EW/FS/WW/AT1
Waste water treatment
Ocean outfalls: Overview
AT1
Different methods exist to dispose of waste effluent originating from human
developments (residential and industrial). The main method is to treat the
effluent to a state that complies with accepted standards so that it can be
discharged into rivers/streams without negatively impacting the environment.
For developments (cities, towns, industries) located on the coastline, an
additional option exists to discharge effluents into the ocean. Depending on the
type of effluent, the sensitivity of the relevant coastline and the degree of dilution
that can be achieved at the ocean discharge location, the effluent may require
different degrees of pre-treatment to comply with the effluent standards
applicable to the particular coastal location.
The treatment of waste water and the discharging of the effluent to the sea is
generally referred to as the “marine treatment” of waste water where the
dynamic oceanographic processes are being utilized to reduce concentrations in
the effluent to the required guidelines for recreation and the natural
environment. The reduction of concentrations is brought about by the initial
dilution of the effluent and the dispersion of the effluent plume when transported
to distant locations.
The typical components of an ocean outfall are illustrated below.
Development:
Residential
Developmen
t: Industrial
Collection
System
Headworks
Main outfall
pipe
Waste
water
Contact: ewisa@wamsys.co.za URL: www.waterinfo.co.za
Prepared by: eWISA
Copyright: All right reserved
Sponsored by:
Diffuser
Diluted
effluent