Southern Water has successfully secured an additional £300 million in equity, with new investor Asterion joining Macquarie Asset Management and other existing shareholders. This commitment increases the total equity injection by shareholders to £1.2 billion since July 2025. This funding is crucial for Southern Water to finance its ambitious AMP8 investment program, which totals £6 billion over five years, and to prevent its debt rating from being downgraded to junk status by rating agencies.
The £300 million equity injection was committed by June 2026, building on previous commitments. Macquarie Asset Management had previously committed £245 million by December 2025, taking their total equity injection since 2021 to over £2.5 billion. The overall £1.2 billion package includes an initial £655 million of binding commitments and a further £545 million, with £245 million of that explicitly committed by December 2025 and the additional £300 million by June 2026.
This capital infusion is earmarked for significant infrastructure improvements, including rebuilding five major water treatment plants, upgrading nutrient treatment at 40% of all treatment facilities to enhance river quality, developing new water supply and resilience measures such as a new reservoir and five water recycling plants, and reducing overflows at 170 sites. The investment aims to comply with new legislation and regulatory targets, support population growth, and enhance services for customers, while Southern Water has committed to not paying any dividends before 2030.
