New Zealand’s longest river is a mess of contaminants, RNZ reports. The plan to save it will take 80 years, but can we do better? Nitrogen levels at Tuakau Bridge are in the worst 50% of all monitored river sites. The problems are entrenched, with a 1956 Ministry of Work report showing the river was polluted by sewage and industry contaminants already. Issues were further exacerbated by watered down targets – at one conference, nitrogen targets for parts of the river were changed from 350 mg/m3 to 500 mg/m3.