Southern Water customers' water consumption hit a record low in 2015-16 according to figures from its annual report for the year to 31 March 2016.
Southern's two million customers' average consumption doing the year was 130l/day. the national average is 150 l/day. The company said the improvement was the result of its users being better informed.
A spokesman for the firm said metered supply had played a part in reducing consumption. Southern has installed 450,000 meters in households. "Small changes at home have made a big difference. When you’re paying for what you use, this means real, tangible savings,” said Southern's water efficiency manager, Ben Earl.
Southern reported a near 4% decrease in average bills for the report year to which it attributed a 3% fall in revenues to £803.7 m. Lower revenue and increased operating costs including an £8m increase in employee costs from the previous year at £93.1m took operating profit down year on year by 14% at £284.5m.
Fair value losses on derivative financial instruments were reported under revised International Financial Reporting Standards adopted by Southern for the first time. Those losses were down £60m from the previous year (adjusted) boosting reported profits before tax £18m to £128m.