ˌʌndɚ ðə wˈɔːɾɚɹ ˈækt nˈaɪntiːnhˈʌndɹɪd ˈeɪɾi nˈaɪn, æz pˈɑːɹt ʌvðə jˌuːkˈeɪ ɡˈʌvɚnmənts pɹˌaɪvəɾəzˈeɪʃən pɹˈoʊɡɹæm fɚðə wˈɔːɾɚɹ ˈɪndʌstɹi, ˌɛndˌʌbəljˌuːˈeɪz ˌɑːpɚɹˈeɪʃənz wɜː tɹænsfˈɜːd tʊ ɐ hˈoʊldɪŋ kˈʌmpəni, nɔːɹθˈʌmbɹiən wˈɔːɾɚ ɡɹˈuːp ˌɛndˌʌbəljˌuːdʒˈiː; ðə wˈɔːɾɚ ænd sˈuːɚɹɪdʒ æktˈɪvᵻɾiz wɜː vˈɛstᵻd ɪn ɐ sʌbsˈɪdjɚɹi kˈʌmpəni, nɔːɹθˈʌmbɹiən wˈɔːɾɚ lˈɪmɪɾᵻd ˌɛndˌʌbəljˌuːˈɛl, wˌaɪl θɹˈiː mˈʌtʃ smˈɔːlɚ sʌbsˈɪdjɚɹiz wɜː sˈɛt ˌʌp tə hˈændəl ˈʌðɚɹ æktˈɪvᵻɾiz, sˈʌtʃ ɐz sˈɑːlɪd ænd lˈɪkwɪd wˈeɪst tɹˈiːtmənt ænd ɛnvˌaɪɹənmˈɛntəl kənsˈʌltənsi.
Under the Water Act 1989, as part of the UK Government's privatisation programme for the water industry, NWA's operations were transferred to a holding company, Northumbrian Water Group (NWG); the water and sewerage activities were vested in a subsidiary company, Northumbrian Water Limited (NWL), while three much smaller subsidiaries were set up to handle other activities, such as solid and liquid waste treatment and environmental consultancy.