CAUTION

Articles which are only delivered as part of a kit (motor pumps, water tanks, pipework, tools and sprayers) are not described in the Logistic Catalogue, but can be found in the Kit Catalogue (KWAT).

MSF REFERENCE DOCUMENT

"Public Health Engineering In Precarious Situations"

This guide is a reference manual for engineers, logisticians, and all those concerned with environmental health in humanitarian relief operations associated with natural disasters or conflicts.

You will find in it information on water supply, sanitation, wastewater and sewage disposal, waste management, dead body management and vector control.

The book's main focus is on technical aspects and equipment; it does not cover hygiene promotion, but gives references to other books that do.

NEEDS ASSESSMENT FOR EQUIPMENT

1. Water needed

• What is the target population? (Take account of possible fluctuations in the future.)
• Is MSF in charge of water supply for the whole population?
• What quantity of water do you plan to supply per person per day?
• 5 l is a strict minimum during the emergency phase.
• 10 l is acceptable for a transitional period.
• 20 l should be the standard for the medium and long term.
• What quantity of water do you need for medical facilities?
• Feeding centre: 30 l/person/day
• Dispensary: 5 l/consultation
• Hospital: 50 l/bed/day (40 - 60 l)

NB: You should add 15% to account for losses during distribution and transportation.

• How many distribution points are necessary?
• How many times a day can you fill the tanks?

2. Water available

• What types of water source are available? Rain, lake, river, spring, well, borehole, etc.
• How far away are these sources?
• Should transportation be by pipe or by truck?
• What is the water quality?
• Do you suspect faecal contamination?
• Do you need a water testing kit?
• In all situations, chlorination should be organised. In some cases, it should be combined with sedimentation (in 30 m³ tanks), or filtration (water treatment plant).
• Draw a plan of your camp to review your projected water supply network: how many sites, pipes, roads, access points etc.

3. Equipment needed

Taking account of the answers to the questions above and of your map, you should define your needs in terms of MSF standard kits and modules, which are presented in this catalogue.

EXAMPLE

A population of 30000 people is placed in a camp with water available 200 m away. MSF is responsible for providing water to the whole camp for 2 months.

Water needed

• For the population: 30000 people x 10 litre/person (transitional period) = 300 m³/day
• For the medical facilities:
• feeding centre: 80 patients x 30 litre/patient/day = 2400 litre/day
• hospital: 20 beds x 50 litre/bed/day = 1000 litre/day
• total: 3400 litre/day
• Total water required: 300 + 3.4 + 15% = 350 m³/day

Distribution

• For the population:
• 1 distribution ramp = 6 taps = 6 x 250 people = 1500 people
• 30000/1500 = 20 ramps = 10 water distribution modules
• rule of thumb:
• minimum storage = 5 l / person
• => 30000 x 5 l = 150 m³ total storage capacity required
• => 150 m³ / 15 m³ tank = 10 tanks to be ordered
• For the medical facilities:
• 2 days' storage capacity is mandatory
• feeding centre: 2.4 m³ x 2 days = 4.8 m³ => order tank of 5 m³
• hospital: 1 m³ x 2 days = 2 m³ => order tank of 2 m³
• The facilities, being a long way from the river, will be supplied by a 5 m³ tanker truck.

Sedimentation

• A tank of 30 m³ has a height of 1.5 m. Sedimentation takes place at 100 cm/hr.
• 150/100 = 1.5 hrs to 2 hrs is needed for the sedimentation of a full tank + count 1 hr for filling the tank and 1 hr for emptying it => total time required = 3.5 to 4 hrs
• 5 batches of 25 m³ can be made in one day (no night work) => one tank can produce 125 m³ per day
• Tanks required: 350 m³/ 125 m³ = 3 tanks of 30 m³ are needed

Water chlorination

• 1 kit contains 15 kg of chlorine, enough for 10,000 people for one week => for 30,000 people 3 kits are necessary
• Additional chlorine calculations: for 30,000 people over two months, 405 kg of chlorine are necessary. Minus the first 45 kg in the kits => order 360 kg of chlorine

Water pumps

• 1 pump for sedimentation
• 1 pump for tanker truck
• 2 pumps for the rest of the distribution
• (diesel or petrol, depending on the fuel available)

Piping

• The map of the network shows a total requirement of 480 m of piping.
• The kits (pumps and tanks) already provide a significant quantity of piping, so order 2 modules of additional piping to complete.

Others

• 2 water supply toolkits
• 2 2"/3" adaptation kits

Hand pumps

Hand pumps are manually operated pumps, using human power to lift water from boreholes or wells.

Different hand pump types are used, depending on the depth of the water level, the required yield and the pumps available.

When choosing a hand pump, always keep in mind that the column of water is getting very heavy at greater depth and can be very difficult to lift, especially for women and children who are mainly responsible for collecting water.