Turbid water processing system and turbid water treatment method

PROBLEM TO BE SOLVED: To provide a turbid water treatment system and turbid water treatment method which can stably treat turbid water resulting from the cleaning of disaster waste, tidal wave sediment and the like.SOLUTION: A turbid water treatment system 200 comprises alkali addition means 214 that adds alkaline material to make first treatment water in a first flocculation reaction tank 202 alkaline, acid addition means 213 that adds acidic material to make second treatment water in a second flocculation reaction tank 205 acidic, first flocculant addition means for adding first flocculant to the first treatment water, second flocculant addition means for adding second flocculant to the second treatment water, turbidity/SS detection means that detects the turbidity or SS concentration of turbid water, and flocculant control means 220 that controls an amount of the first flocculant to be added, on the basis of the turbidity or SS concentration detected by the turbidity/SS detection means.