WASH Cluster – Drainage
DR2
Session Plan
DR2 - Strategy
Example Timetable
½ day 3.5 hours total
DR1Introduction
Reasons for
Drainage
DR2Strategy
10 mins
DR3- Site
Conditions
30 mins
DR4- Drainage
Solutions
Exercise and
summary
30 mins
DR5Drainage
design
50 mins
50 mins
DR6- Key
points
Summary
10 mins
Session-at-a-Glance
Session Activities
Approx.
Time
Instructional Activity
10
Group discussion around effects of
topography
Site investigation
Discussion about waste water
5
Drainage in SPHERE
5
What to consider when designing
drainage schemes
Total time
10
Group discussion using flow
diagram
Work in pairs to define design
criteria
30 minutes
Session Aims
 Outline how the natural drainage catchment causes drainage on a site, how to identify problems
and make the strategic choice for a drainage intervention.
Session Objectives
At the end of the session participants should be able:
 Describe how to make a preliminary assessment of the drainage problems in a catchment
 Choose an appropriate drainage intervention strategy
 Summarise the sphere drainage standard
Session Materials

Computer and projector

Flip chart paper and pens

Access to Sphere

This Session Plan, Trainer’s Notes

WASH DR Powerpoint

Printout of Powerpoint (include slide notes for Trainer)

Handouts for participants
-
OXFAM ‘Low cost drainage for emergencies’, Technical Brief 4’:
-
Trainers Notes Handout
-
Participants Notes Handout (reduced version of trainers handout, includes case
studies)
-
PowerPoint (no notes included)
1
WASH Cluster – Drainage
DR2
Key Messages

The drainage problems on a site are influenced by the pre-existing position of the site within
the natural drainage catchment

Assess the drainage risks due to the topography of the surrounding land

Estimate the likely drainage risks due to site slope, upstream conditions, groundwater

Make a drainage strategy based on the likely risks and outline your waste water
management process

Describe Sphere guidance on drainage

Key design information needed is quantity of water expected, type of water, soil type and
ground conditions, slope, expected rainfall and evaporation, availability and type of local
materials
Facilitator Guidance
This session outlines the influence of the site location within the natural drainage catchment and
how this effects the type of likely drainage problem that will be encountered on the site.
Outline how the natural drainage catchment causes drainage problems on a site, how to identify
problems and make the strategic choice for a drainage intervention.
This session is run as a group discussion, using the powerpoints to summarise and introduce the
key messages. The slides run from assessing the likely drainage risks due to where the site lies in
the catchment, then making a waste water management plan, i.e. a process plan to deal with the
problem and to introduce the sphere standards on drainage.
Session Plan
Important to consider where the site is within the natural drainage
catchment
In an urban area contact with the relevant municipal organisation for
information on the drainage infrastructure.
Topographic survey- use contoured maps or level equipment/ GPS
Are there existing drainage channels either natural or man-made? If the
site is within a river catchment a proportion of this catchment (above the
site) will contribute water flows towards the site.
Large infrastructure works need to be agreed with camp planners/
managers.
Within the site, a level survey will determine the slopes in the site, thus
showing where the water will drain and collect, this will identify where
potential drainage will be required.
The larger the upstream catchment feeding the site, the greater the
potential inflow of surface water.
Site location is chosen at camp planning/ settlement planning stage,
drainage is one of the factors to be considered, an unsuitable site (such a
low lying marshland, flat or steep (>5%) may be difficult to protect
adequately from flooding or to provide drainage and may require major
drainage infrastructure
A guide to consider the source, hazard, volume of waste water to be
dealt with
Session Plan – DR2
2
WASH Cluster – Drainage
DR2
The purpose of Drainage in Emergencies
Reference sphere: 2004 edition (under review 2010) Humanitarian
Charter and minimum standards in disaster response,
Chapter 2 Minimum standards in water supply, sanitation and Hygiene
Promotion, section 6 drainage p 86-88.
Appendix 1 Water supply and sanitation initial needs assessment
checklist, part 6 drainage p92
This is a direct quote from sphere on drainage, which shows how simple
and key the drainage assessment is, Participants need access to sphere
and the above references available as a handout.
Based on previous slides, the criteria for design becomes clear
Trainer could ask participants to come up with design criteria in pairs
Discuss in pairs for 5 minutes and then come back in plenary for 5 mins
Session Plan – DR2
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