wastewater design report

Bathroom Greywater.

Microbiological: variable levels of thermotolerant coliform, poorer microbial quality
than laundry rinse water.

Chemical: soap, shampoo, hair dyes, toothpaste and cleaning chemicals.

Physical: high in suspended solids, hair and turbidity.

Biological: \ower levels of concentrations of biochemical oxygen demand.

The bathroom (hand basin, shower and bath) generates about 38% of the household
wastewater flow (55% of greywater) and is considered to be the least contaminated
type of greywater. Wastewater from hand basins is more polluted than bath or shower
wastewater. Soap is the most common chemical contaminant found in bathroom
greywater and other common contaminants are hair shampoo, hair dyes, toothpastes
and cleaning chemicals. Biocidal soaps have little effect on reducing the bacterial
load in greywater.

Kitchen Greywater.

Microbiological: variable thermotolerant coliform loads.

Chemical: detergents, cleaning agents.

Physical: food particles, oils, fats, grease turbidity.

Biological: high in biochemical oxygen demand.

Kitchen wastewater is heavily polluted physically with food particles, oils, fats and
other highly polluting waste and is often more polluted than blackwater or raw
sewerage. It readily promotes and supports the growth of microorganisms. Because
of the solid food particles and because fats can solidify, kitchen wastewater may cause
blockages in land application systems unless fats are treated or removed from
greywater.

Swimming Pool and Spa Pool Backwash Water.

Swimming pool backwash water is highly concentrated in microorganisms, chemicals
(such as body oils and cosmetics) and particulates such as powder residue, hair, lint
and pool chemical residues. The amount of backwash water is difficult to estimate
and is variable depending on the size of the pool, filter type and usage patterns.

 

Unearthed Geotechnical P/L. 20 Design Report 022-003