APPLYING THE GUIDELINES ALONG THE SANITATION ...
12
# 1 Third edition of the WHO Guidelines for the Safe Use of Wastewater, Excreta and Greywater in Agriculture and Aquaculture Guidance note for National Programme Managers and Engineers APPLYING THE GUIDELINES ALONG THE SANITATION LADDER INTRODUCTION Writing technical guidelines which consider the economic constraints and opportunities prevalent in the diversity of countries across the globe is a challenge. The resulting text may either be an over-simplification or present a level of complexity that defeats the practical implementation of the guidelines. In both cases further explanation for implementation will be required. This Guidance Note gives examples to show how the third edition of the Guidelines for the Safe Use of Wastewater, Excreta and Greywater in Agriculture and Aquaculture (WHO, 2006) could be applied in countries at three different levels of economic development reflecting different positions on the sanitation ladder (Table 1): Low-income countries with insufficient wastewater treatment capacities and largely uncontrolled wastewater use. a) Middle-income countries trying to move from uncontrolled to controlled wastewater use. b) High income countries where wastewater is treated and wastewater irrigation is a planned process. c) Figure 1 outlines the principal application steps of the 2006 Guidelines, which form the structure for the application examples in Table 2. Tables 3 and 4 complement Table 2 with further details on options for setting health-based targets and examples of common wastewater treatment technologies by scale of irrigation and level of economic development. The Guidance Note further distinguishes between farmers’ and consumers’ safety showing, in simplified flow-charts, differences and commonalities for decision-makers in the three country groups (Figure 2ab). OMS-WSHH-Guidance-note1-20100719.indd 1 30/07/10 14:49:42
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Transcript of APPLYING THE GUIDELINES ALONG THE SANITATION ...
# 1
Third edition of the WHO Guidelines for the Safe Use of Wastewater, Excreta and Greywater in Agriculture and Aquaculture
Guidance note for National Programme Managers and Engineers
Applying the guidelines Along the sAnitAtion lAdder
INTRODUCTIONWriting technical guidelines which consider the economic constraints and opportunities prevalent in the diversity of countries
across the globe is a challenge. The resulting text may either be an over-simplification or present a level of complexity that defeats
the practical implementation of the guidelines. In both cases further explanation for implementation will be required.
This Guidance Note gives examples to show how the third edition of the Guidelines for the Safe Use of Wastewater, Excreta
and Greywater in Agriculture and Aquaculture (WHO, 2006) could be applied in countries at three different levels of economic
development reflecting different positions on the sanitation ladder (Table 1):
Low-income countries with insufficient wastewater treatment capacities and largely uncontrolled wastewater use. a)
Middle-income countries trying to move from uncontrolled to controlled wastewater use. b)
High income countries where wastewater is treated and wastewater irrigation is a planned process.c)
Figure 1 outlines the principal application steps of the 2006 Guidelines, which form the structure for the application examples in
Table 2.
Tables 3 and 4 complement Table 2 with further details on options for setting health-based targets and examples of common
wastewater treatment technologies by scale of irrigation and level of economic development.
The Guidance Note further distinguishes between farmers’ and consumers’ safety showing, in simplified flow-charts, differences
and commonalities for decision-makers in the three country groups (Figure 2ab).
OMS-WSHH-Guidance-note1-20100719.indd 1 30/07/10 14:49:42
# 2 # 3
TABLE 1. Common characteristics of wastewater use for irrigation by level of economic development
Country groupHigh-income
countriesMiddle-income countries
Low-income countries
Sanitation ladder Upper section Middle section Lower Section
Wastewater use practices
Direct use of reclaimed wastewater commonplace in agriculture and industry.
Indirect use of untreated effluents still commonplace;direct use of treated effluents on the increase.
Indirect use of untreated wastewater commonplace due to widespread pollution; direct use of untreated wastewater and fecal sludge common, especially in water and nutrient short areas.
Wastewater use policy framework
Use policies established and enforced, often within an integrated water resources management framework, especially in water-scarce areas.
Emerging policies and framework;enforcement capacity a major concern
Generally non-existent or not enforced;informal (or unplanned) use predominates
Wastewater use health issues
Pathogens under control; industrial discharges under control;primarily concerned with amenity values and exotic toxic substances.
Continued concern with helminth infections and diarrhoeal diseases;Uncontrolled industrial discharges problematic in emerging economies.
High burden of helminth infections and diarrhoeal diseases (both occupational and consumer exposure); Difficult to assess impact in households due to many confounding factors.
Drivers of wastewater use in irrigation
Water scarcity or drought; resource recovery;food security.
