Estimations of natural radioactivity levels were carried out for water (surface and groundwater) samples collected from the west bank of the Nile River in Assiut Governorate, Egypt. The activity concentrations in the water samples ranged from 19.20 ± 2.40 to 492.26 ± 71.52 mBq/L, from 15.58 ± 2.62 to 351.39 ± 66.13 mBq/L, and from 50.31 ± 5.58 to 2255.03 ± 249.42 mBq/L for ²²⁶Ra, ²³²Th, and ⁴⁰K, respectively. In this work, the recorded activity concentrations have been organized statistically using a dendrogram cluster and a principal coordinate analysis. In view of the groupings of radionuclide activity, the average annual effective doses through ingestion for adults, children, and infants, despite the responsibility of each explicit radionuclide to the total dose, were assessed and debated. Children had the most important measurement calculations, making them the most regarded mass gathering. All estimations for each different water type, as well as for each individual population group, scored well under the recommended reference value of 0.1 mSv resulting from a one year’s intake of drinking water in accordance with the recommendations of the European Commission (EC) in 1998.