The loan will help fund about £250m of projects which are part of Welsh Water’s £1.3bn investment program for the period 2010 to 2015.

Some £109m is used for wastewater service improvements to protect the environment and generate renewable energy, and £141m will be spent upgrading water treatment works and renewing water mains to ensure reliable and excellent quality drinking water for customers.

Welsh Water chairman Robert Ayling said that £100m financing will help to fund the company’s ongoing investment that is delivering improving levels of service to its customers while also benefiting the environment of Wales.

Welsh Water is owned by Glas Cymru and has a unique not-for-profit ownership model within the UK water industry, existing solely to provide the best possible service to customers.