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Monitoring
of water supply coverage
Author:
Kristof Bostoen, February 2005
Quality assurance: Sandy Cairncross
Monitoring
of water supply coverage will help to ensure water
supply for the millions of people who still lack
convenient access to a safe, reliable and
affordable water source.
According to the WHO/UNICEF Joint Monitoring
Programme, more than one in four people in the
developing world lack access to water (WHO/UNICEF
2004). Targets have been set in the Millennium
Development Goals (MDG) to accelerate the
improvement of this situation. Quantifying access
through monitoring will be essential to attain such
goals, although the process to achieve these
goals will be as important in order to
achieve sustainable coverage.
This
fact sheet aims to clarify different steps involved
in measuring access to water by water coverage
surveys and highlight some of the problems that may
affect current monitoring.
There
is a common misconception that monitoring should
only be done by specialised professionals. However,
everybody uses similar techniques in their daily
lives. When we buy fruit or vegetables we look at
them, feel them or even smell them to assess the
quality of the product. When all of them cannot be
checked individually, we examine a small sample and
consider it representative enough to give the buyer
confidence in what is being purchased. Monitoring
uses a similar process of sampling when a number of
households is asked in a survey about their access
to water. While, monitoring statistics may often
appear daunting, they are in reality only a small
part of the monitoring process, as shown below.
Despite their small role, the statistics are often
given a central place.
Different steps in the
monitoring process cycle
Monitoring
is not a stand-alone activity but a
tool used to feed information into other
activities. It can be divided into different steps
as shown in Figure 1
. The first four steps (
Why,
What,
How and
Validate) relate to the definition and indicators to
be measured, while the three following steps (
Sample,
Analyse and
Infer) are about the representative data collection
and analysis. Often statistics is seen as the
central part of monitoring, but in fact only one
step in the whole process, step
(analyse), uses statistical formulae. Steps , ,, and
follow
the data analysis and feed back to the need (
Why Measure?) for a future round of data collection.
The
rest of this document will cover the various steps
of Figure 1
in more detail.
Figure 1:
Steps in monitoring of coverage
1. Why measure
water supply coverage
Monitoring
can help to do any of the following:
-
Set goals, targets, policies
and tariffs;
-
Quantify
how many people or households have access to
water;
-
Make
regional, national or international comparisons.
-
Appraise
water supply targets set by public and private
authorities;
-
Understand why
people do not have access to water;
-
Target
those people lacking access by identifying
and locating them;
-
Measure sustainability
of access for people who do have a water supply;
-
Plan more
effective targeting of resources (equity
and scaling up);
-
Identify
coverage deficiencies;
-
Make better
management decisions;
-
Target pro-poor
and gender-sensitive policies and actions;
-
Engage in
sector advocacy at regional, national and
international level;
-
Control
costs;
-
Plan
operation and maintenance
Collecting
water coverage information without any clear
purpose or failing to use collected data is a
waste of resources, money and staff time as well
as the other peoples time, including the target
population.
Despite
the importance of collecting information it is
surprising how little measuring actually happens and
how often monitoring is used only for reporting.
2. What do we
want to measure?
First
of all we need to define
clearly what to measure. In terms of water coverage,
possible definitions could be:
Water in adequate quantity for hygiene purposes
and of adequate quality for human
consumption.
or
Access
to a reliable
source of water which supplies adequate
quantity and
adequate quality of water in a convenient
way.
Although
these definitions seem clear, they still cannot be
measured as they lack clear measurable outcomes.
Terms like convenient, reliable, a source,
adequate quantity and adequate quality
need to be defined so they become objectively
measurable.
One
of the factors of a reliable
source might be that it is not intermittent. A measurable
definition of reliable could be a source
that is available without
a day of interrupted supply in the past 7 days.
This might not be a complete description of a reliable
source, but it is a clear and satisfactory
measurable definition for monitoring.
