1. WASH Cluster – Emergency Training DR DR1 1 DRAINAGE Session 1 Introduction

2. WASH Cluster – Emergency Training DR Aims To be able to plan an appropriate drainage intervention to effectively and safely remove water from sites occupied by disaster affected people, thus improving their environmental health and living conditions. DR1 2

3. WASH Cluster – Emergency Training DR Objectives (1) Participants will be able to: Describe the main reasons why standing water, flooding and excessive erosion occurs. List the main risks due to inadequate drainage Make a preliminary plan for an appropriate drainage intervention, considering topography, soil conditions, and site layout. Apply the basic principles of good drainage design and how to choose the most appropriate method according to the local conditions. DR1 3

4. WASH Cluster – Emergency Training DR Objectives (2)Participants will be able to: Recognise the different drainage components, materials, tools, equipment and staffing required to implement a drainage intervention. Apply the sphere guidelines for drainage. DR1 4

5. WASH Cluster – Emergency Training DR Where does excessive water come from and why does it cause a problem in emergencies? DR1 5

6. WASH Cluster – Emergency Training DR Why is this a problem in Emergencies? People stay in unsuitable areas due to security and land availability Standing water provides breeding sites for disease carrying vectors (mosquitoes), hosts water bourne diseases Flooding of latrines, shelters creates an unhealthy and unpleasant (muddy) environment People may have a lower resistance to disease as a result of the emergency. DR1 6

7. WASH Cluster – Emergency Training DR Excessive surface water due to: Direct Precipitation on site (rain, snow ) Impact varies with the Intensity (mm/hr) and Duration (hr) of the rainfall, topography (low points), soil conditions An already soaked soil will have little absorption for new rains Drainage is needed to remove the excess water or ponding will occur DR1 7

8. WASH Cluster – Emergency Training DR FLOODING (off site source) Rivers and streams, can overflow their banks in rainy seasons Spring Tides and Surges can cause inundation from the sea. Lakes can rise from extra inflow. Flooding can be incremental or sudden (flash floods in hilly catchments) site selection is important DR1 8

9. WASH Cluster – Emergency Training DR WASTE WATER Grey Water/ Sullage Water spillage, kitchens, clothes and body washing areas not rain water Water spilled at taps and pumps Black/ Sewage (sanitation) Water from flushing toilets and septic tanks, overflowing latrines DR1 9

10. WASH Cluster – Emergency Training DR DR1 10 Faecal contamination Mosquitoes Flies, cockroaches, rats Drowning Psychological impact Risk of damage to buildings and roads What are the problems?