Stream sediment loading and rainfall — a look at the issue

This paper investigates the issue of the nature of the relationship between stream loading and storm intensity and whether stream sediment loading can best be explained by storm intensity (rainfall) or whether a more general average rainfall measure is superior. Based on data covering the years 1947 — 1985 for the Iowa River watershed north of Iowa City, a nonlinear relationship between stream sediment loading and rainfall is indicated. Moreover, average monthly rainfall better explains sediment loading than do other measures of storm (rainfall) intensity. Finally, when the structural stability of the estimated relationships are explored, the indications are that the relationships are stable over the sample period.