Question to the Department for Business, Energy and Industrial Strategy:

To ask Her Majesty's Government what is their latest assessment of the work being undertaken to upgrade the gas supply network.

In order to ensure the gas network is secure and safe for use, the Health and Safety Executive’s (HSE) enforcement policy for the Iron Mains Risk Reduction Programme (IMRRP) addresses the failure of ‘at risk’ iron gas mains. This involves the replacement of old, corroded iron pipes with polyethylene (plastic) pipes.

Launched in 2002 under Pipelines Safety Regulation (1996), the scheme aims to reduce the risk to consumers of gas leakage incidents from old iron mains. The Programme is also laying the groundwork for the use of the network to potentially carry decarbonised gases such as hydrogen in the future.

The proportion of iron pipes has fallen from 80% of the distribution network in the mid-1970s to around 20% today. This is forecast to fall to around 10% by the end of Ofgem’s forthcoming RIIO (Revenues Incentives Innovation Outputs) price control period (2021-2026) and fall to around 5% by the end of the Iron Mains Risk Reduction Programme in 2032.