Water pollution and scarcity;urban food demand.
Widespread water pollution from domestic sources in and around urban areas;demand for fresh vegetables from urban centers;water scarcity;nutrient value of wastewater.
Key wastewater use countries and regions (examples)
Australia, France, Greece, Israel, Italy, Japan, Portugal, Spain, USA;Bahrain, Cyprus, Kuwait, Oman, Qatar, Saudi Arabia, UAE.
Bolivia, China, Egypt, India, Iran, Jordan, Morocco, Pakistan, Sudan, Syria, Tunisia; Argentina, Chile, Colombia, Lebanon, Libya, Mexico, Peru, South Africa.
Sub-Saharan Africa except South Africa; Yemen; some Asian countries like Viet Nam.
Source: Adapted and modified from World Bank 2010
OMS-WSHH-Guidance-note1-20100719.indd 2 30/07/10 14:49:42
# 2 # 3
FigurE 1: Key Steps of the Guideline Application Process
1. Situation analysis and health target setting
2. Identifying and validating risk reduction
measures
3. Implementation of measures
5. Verification
4. Operational monitoring
Map existing/planned wastewater use areas, practices and produce marketing •network.Assess extent of health risks (water quality, type of crop, exposure of farmer/•crop, post-harvest contamination, etc.).Prioritize health risks interventions through the • hazard analysis and critical control point (HACCP) approach and set realistic (health-based) targets which can be achieved via one or multiple risk barriers.
Identify suitable risk reduction measures together with sanitation authorities •and other concerned stakeholders (farmers, extension officers, traders etc.).Validate the efficacy, cost-effectiveness and adoptability/reliability of those •measures.
Develop an implementation plan and compare cost-effectiveness of each •planned risk reduction measure. Implement the most cost-effective measures (e.g. wastewater treatment, reuse •regulations, non-treatment options) and support their uptake/sustainability via training, incentives, etc.
Develop a monitoring plan i.e. decide on frequency, inspection points and •parameters from treatment to farm to point of consumption. Assess whether the recommended practices/standards are adopted/achieved.•If not, go back to step 2 for alternative options to reduce risks, or •step 3 for alternative options to support implementation. •
Assess to what extent the introduced measures actually achieved the set targets, •for farmers and consumers, via surveys and laboratory analysis.Compare achieved targets with available options for risk reduction and adjust •them towards impact optimization under consideration of cost-effectiveness criteria.
OMS-WSHH-Guidance-note1-20100719.indd 3 30/07/10 14:49:42
# 4 # 5
TA
BL
E 2
. P
ract
ical
exa
mpl
e of
th
e ap
plic
atio
n p
roce
ss (
see
Fig
ure
1)
in c
oun
trie
s at
dif
fere
nt
leve
ls o
n t
he
san
itat
ion
ladd
er
Ste
pA
ctiv
ity
Lev
el o
n t
he
san
itat
ion
lad
der
Hig
her
par
t
(Hig
h-i
nco
me
cou
ntr
ies)
Mid
dle
par
t
(Mid
dle
-in
com
e co
un
trie
s)
Low
er p
art
(Low
-in
com
e co
un
trie
s)
1.S
itu
atio
n
anal
ysis
Map
pin
g ar
eas
and
pra
ctic
esP
lan
ned
reu
se s
chem
es t
o be
•
map
ped
usi
ng
rem
ote
sen
sin
g.R
elat
ed f
arm
ers
and
mar
keti
ng
•en
terp
rise
s to
be
iden
tifi
ed a
nd
regi
ster
ed.
Map
pin
g of
pla
nn
ed o
r ex
isti
ng
reu
se
•ar
eas
and
irri
gati
on p
ract
ices
usi
ng
rem
ote
sen
sin
g, w
ater
an
alys
is a
nd
fiel
d su
rvey
s.
Ass
essi
ng
rela
ted
popu
lati
ons
at r
isk
via
•pr
odu
ctio
n fi
gure
s, f
arm
/mar
ket/
reta
il
surv
eys
and
prod
uce
an
alys
is.
Map
pin
g ex
isti
ng
area
s w
her
e •
was
tew
ater
or
poll
ute
d st
ream
wat
er
is u
sed
and
irri
gati
on p
ract
ices
th
rou
gh fi
eld
visi
ts, w
ater
qu
alit
y te
stin
g an
d/or
exp
ert
inte
rvie
ws.
A
sses
sin
g po
pula
tion
s at
ris
k vi
a •
prod
uct
ion
figu
res
and
farm
/mar
ket/
reta
il s
urv
eys.
