Using Groundwater Options for managing saline wastewater/brine

The document outlines the challenges businesses face when extracting saline groundwater, specifically the production of brine during treatment processes like reverse osmosis. It categorizes brine management into direct discharge and treatment for resource recovery, noting that most solutions are constrained by high capital and operational costs or strict regulatory requirements. Key barriers include a 2019 liquids-to-landfill ban and high costs for sea outfall pipelines and crystallization technologies.

• Groundwater in certain industrial areas of Cape Town is at high risk of salinity, defined as having a conductivity greater than 170 mS/m or a salt concentration exceeding 1200 mg/l. Using reverse osmosis (RO) membranes to treat this water produces a highly concentrated saline wastewater called 'brine'.
• Direct discharge options for brine are limited and often detrimental to the environment or infrastructure. These include discharging into sewers (subject to regulatory requirements), blending with process water to lower salinity, using evaporation ponds (which require significant land, from 100m2 to 4km2), or using sea outfall pipelines, which have high capital costs of approximately R10 million per kilometer.
• Landfill disposal of brine in the City of Cape Town is restricted to the Vissershoek landfill, with costs between R1 500/kl and R2 550/kl. A liquids-to-landfill ban effective August 2019 prohibits wastewater discharge to landfills, though almost-solid brine waste is permitted until 2021.
• Brine treatment technologies for resource recovery are often financially unviable due to high costs. Multi-stage membrane filtration costs R1.5–3 million/MLD per stage, while eutectic freeze and evaporative crystallization have high capital requirements of R80-100 million/MLD and high energy demands of approximately R100-R150/kl of treated brine.
• Because brine management is often too costly or regulatory-constrained, businesses are advised to use saline groundwater in a 'fit-for-purpose' manner (e.g., for cooling or general cleaning) to avoid generating brine, or to partner with other organizations to improve the business case for decentralized treatment.

APA

Fundikwa, B. (2019). Using Groundwater Options for managing saline wastewater/brine. GreenCape. https://greencape.co.za/wp-content/uploads/2022/10/Brine-Industry-Brief-WEB-12-4-2019-3.pdf

Chicago

Fundikwa, Bridget. Using Groundwater Options for managing saline wastewater/brine. GreenCape, 2019. https://greencape.co.za/wp-content/uploads/2022/10/Brine-Industry-Brief-WEB-12-4-2019-3.pdf.

Wikipedia

{{cite report |last1=Fundikwa |first1=Bridget |title=Using Groundwater Options for managing saline wastewater/brine |publisher=GreenCape |date=2019 |url=https://greencape.co.za/wp-content/uploads/2022/10/Brine-Industry-Brief-WEB-12-4-2019-3.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{fundikwa2019using, author = {Fundikwa, Bridget}, title = {{Using Groundwater Options for managing saline wastewater/brine}}, institution = {GreenCape}, year = {2019}, url = {https://greencape.co.za/wp-content/uploads/2022/10/Brine-Industry-Brief-WEB-12-4-2019-3.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }