1. WASH Cluster – Water in Emergencies W W4 1 Water in Emergencies Session 4 Water Sources, Treatment & Implications

2. WASH Cluster – Water in Emergencies W W4 2 Water Supply StagesWater abstraction Raw water storage Pre- treatment (such as roughing filtration) Coagulation / Flocculation / Sedimentation or Slow sand filtration ChlorinationStorageDistribution Water supply in emergency contexts may involve some or all of the above stages Adapted form: Davies & Lambert (2002) Engineering in Emergencies, REDR / ITDG

3. WASH Cluster – Water in Emergencies W W4 3 Criteria for selection Water source, treatment & supply Ease / ability to obtain an acceptable quality? Impacts of development? Existing users Aquifers Environment Time of set up vs urgency? Technical Resource / logistical Costs? Capital O&M Ease of O&M? Requirements Resource / logistical Availability of trained staff Management, legal, security, socio- political & cultural constraints? Management Land ownership Security Cultural & socio-political issues Acceptable yield? Demand vs yield Seasonal yield Future yield Adapted form: House & Reed (1997) Emergency Water Sources, WEDC

4. WASH Cluster – Water in Emergencies W W4 4 Shallow & Medium Depth Groundwater Shallow well, Lao PDR S House / ACF Handpump on shallow borehole, Liberia S House / ACF

5. WASH Cluster – Water in Emergencies W W4 5 Springs Piped Supplies Piped supply from motorised borehole, IDP camp, northern Uganda S House / MSF-OCBA Spring being protected, Zaire S House / WEDC

6. WASH Cluster – Water in Emergencies W W4 6 Deep Groundwater Surface Water Submersible pump S House / WaterAid Surface water sources supplying refugee camps, Zaire S House / MSF-OCBA

7. WASH Cluster – Water in Emergencies W W4 7 Rainwater Roof collected Ground collected Health facility in an IDP camp, northern Uganda S House / MSF-OCBA Birkad underground rainwater collection tank, northern Kenya S House / AAH-US

8. WASH Cluster – Water in Emergencies W W4 8 Implications of selection of Water Source and Supply

9. WASH Cluster – Water in Emergencies W W4 9 Scenarios 1.Spring located above an IDP camp, used by the local community, sited on a private landowners land 2.Shallow wells developed in a wooded area outside an IDP camp for people displaced by a conflict 3.Water is being tankered from one part of a city which is under control of one armed group and has to pass through the area of another armed group before reaching its point of supply to a group of displaced people 4.Water is being piped from a seasonal stream being fed from a spring in a mountainous area following a major earthquake, aftershocks are still being felt 5.100,000 displaced persons due to conflict arrive in a semi-arid area and new boreholes are drilled to supply the camps

10. WASH Cluster – Water in Emergencies W W4 10 Implications of Selection of Source & Supply Exercise - Consider the particular scenario provided to you and consider the following: 1.What are the risks / potential negative implications apparent in the scenario and to what or whom? 2.How could you reduce the risk?

11. WASH Cluster – Water in Emergencies W W4 11 Water Treatment Most common water treatment = chlorination Chlorination works most effectively with low turbidity of 1 NTU (or max 20 NTU) Guidelines for chlorination given for pH<8, turbidity <5 NTU, temperature approx 20 o C, 30 min retention time If pH higher, temp lower or turbidity higher then adjust processes

12. WASH Cluster – Water in Emergencies W W4 12 Pre-Treatment Pre-treatment: –Roughing filtration –Coagulation, flocculation & sedimentation –Rapid sand filtration Other treatment: –Slow sand filters - but also need pre-treatment to reduce turbidity –Water treatment kits - various methods

13. WASH Cluster – Water in Emergencies W W4 13 Bulk Water Treatment Coagulation & flocculation Safety needed with chemicals… Zaire (DRC) S House / WEDC Ethiopia S House / WEDC Pakistan S House / OXFAM-GB Field ‘Jar test’

14. WASH Cluster – Water in Emergencies W W4 14 Chlorination Practical handout on chlorination provided

15. WASH Cluster – Water in Emergencies W W4 15 Household water treatment Candle filters Ceramic pot filters Biosand household filters Chlorination Boiling Sodis – using UV light & plastic bottles Local natural coagulants Cambodia H Jones / WEDC Moringa Oliefera Waterlines

16. WASH Cluster – Water in Emergencies W W4 16 Candle filter units OXFAM-GB

17. WASH Cluster – Water in Emergencies W W4 17 Bulk vs Household Treatment +- Bulk water treatment Can supply to large numbers of people Can supply quickly Can control water quality Can monitor changing water needs Not useful for dispersed populations High O&M inputs Water can be contaminated post-supply Household water treatment More control for householders More sustainable (if appropriate to situation) Less risk of contamination post treatment Good for disperse populations Training needed for effective use More difficult to supply large numbers of people Limited control on effective use