Even so, the health of the delta is at the mercy of the cities and industrial centers that spew effluent into the Danube along its 1,770 - mile [2,850 km] journey to the sea.
Delta seisund sõltub paljuski linnadest ja tööstuspiirkondadest, mis reostavad Doonaud selle 2850 kilomeetri pikkuse rännaku ajal mere poole.