Depends what you mean by ‘weather’, but yes, the countryside of Sussex is constantly suffering the attack of rain and the rain either has to soak into the ground where very often it erm dissolves material and eventually finds its way to rivers so that all rivers are carrying material from inland in solution out to the sea, or if erm you get very heavy rain, then the water actually runs off the surface of the ground, and as it runs off it will carry particulate material out into the rivers and then out to sea.