Transitsheds and warehouses of general cargo berths have been analysed as a type of stochastic process. Governning factors in the model are as follows;
i) arrival of cargoes to the transitsheds (or waehouses)
ii) size of loading and unloading for each vessel
iii) pattern of cargoes' stay in the transitsheds.
　The first factor, arrival of cargoes, can be substituted by ships' arrival at the berth. Then, well known Poisson arrival is utilized.
　To the third factor, applicability of negative exponential distribution is confirmed by actual statistics.
　The model thus for mulated is the same of Shot Noise Process in it's mathematical features.
　This model gives us information of variance of storage demand as well as it's mean value. Present method of designning is explained as the special case of the model, designning of mean value, the limitation and deficiency of the present method are also made clear.