New Goreangab Water Reclamation Plant
(Namibia)
AGENDA
1. Project Background
2. Source Water Characterization, Treatment Process, and
Effluent Water Quality
3. Application and Benefits of Reclaimed Water
4. Regulations
5. Issues and Lessons Learned
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1.
Project Background
Windhoek is a city in South Africa that faces several potable water
supply challenges
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Population: 350,000
Growth rate: 4.05%
1,600 m above sea level
Arid climate (driest country
south of Sahara Desert)
Annual rainfall: 360 mm
Annual Evaporation: 3,400 mm
Droughts occur every 10 years
Closest perennial river: 550 km
away
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The role of water in Windhoek over the years
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1890 to 1933: Groundwater (GW) was the sole source of water
1957: Water supply crisis
○ GW pumping above sustainable yield
○ Over four months, Keddler aquifer dropped 7.4 m out of
52.0 m and Aub aquifer dropped 10.4 m out of 44 m
1960s: Reclamation Pilot Scale was run and proved successful
○ Old Goreangab Water Reclamation Plant ( old GWRP)
built
1968 to 2000: produced from 12% to 18% of total potable water
supply
2002: New Goreangab Water Reclamation Plant built with
capacity increase of 21,000 m3/yr
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2.
Source Water
Characterization,
Treatment Process, and
Effluent Water Quality
Goreangab Dam
Gammams Water Care
Works
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3.
Application and Benefits
of Reclaimed Water
Benefits and Applications of Water Reclamation for Windhoek
Benefits:
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Applications:
Increase capacity to meet water supply
demand
It’s a nearby water supply solution (save
$$)
Alleviates stress from aquifer use
Limits abstraction of natural water
supplies
⬝ Protects ecosystems
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Agriculture
Irrigation of parks and gardens
Potable water!
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4.
Regulations
Water Resources Management Act 11 of 2013:
“To provide for the management, protection,
development, use and conservation of water resources;
to provide for the regulation and monitoring of water
services and to provide for incidental matters”
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Water Resources Management Act 11 of 2013
Aims to…
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Protect, develop and monitor water resources
Requires:
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Application for effluent discharge license
Comply with requirements: including the management of facility
Apply 3 months before expiration
Must have Environment Management Plan
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Water Act of 1956
Aims to…
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improve water quality by reducing pollution and minimizing the
release of harmful chemicals
Must follow water quality standards
⬝ Based on World Health Organization (WHO) drinking water
guidelines
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5.
Issues and Lessons
Learned
Issues the NGWRP has experienced
▫ Distribution
⬝ Leaking from ground into pipes
⬝ Turbidity increases
▫ TDS is slowly increasing
▫ Rise of DBP
▫ Cost
⬝ Don’t charge customers for full recovery
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Lessons Learned
▫ NGWRP is successful
▫ Windhoek should be more transparent with water
quality data
▫ Should take consumer input more into account
▫ Consider expanded reclamation more
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THANK YOU!
Any questions?
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References
Crovello, Stefanie, Joshua Davidson, Amanda Keller. (2010). Perception and Communication of Water Reclamation for the
Sustainable Future of Windhoek. Department of Infrastructure, Water and Technical Services The City of Windhoek.
https://web.wpi.edu/Pubs/E-project/Available/E-project-050510-035057/unrestricted/Windhoek_Water_Report.pdf
DWAF (2006). Technical Summary of Water Accounts. Department of Water Affairs and Forestry. https://unstats.un.org/unsd/
envaccounting/ceea/archive/Water/Namibia_Technical%20Report-Final%20Jan2006.PDF
Kandjeke, Junia Etuna. (2018). Performance Audit Report on Sewerage Infrastructure Management by Local Authorities in
Namibia Within the Ministry of Urban and Rural Development. For the Financial Years: 2013/2014, 2014/2015 &
2015/2016 https://oag.gov.na/documents/86672/304554/2014+-+2016+Sewerage+Infrastructure+Ma
nagement+by+Local+Authorities.pdf/63387403-14a8-dc43-d342-e57cace9ee78
Lafforgue, Michel. (2016). Supplying water to a water-stressed city: Lessons from Windhoek. La Houille Blanche, 4, 40–47.
https://doi.org/10.1051/lhb/2016038
Lange, G.-M. (1998). An approach to sustainable water management in Southern Africa using natural resource accounts: the
experience in Namibia. Ecological Economics, 26(3), 299–311. doi:10.1016/s0921-8009(97)00119-5
Menge, J. (2010). Treatment of wastewater for re-use in the drinking water system of Windhoek. In Water Institute of Southern
Africa Conference: Midrand, Southern Africa.
Republic of Namibia. (2013). Water Resources Management Act 11 of 2013. Republic of Namibia. https://www.lac.org.na/
laws/annoSTAT/Water%20Resources%20Management%20Act%2011%20of%202013.pdf
Van der Merwe, Ben, Piet du Pisani, Juergen Menge, & Eruch König. (2008). Water Reuse - An International Survey of Current
Practice, Issues and Needs - 24 Water reuse in Windhoek, Namibia: 40 years and still the only case of direct water reuse
for human consumption. IWA Publishing. https://app.knovel.com/hotlink/pdf/id:kt00UA7DT7/
Windhoek Goreangab Operating Company. (2022). Sustainable Supply of Drinking Water. Wingoc.
https://www.wingoc.com.na/sustainable-supply-drinking-water
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