Sanitation and Wastewater Atlas of Africa

Appendix 1. Wastewater streams

Stormwater

Agriculture

Hospitals

Industry

Municipality

Nitrogen, chlorides, copper, zinc, manganese, nickel, cadmium, polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), pathogens, oil and grease. • No treatment. Collect run-off and channel it to the nearest water bodies • Sustainable Drainage Systems (SuDS) approach.

Nutrients, organic matter, pathogens, pesticides, sediments, metals

Pharmaceuticals, personal health-care products and pesticides, organic compounds, ammonia, heavy metals, solids, pathogens

Organic matter, suspended solids, coloured materials, toxic metals, oil and

Pathogens, solids, organic matter, nutrients, heavy metals, salts, micropollutants.

Contaminants

grease, nutrients, micropollutants (dioxins, polychlorinated biphenyls [PCBs]) • Cleaner production as the first treatment step in pollution control. • Centralized treatment plant (and municipal sewage treatment plant in instances when pre- treatment is required). • Waste stabilization ponds • Constructed wetlands (reedbed system) 0.01m 3 /d up to 10,000m 3 /d for constructed wetlands** Employment opportunities, public health and environmental Wastewater reuse for non- potable uses even within the industry; Recovery of by-products, thus minimizing the financial costs associated with treatment and disposal protection through cleaner production; • Presence of government bodies and institutions for industrial effluent treatment and disposal. • Policies and regulations in support of treatment and discharge of industrial effluents are available, but remain poorly enforced. Treated wastewater can be used for some industrial processes, irrigation purposes, groundwater recharge and the production of energy and/or by- products that can be used as raw materials in production processes.

• Best management practices are the first step in the treatment process (e.g. erosion control, nutrient management to reduce excessive application of synthetic fertilizers, integrated pest management which includes biological pest control to reduce reliance on chemical pesticides) • Centralized treatment plant • Constructed wetlands • Anaerobic lagoons

• Pre-treatment (disinfection, chemical, autoclave) • Centralized treatment plants with municipal

• Centralized treatment plant. • Waste stabilization ponds.

Possible treatment: Technology

wastewater, using activated sludge systems.

Variable

362 to 745 litres per occupied bed per day

500 to 450,000 m 3 per day*

Volumes

Financial burden in treatment of polluted water bodies. Flooding can also destroy property.

Employment opportunities, public

Highly pathogenic, no country reported wastewater reuse. Financial burden in treatment and disposal.

Economic opportunity/ burden

Employment opportunities

health and environmental protection through best management practices; Wastewater reuse in irrigation; Financial burden in treatment and disposal

through afforestation programmes; Public health and environmental

protection through wastewater reuse.

• By-laws on sustainable drainage systems in South Africa. • A need to establish the legal frameworks and institutional capacity to charge service fees for storm water management in African countries.

• Presence of government bodies and institutions for wastewater treatment and disposal • Policies in support of controlling excessive use of synthetic pesticides and fertilizers, and excessive water extraction for irrigation need to be developed and implemented.

• Presence of government bodies and institutions for wastewater treatment and disposal. • Policies and regulations in support of treatment and discharge of wastewater are available, but poorly enforced. • Design standards or guidelines for waste stabilization ponds available for North and Southern Africa. Treated wastewater can be used for irrigation purposes and groundwater recharge.

Policy regulations institutional frameworks

Water for groundwater and surface water recharge. Can be used for irrigation purposes.

Treated wastewater can be used for

No documented reuse in African countries, but can potentially provide wastewater for irrigation purposes and groundwater recharge.

Final product (s) can be used for:

irrigation purposes and groundwater recharge. It has the capacity to produce organic fertilizer and reed grass in the constructed wetland.

It has the capacity to produce organic

fertilizer, reed grass in the constructed wetland and energy.

* Resource Recovery fromWaste: Business models for Energy, Nutrient and water in Low- and Middle-income Countries (2018) ** Werner et al., 2001

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SANITATION AND WASTEWATER ATLAS OF AFRICA