New drinking water and toilet projects
Water supply for the two villages Ambohitrandriana and Mahavanona in North Madagascar
Life in the two villages
The two villages with about 6500 inhabitants are located in northern Madagascar on the Sambirano river. Outside the rainy season, access is possible with off-road vehicles, during the rainy season only with a motocross motorcycle or a motor canoe on the Sambirano River.
The residents live in the simplest of conditions from the cultivation of cocoa, vanilla and rice.
Although the Sambirano River carries a lot of water, many people in the villages on the banks of the river do not have clean drinking water.
Most families have 4-6 children, but no clean drinking water and no toilets.
The whole family lives and sleeps in a simple hut with a single room.
The water from this well is not clean!
The dishes are washed at the river.
The secondary school without toilets.
An open-air ladies hairdressing salon (without tap).
A "down-to-earth" tailor's studio.
A launderette without running water.
Goals and scope of our project
With the support of Preisig AG, WatSanAid has taken on the task of planning and constructing a water supply system for the two settlements. The water supply consists of a stream reservoir, drinking water treatment with pre-filter, slow sand filter, reservoir 100 m3, water pipe network and various public water distribution points.
The construction work
Procurement and transport of the required material
Most of the required material could be procured in Madagascar. Material, equipment and tools that are not available in Madagascar had to be provided in Switzerland. Various suppliers of Preisig AG supported us and provided material free of charge. The MadagasCare Foundation in Basel has helped us in an exemplary manner with the forwarding and customs clearance of the material in Madagascar.
The preparatory works
The whole family helps with laborious manual work when breaking gravel.
Gravel sorted by grain size for drinking water filters
Part of the team of the entrepreneur EC Abraham.
Approximately 5 km of pipeline trenches have been dug by hand and covered again.
Urs Kurz from +GF+ put together all the products and equipment supplied to us by Georg Fischer.
Eight pallets with material that is not available in Madagascar are ready for transport to Madagascar.
The road conditions are bad. Transporting material with ox carts is often the only solution.
In the rainy season the road is often flooded. Access to the two villages by vehicle is then almost impossible.
The construction work for the damming of the Tsimananbignany is completed
The Tsimanambignany creek
The side wall for the damming of the Tsimanambignany creek.
The water outlet shaft for conveying the water to the filtration system.
Village chief and construction supervisor visiting the dam.
The dam wall is completed.
The construction work for the reservoir and the water filtration system
The construction pit for the water reservoir.
Cement, gravel and sand are mixed into concrete by hand.
The water reservoir is ready for concreting.
Formwork and reinforcement work for the drinking water filter system.
Drinking water filter system and water reservoir, prepared for concreting.
The concreting work for the Slow Sand Filter is completed.
On the right of the picture are the two pre-filters. The raw water from the damming of the stream flows in these pre-filters from bottom to top.
The gravel layers in the pre-filters have a finer grain size from bottom to top. Impurities in the water remain in the gravel layers.
The pre-cleaned water flows through this pipe system from the pre-filter to the slow sand filter. The pre-filters must be regularly backwashed with the large backwash flaps on the right of the picture.
Cement boards are the supporting structure for the lowest layer of gravel in the Slow Sandfiter. Through the gaps in this structure, the cleaned water in the cavity below flows to the outlet and on to the water reservoir.
A layer of gravel lies over the supporting structure as a base for the filter layer of sand.
Above the gravel layer is the filter layer of fine-grained clean sand. On the surface of this layer the so-called "Schmutzdecke" is formed, which eliminates all pathogenic germs in the water.
Prefilter and Slow Sand Filter are double-guided so that one line can always remain in operation during maintenance work.
The raw water from the stream impoundment is coarsely cleaned in the backwashable pre-filter and biologically purified in the slow sand filter.
Construction of the water pipelines in connection with vocational training by Mario Castelli.
The expert Mario Castelli has arrived after an arduous journey.
The pipe material in polyethylene is already in place.
The first technical lesson lesson for the welding of polyethylene pipes.
TRAINING OJECTIVE 1: Connecting the PE drinking water pipes with mirror welding
Mario Castelli explains the mirror welding process to the local fitters of entrepreneur E.C. Abraham.
This older mirror welding machine was made available to us by the Zurich water supply company.
The employees of E.C. Abraham are very interested in getting to know this unknown procedure.
TRAINING OBJECTIVE 2: connecting PE drinking water pipes, branches, bends and gate valves with Elektro welding sockets
The fitters from Mario Castelli, how to prepare the pipe ends for a +GF+ electrofusion sockets. The fitters work very reliably.
Welding PE pipes with +GF+ welding sockets is already a well-established routine
The school children are also interested in the construction of the new water pipes and the working methods of the local skilled workers.
+GF+ pipe branches are professionally installed in the drinking water pipeline by local technicians.
Preparation of a Hawle stop valve for installation in the drinking water pipeline network.
A Hawle stop gate valve is welded into the drinking water network using +GF+ electrofusion sockets.
Tapping clamp +GF+, suitable for the connection of branch pipes to the main pipe
Tapping clamps +GF+ can also be installed on pressurised main lines.
Connection pipes with Hawle shut-off valves between the two Slow Sand Filters and the reservoir.
The PEHD pipes also supply the village part of Mahavanona with drinking water.
Strong young men pull the pipes to the desired location
The public water points
Six of the total of nine water points are designed as communal washhouses. Under the extension of the roof there is a laundry hang to dry the laundry.
A washhouse with a roof as protection against strong sunlight and wetness when it rains is a previously unknown comfort in this area.
A basin for washing dishes and clothes is a welcome novelty. The storage table next to the basin and the roof covering still have to be built.
With the tap at the back of the watering place, the jerry cans are filled and carried home. On the lower left is the water meter for invoicing the consumption.
Our building contractor in Madagascar
The company Engineering Consulting Abraham, Lot B 363, Anatihazo, Isotry, Antananarivo, carried out the entire work on our behalf.
E.C.Abraham will also take over the responsibility for operation and maintenance of this water supply after completion of the water plant.
Contact : Hery Abraham RAKOTOMANANTSOA <[email protected]>
Persons, companies and organisations who have supported us in this project:
- Department of Finance of the City of Zurich, CH 8036 Zurich, start-up financing.
- Martin Wegelin, dipl. Bauing. ETH, CH 7208 Malans, consulting on the design of water filtration.
- Regula Ochsner, President ADES Madagascar, CH 8913 Ottenbach, advice and information on customs and traditions in Madagascar.
- Urs Kurz, Technical Advisor Georg Fischer AG, CH 8240 Thayngen, Technical advice on pipeline construction, material, equipment and tool procurement.
- Mario Castelli, CH 5210 Windisch, instruction of the skilled workers and supervision of pipeline construction on the construction site in Madagascar.
- Eric Voyame, CH 4106 Therwil, Foundation MadagasCare, material.
PE - Piping material, equipment and tools
Water meter
Outlet taps
Water stop valves
Project management and financing
Wash troughs
Co-financing
PE welding machine