It
is often impossible to measure a variable of
interest in large household surveys. For instance,
to assess water quality might require expensive
laboratory tests. The type
of water source such as piped
water (often good quality) or river
water (often bad quality) could then be used
as an indicator being close to the information
required. The type
of water source is referred to as a
measurable proxy
indicator for water
quality. Although this is not always a perfect
proxy it helps to get a better idea of water quality
through a measurable
indicator.
Households
do not always use a single source of water. In rural
areas in particular, seasonal changes often occur.
Where seasonality and multiple sources are relevant
to coverage, definitions and measurable indicators
might have to take this into account. An indicator
can be built up from multiple answers, as often a
single question cannot elicit all the critical
aspects of access.
Definitions
are context-specific. The poor would have a
different definition for access from the more
affluent, a government or a funding agency. Women,
involved in the day-to-day water collection, will
define access to water differently from men.
Involving the target population in defining
access (and how to collect the necessary
information) will promote a consensus among the
target population and give a better understanding
into the local water access problems.
Benefits
from water supply can only be achieved if water
sources are used. In measuring coverage there is
often discussion about whether use (which is
practice) should be measured, or access
(Which is more theoretical, but for which providers
can more easily be accountable)
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Type
of information collected in a survey

Qualitative
Quantitative
Method
of collecting
data in a survey

Participatory
Non-Participatory
(Target
population is involved in data
collection)
(External people do data collection)
Time
span of data collection

Continuous
Point in time observation
(Routine
data
collection)
(Over brief period to take a snapshot of a
situation) |
Figure
2: Aspects of data collection for water coverage
monitoring in a survey
3.
How
to measure water coverage
There
are different ways of collecting water-related data
and the methodology will depend largely on the
purpose of the monitoring work and the resources
available for it. No single data collection method
will be able to provide all the information needed
for projects as different types of information will
be collected in different ways.
There are
two main and complementary methodologies in data
collection; qualitative and quantitative methods. Quantitative
methods aim to measure a small number of
quantitative indicators and characterise these in
figures. Quantitative data such as water coverage
are often expressed in percentages of people or
households having or not having access.
Qualitative methods are more exploratory and analytic, seeking a
diagnosis or description of a problem.
They are also better able to discover
information that was unexpected and therefore not
explicitly asked for in the survey.
-
Typical
Quantitative information could be: 35% of
people have access to 'improved' water sources.
In Urban areas this becomes 52% (+/-10%) while
in rural areas the coverage is 27% (+/-15%)
-
Qualitative
information could be: 'households struggle with
daily water payments at the beginning of each
month after paying the rent, which makes them
use river water for drinking at that time'.
Some
qualitative approaches have been proposed lately,
which aim to quantify qualitative data to facilitate
interpretation and comparison
(van Wijk 2001)
. This blurs the line between the two approaches.
Other
aspects of data collection are:
Participatory
methods aim for a high involvement of the target
population in the process of data collection, while
non-participatory methods use mainly professional
external people for data collection.
Continuous
or
routine data collection is a continuous process
of collecting and updating information, which is in
contrast with point
in time activities such as surveys
which aim to collect information over a short
period.
Survey
methodologies often use a mix of approaches to
collect data and the way each factor will be used
can vary on a scale between the extremes shown in
Figure 2. Often coverage data will be collected over
a short period to obtain a point estimate. They
generally are quantitative, non-participatory
cross-sectional survey (as illustrated in the right
column of the scale in Figure 2.). This is also the
focus of this fact sheet, but it is not the only or
preferred way of obtaining accurate data.
Usually
water coverage surveys are done in a
non-participatory way by an interviewer asking
questions. However people can or do not always
answer the questions
accurately, so other methods of data collection like
spot
observations and demonstrations,
should be considered. Information collected through
different methods can be compared to check its
validity. This is called triangulation.
Validation
is the part where what
is measured and how
it is measured is scrutinised to make sure that it
can give the information for which the data were
collected. Validation is often not a part of a
survey as it needs far more information and rigour
in data collection than the basic data collection.
