Raw water source

What

Where

When

How

Who

Critical Limit

Corrective action in case critical limit is exceeded

Conductivity

Raw water storage

Daily

Conductivity meter

Water analyst/manager

6.0 - 9.0

Re-assess catchment area

Turbidity

Raw water storage

Daily

Turbidity meter

Water analyst/manager

Not exceeding 5 NTU

Cleaning of the storage tank, Borehole flushing

pH

Raw water storage

Daily

pH meter

Water analyst/manager

6.0 - 9.0

Regulate activities

E. coli

Raw water storage

Monthly

MPN test

Microbiologist/Water analyst

<10

Regulate activities

Sand and Carbon Filter

Turbidity

Filtration outlet

Daily

Turbidity meter

Water analyst/manager

Not exceeding 5 NTU

Backwash

Total dissolved solids

Filtration outlet

Daily

TDS meter

Water analyst/manager

600 mg/l

Backwash

Bacterial count

Filtration outlet

Weekly

Tube method

Microbiologist

10/l

Back wash

Reverse Osmosis

Electrical Conductivity

Treated water Outlet

Daily

Conductivity meter

Water analyst/manager

1000 µ/cm

Membrane flushing

Micro filters

Total dissolved solids

Filtration outlet

Daily

TDS meter

Water analyst/manager

500 mg/l

Change micro filters

UV Steriliser

E. coli

Final treated water

Monthly

MPN test

Microbiologist/Water analyst

<10

Replace the UV light

Bacteria count/100 ml

Final treated water

Monthly

Plate count

Microbiologist/Water analyst

<10

Replace the UV light