Levels of Manganese in Raw Water

[tipp79]

I've been asked to find out what the minimum level of Manganese in a Raw Water would lead to the installation of a Manganese Removal Process in a new Build Water Treatment Works.

As 25ug/l is the Utility's Design Target Mn level in final water (95%-ile), would it be fair to assume that a 95%-ile of 25ug/l Dissolved Mn in raw water would necessitate a Manganese removal process (as no dissolved Mn would be removed by a conventional treatment process) or double this in the raw water of Total Manganese i.e.50ug/l.

What in general is considered high Manganese level in a raw water source.

Cheers,

J

 

[bimr]

Manganese is generally removed for aesthetic reasons so there is not limitation for aesthetics. However, manganese at a concentration of 0.2 mg/l may cause encrustations of piping.

A work group in USEPA developed an RfD based on a Greek study of manganism due to drinking water exposure. A lowest oberved adverse effect level of 2 mg/l and a no observed adverse effect level of 0.17 mg/l were identified.

Reference: Water Quality and Treatment AWWA.

 

[GarySCWSVI]

The SMCL for Mn is 0.05 mg/l. My understanding is that a higher levels than that staining will occur.

Gary Schreiber, CWS VI
The Purolite Co.