However the collected data and the method of
collection have to be based on some type of past
validation before being included in a survey.
Typically validation would compare the collected
data with information which is judged to be as
reliable as possible. This can be done during
pre-testing, which is essential before any survey
and consists of doing a small survey in a similar
population under similar conditions. For example, if
the type of water source is used as a proxy for
water quality, a sub-sample during the survey can be
submitted to more rigorous tests such as water
quality tests to determine if water quality is
related to the type of water source as has been
assumed.
Validation
should not be limited to what
is being measured, but how
it is collected. When data are collected by asking a
question, validation involves checking whether the
people are able or inclined to give accurate
information.
Water
collection time is often used as a proxy for water
quantity according to the relationship shown in.
However, it might be useful to measure both, in
order to confirm this relationship for a local
context. It is also essential to verify if
interviewees estimate correctly the time required
for a water collection journey. The question can
compare water collection time to the duration of
certain day-to-day activities, such as the cooking
of certain foods, to obtain more reliable results.
Validation feeds back into what
and how
to measure until indicators are suitable to be used.

Figure
3: Water quantity & collection time
5.
Representative sampling
The
basic sampling unit is the unit on which the data
are collected. A practical basic
sampling unit for water coverage can be the household
because all people in the household are likely to
use the same water source at home. However for some
aspects such as sustainability of water source
or number of beneficiaries per source the water
source can be a more suitable basic sampling
unit.
Collecting
data from every household is often impossible or
impractical, so a sample of households is taken from
the target population. The conclusion based on
the sample can apply to the total population
if the sample was representative.
To
take a representative sample it will be essential
to:
-
Clearly
define the target population from which
the sample is collected;
-
Clearly
define the basic sampling unit;
-
Make
sure each basic sampling unit has an equal or
known chance of being included in the sample.
Taking
representative samples is often complex,
particularly in low income countries. It is seldom
straightforward to make a list of households which
is needed in traditional sampling methods, because
of a lack of addresses or other household locators.
Also people who have access to water are usually
clustered around a water source. This geographical
clustering of people with access to water causes
bias in the sample, and even if this bias is
controlled, it requires increased sample sizes. To
make data collection more accessible for management
and evaluation of projects, more suitable sampling
methods need to be developed.
Practical
implementation
Although
practical implementation of a survey will be crucial
to the validity of the collected data, it does not
always get the attention it deserves. Practical
implementation starts with the decision to do a
survey until the data are analysed and made
available. At each level the convenience of
implementation and the level of training received
for the task ahead will determine how valid the
outcome will be. Three particular points can be
identified:
-
If
it is difficult to identify each household
included in the sample, the interviewer might
select an alternative household which can make
the sample unrepresentative
-
Data
that are difficult for the surveyor to collect
or which are not properly and promptly noted
down can make this information unreliable
-
Coding
the work from a paper to an electronic format
for analysis can be tedious work which can
introduce errors in the data and into the
analysis
6.
Analyse
Before
any data are collected or even any pilot survey is
done, it is important to think how the collected
data will be used, what assumptions have to be made
(possibly checked) and what analysis will be done.
Necessary information is often found to be lacking
only during the analysis stage. A complete analysis
of the pilot data might help to identify such
problems in good time.
Various
agencies invest in water and sanitation not because
they are a basic right, but to improve public
health. Often there is a temptation to measure the
health impacts of water and sanitation in such
programmes as the outcome. However this has many
pitfalls, and often results in meaningless results.
(For
more info see
http://www.lboro.ac.uk/well/resources/fact-sheets-htm/mthiws.htm
)
Once
the sample is analysed, it becomes possible to apply
the results to the whole of the target population.
This is possible only if the sample was representative.
Questions
worth asking include: Do all groups of people, even
marginal groups, have an equal chance of being
included in the sample? How could excluded groups
affect the result? Also those values missing due to
non-response are worth analysing when possible. It
enables us to document limitations of the methods
used and problems encountered, which will add
credibility to the analysis.
