You may need to identify an ...

You may need to identify an alternate poly/chemical for your flocculation/coagulation step during these high NTU periods - there are several available on the market. What works well is to establish a matrix from jar testing at various NTU levels as a reference as to when to alter the poly dosage and what dosage rates to apply. Then you may need to adjust sedimentation desludge and filter backwash regimes, hopefully the filter units are not compromised as sedimentation should still achieve desired target NTU, we apply <5NTU as sedimentation overflow target.

You may need to contemplate other residuals in the high turbidity water relative to your normal flow NTU levels to ensure no other contaminant increase.

Pre-sedimentation can also be considered, and can be in the form of pre-treatment storage.

Regards