WHY IS WATER STORAGE IN IMPORTANT? 

Many people lack access to clean drinking water – targeted water storage is the key to solving this challenge. 

• Bridging seasonal dry periods : Rainfall occurs only 3–6 months per year. Without storage, rainwater is lost while acute shortages persist during the dry season. 

• Mitigating climate change : The IPCC projects 10–20 % less rainfall by 2050 for exemple for Sub-Saharan Africa. Climate-resilient storage infrastructure secures the future of entire regions. 

• Independence from central infrastructure : 75 % of households have no water connection, electrification rates are below 20 %. Decentralised storage solutions operate autonomously – without power grids or pipeline networks. 

• Improving health : Over 300,000 children under 5 die annually from diarrhoeal diseases caused by unsafe water. Clean storage combined with treatment drastically reduces waterborne diseases. 

• Enabling economic development : Women and girls spend hours each day collecting water. The World Bank estimates a GDP loss of 10–15 % by 2050 without improvement. 

• Strengthening communities : Community projects such as sand dams and berkads foster cooperation. Construction using local materials and labour strengthens the local economy. 

WHAT COST-EFFECTIVE STORAGE SOLUTIONS CAN WE DELIVER ? 

For every region and every budget, there are proven technologies – from 0.5 to 5,000 m³ storage volume, from individual families to village supply for 500+ residents. 

• PE Rainwater Tank (0.5–10 m³) : Best entry-level solution. UV-stabilised, ready to use immediately, no specialist skills required. Lifespan 15–25 years. 

• IBC Container (1 m³) : Cheapest immediate solution. Limited lifespan (3–5 years), UV protection recommended. Ideal as a transitional solution. 

• Collapsible / Bladder Tank (1–500 m³) : First choice for emergency relief. Rapid deployment, easily transportable. Standard for UNHCR and Red Cross. 

• Roof Rainwater Harvesting (0.5–50 m³) : A 100 m² roof yields up to 80,000–150,000 L/year in the tropics. Ideal for schools and community centres. 

• First-Flush System (supplement) : Automatically diverts contaminated initial runoff. Essential addition to rainwater harvesting. DIY construction possible. 

• Sand Dam (500–5,000 m³) : Stores millions of litres in riverbed sand, protected from evaporation. Built with local materials and community labour. Lifespan 50+ years. Proven in Kenya, Tanzania, Ethiopia. 

• Earth Tank / Berkad (5–500 m³) : Simple excavation with HDPE liner.

• Underground Cistern (5–100 m³) : Ferrocement/reinforced concrete, cool underground storage reduces microbial growth. Ideal for institutions.

  Lifespan 30+ years. 

• Johad / Earth Bund Pond (50–5,000 m³) : Captures surface runoff and recharges groundwater.

THE KEY ADVANTAGES OF THESE SOLUTIONS 

• Low maintenance requirements : Passive systems with no moving parts. Lifespan 20–50+ years with minimal annual inspection. 

• Use of local materials : Sand dams, berkads and johads built from earth, sand, stones and concrete. Ceramic filters and biosand filters can be manufactured locally. 

• Power supply only when needed : The majority operate without electricity. Where required, a small solar panel (50–100 W) is sufficient for a 12V pump. No diesel, no grid connection. 

• Scalable from 0.5 to 5,000 m³ : From a single IBC container to a sand dam. Step-by-step expansion possible. 

• Community-suitable and climate-resilient : Community construction and operation. Bridges dry periods and strengthens resilience. 

POWER SUPPLY – ONLY WHEN NEEDED 

• No electricity : Gravity, hand pump or rope pump. The Afridev hand pump is the standard in East Africa. 

• Small solar : 12V DC pump + 50–100 Wp panel. Up to 4,000 L/h. 

• Medium solar : Grundfos SQFlex + 300–600 Wp. Up to 5,000 L/h, up to 70 m head. AC/DC without inverter. Proven across Africa. 

• Generator backup : Petrol motor pump 2". Up to 40,000 L/h. Emergency reserve only. 

WHAT ACCESSORIES ARE NEEDED FOR OPERATION ? 

All components are designed for regional requirements: high UV exposure, limited skilled labour, long supply routes. 

• Pumps and conveyance : Hand pump, rope pump, Afridev, solar submersible pump 12V, Grundfos SQFlex, motor pump 2" 

• Solar technology and energy : Solar panels 50–600 Wp, charge controller/MPPT, battery AGM/LiFePO4, generator 2–3 kW 

• Pipes and fittings : HDPE pipe 25–32 mm, flexible hose, suction hose 2", lay-flat hose 2", gutters, PE fittings 

• Water treatment : Chlorine tablets, ceramic filter, biosand filter, SODIS, first-flush diverter, water test kit 

• Construction materials (mostly locally available): Cement, reinforcement steel, HDPE geomembrane, geotextile protective fleece, evaporation protection sheeting  

• Installation and tools : Plumber's tool set, earthwork tools, tank stand, repair kit, universal toolbox 

• Protection, hygiene and training : Water canisters 20 L, Hippo Water Roller, Tippy Tap, soap, WASH training materials, spare parts stock 

WATER TREATMENT – FROM STORAGE TO DRINKING WATER 

Stored water is not automatically drinking water. The WHO recommends a double barrier: disinfection combined with filtration. 

• Chlorine tablets (NaDCC/Aquatabs) : 99.9 % bacteria/viruses. 1 tablet = 20 L, 30 minutes. 

• Ceramic filter (Potters for Peace) : 99.9 % bacteria + turbidity. 2–3 L/h. Can be manufactured locally (KE, GH, TZ, NG). 

• Biosand filter (CAWST) : 90–99 % bacteria. Made from local materials. 40–60 L/h. Free construction plans available. 

• SODIS / Solar disinfection : 2L PET bottles, 6 hours of sunlight. WHO-recommended. 

INTACT DRINKING WATER SOURCE / BOREHOLE 

Where a borehole is available or planned, it provides the most reliable source. Groundwater offers stable supply independent of seasonal fluctuations. 

Recommended combination : Solar-powered submersible pump (e.g. Grundfos SQFlex) feeds into an elevated PE tank or cistern. Gravity distribution to the community. Chlorination and filtration ensure quality. Autonomous, scalable, minimal operating costs. 

Key aspects : Regular water testing (quarterly), protection zone min. 30 m radius, proper sealing against surface water ingress, trained water committee on site, spare parts stock stored locally. 

DMH | Didaktik Manufaktur Hamburg delivers a customised, high-quality all-in-one solution that efficiently covers 80–90 % of the typical requirements – from needs assessment through supplier selection to on-site training. 

CONTACT US FOR AN INDIVDUAL QUOTATION 

Your DMH Team !