On the section of the Danube just above Budapest, on the Szentendre Island and in the protected areas on the left bank of the river form the northern water resource, which satisfies the larger part, about 70% of Budapest’s water needs. The Szentendre Island is an outstanding water resource complex in terms of both quantity and quality. Quality of the water exploited here equals to the quality of the drinking water, thus it can be directly sent into the network after disinfection, which means it does not require additional treatment.
Water resources of the Szentendre Island produce bank filtered water. The vast majority of the water arrives in the wells after a natural physical and biological filtration process through the sandy-gravelly sediment. River bed gravel allows the water to be cleaned and infiltrate into the aquifer layer and ensures as a transport medium water flow to the production wells.