essential. The NPPF makes it clear that local planning authorities should collaborate with each other and with other public bodies, including infrastructure providers, to identify relevant strategic matters to be addressed, including providing for sustainable water supplies.

The Government recognises the importance of having a robust drainage and wastewater system both now and for future demand. Water companies in England are under a statutory duty to provide new water and sewerage connections to residential properties, as well as planning to meet the needs of growth as part of water resource management plans (WRMPs), and drainage and wastewater management plans (DWMPs).

DWMPs set out how a water company intends to improve their drainage and wastewater systems over the next 25 years, accounting for factors including growing population and changing environmental circumstances. These plans will help sewerage companies to fully assess the capacity of the drainage and wastewater network and develop collaborative solutions to current problems and future issues. The plans will bring together various stakeholders including local authorities and industry regulators.