ˌɛndʒɪnˈɪɹz ˈɛstᵻmət ˌʌnɪmpˈɛɹd ɔːɹ nˈætʃɚɹəl ɹˈʌnɔf baɪ ˈɛstᵻmˌeɪɾɪŋ ˈɔːl ʌvðɪ ɪfˈɛkts ʌv hjˈuːmən "ɪmpˈɛɹmənts" tə flˈoʊ ænd ðˈɛn ɹᵻmˈuːvɪŋ ðiːz ɪfˈɛkts.
Engineers estimate unimpaired or natural runoff by estimating all of the effects of human "impairments" to flow and then removing these effects.