In
statistical jargon, the process of assuming that
results from the sample are also true for the
population is called inferring
or inference.
Correct
analysis of a non-representative sample will give
a result that is not representative for the
population as a whole. Therefore, no inference or conclusions
can be made from it that will be valid for the
whole population.
8.
Conclude
9. Action
There
is a difference between analysing sample data
(statistical work) and the analysing of results (a
managerial responsibility). The conclusions drawn
from the statistical results will feed into step
action. One action will be to define the
information for the next round of data collection
which will feed back into step
why?. An additional need in a consequent round
of data collection could be to make the collected
data comparable with data previously collected, in
order to measure the extent of progress.
10.
Storage, documenting and dissemination of data
Surveys
are often done by people external to the surveyed
population. The collected data are often not used
outside the organisation for which they have been
collected which makes them de
facto the sole owner of the data, despite
the rights of the target population.
Information
is crucial to any decision and advocacy process.
Collected information should be documented for
possible further use and where possible made
accessible to a wider public. Water coverage data
should be disseminated vertically, i.e. aggregated
(upwards) or disaggregated (downwards) as well as
disseminated horizontally among different sectors.
Documenting
data and data analysis is essential but requires
additional resources such as time and funding which
have to be allocated. This is particularly true for
data sets and data analysis that are made freely
available to the public.
Cost-benefit
of monitoring activities
With
resources in short supply, authorities are often
reluctant to get involved in data collection, as
these activities appear to have no direct impact on
beneficiaries. This is particularly true if the
authorities are uncomfortable (or unfamiliar) with
collecting such data. However, accurate data can
allow better targeting of resources and can help to
justify further investment. Monitoring can often
help to make substantial savings and to avoid
redundant activities. It can help to justify actions
that are counter-intuitive.
Useful
tools for surveys
Various
simple tools are an invaluable help during surveys.
For instance, an automatic numbering stamp ensures
unique numbering of each questionnaire form.
Free
software programs are available for entering data
into a computer and for analysis. The most popular
programs are:
EPIDATA
(recommended)
Simple
but powerful programme not requiring a powerful
computer
http://www.epidata.dk
EPI-info
http://www.cdc.gov/epiinfo/index.htm
CS-Pro
http://www.census.gov/ipc/www/cspro/index.html
Win-IDAMS
http://www.unesco.org/idams
Remarks
The
subject
Monitoring of coverage
discussed in this fact sheet is just a small
part in the monitoring efforts of the water
sector, which also includes other factors such
as user demand, and satisfaction, institutional
capacity and responsibilities, operation and
maintenance as well as environmentally sustained
services.
The
challenge is getting the best possible
information to the people who need it and then
getting those people to actually use the
information in appropriate ways for the intended
purpose.
(Patton 1990)
Further
information on assessing hygiene improvements can be
found on the Website of the former USAID
Environmental Health Project:
http://www.ehproject.org/PDF/Strategic_papers/SR-8-HISGPaperVersion.pdf
Draft
documents on the WaSH survey are available:
http://www.lshtm.ac.uk/dcvbu/hygienecentre/documentation/QForms_full.pdf
is a draft questionnaire while
http://www.lshtm.ac.uk/dcvbu/hygienecentre/documentation/KDiscussion.pdf
is a discussion document on indicator. Updated
documents in the form of a survey manual are
expected by mid 2005.
Bibliography
-
Patton,
M. Q. (1990). Qualitative evaluation and
research methods. Newbury Park, CA, Sage
Publications.
-
van
Wijk, C. (2001). The Best of Two Worlds?
Methodology for Participatory Assessment of
Community Services, IRC
-
WHO/UNICEF
(2004). Meeting the MDG drinking water and
sanitation target, a mid-term assessment of
progess www.unicef.org/publications/index_23223.html
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