The outer channel of Huanghua port often confronts with sudden siltation induced by strong winds,and the study on the return values of sudden siltation volumes can be helpful to the treatment of sediment accumulation.The point estimations of return values given by diverse methods may produce large differences.The interval estimation can present some reference intervals of design return values under certain confidence levels,so it will provide corresponding instruction for the designers and constructors.Fitting the predicted sequences of the annual maximum sudden siltation of Huanghua port with the lognormal and maximum entropy distributions separately,we estimate the confidence intervals of the return values of sudden siltation volumes by the maximum likelihood method.With the increase of return periods,the scale of the confidence intervals becomes large.The results given by the maximum entropy distribution have higher precision,so they can be applied as reference for the treatment of sediment accumulation.