Qu
anti
fyin
g ri
sks
Wat
er q
ual
ity
to b
e an
alyz
ed
•on
reg
ula
r ti
me
inte
rval
s u
sin
g st
anda
rd la
bora
tory
met
hod
s (m
icro
bial
incl
udi
ng
actu
al
path
ogen
s, a
nd
chem
ical
h
azar
ds).
R
esu
lts
to b
e co
mpa
red
wit
h
•n
atio
nal
wat
er q
ual
ity
stan
dard
s.
Are
as w
ith
con
tam
inat
ion
leve
ls
beyo
nd
tole
rabl
e le
vels
tar
gete
d fo
r in
terv
enti
ons.
Qu
anti
tati
ve M
icro
bial
Ris
k •
Ass
essm
ent
(QM
RA
) an
d Q
uan
tita
tive
Ch
emic
al R
isk
Ass
essm
ent
(QC
RA
) ca
n b
e u
sed
to m
odel
ex-
ante
ris
k sc
enar
ios
for
diff
eren
t w
aste
wat
er
trea
tmen
t ty
pes
and
leve
ls w
hic
h
mig
ht
be a
dju
sted
for
max
imiz
ing
nu
trie
nt
ben
efits
for
agr
icu
ltu
ral
reu
se.
Irri
gati
on w
ater
qu
alit
y sh
ould
be
asse
ssed
•
usi
ng
mic
robi
al a
nd
chem
ical
indi
cato
rs
at p
oin
t of
con
tact
(fa
rm)
in d
ry a
nd
wet
se
ason
; dat
a ob
tain
ed s
hou
ld b
e co
mpa
red
wit
h (
inte
r)n
atio
nal
saf
ety
stan
dard
s.C
rop
part
s to
be
con
sum
ed w
ith
out
•co
okin
g/pe
elin
g sh
ould
be
anal
yzed
for
ac
tual
con
tam
inat
ion
.R
isks
of
alre
ady
expo
sed
farm
com
mu
nit
ies
•ca
n b
e ve
rifi
ed v
ia h
ospi
tal d
ata,
inte
rvie
ws
and/
or e
pide
mio
logi
cal a
nal
ysis
(al
l vs.
co
ntr
ol g
rou
p). Q
MR
A c
ould
pre
dict
ris
ks
of t
he
usu
ally
larg
er c
onsu
mer
gro
up
base
d on
pro
duce
qu
alit
y an
alys
is a
t po
int
of
con
sum
ptio
n. I
n t
he
case
of
epid
emic
s,
mic
robi
al a
nd
epid
emio
logi
cal s
tudi
es c
an
be u
sed
to t
race
an
d ve
rify
th
e so
urc
e.
If la
bora
tori
es a
re a
vail
able
at
leas
t •
key
path
ogen
indi
cato
rs (
feca
l co
lifo
rms,
hel
min
th e
ggs)
sh
ould
be
anal
yzed
in ir
riga
tion
wat
er a
nd
on
irri
gate
d cr
ops.
If
not
, loc
al s
urv
eys
and
obse
rvat
ion
s co
mbi
ned
wit
h
loca
l wat
er u
sers
’ an
d/or
exp
erts
’ kn
owle
dge
cou
ld in
form
wh
eth
er
wat
er is
con
tam
inat
ed w
ith
hu
man
ex
cret
a.
Ris
ks f
or f
arm
ers
cou
ld b
e ve
rifi
ed
•vi
a in
terv
iew
s w
ith
far
mer
s vs
. co
ntr
ol g
rou
p; a
nd
for
farm
ers
at
diff
eren
t lo
cati
ons,
sem
i-qu
anti
fied
vi
a ex
posu
re r
anki
ng.
If f
aeca
l col
ifor
ms
hav
e be
en
•an
alyz
ed, s
impl
e Q
MR
A p
rogr
ams
can
su
ppor
t th
e ri
sk a
sses
smen
t fo
r co
nsu
mer
s.If
wat
er p
ollu
tion
fro
m in
dust
ry
•or
min
ing
is p
ossi
ble,
at
leas
t th
ose
hea
vy m
etal
s w
hic
h a
re li
ttle
ab
sorb
ed in
soi
ls a
nd
gen
eral
ly n
ot
phyt
otox
ic (
e.g.
Cad
miu
m)
shou
ld
be a
nal
yzed
.
OMS-WSHH-Guidance-note1-20100719.indd 4 30/07/10 14:49:42
# 4 # 5
Ste
pA
ctiv
ity
Lev
el o
n t
he
san
itat
ion
lad
der
Hig
her
par
t
(Hig
h-i
nco
me
cou
ntr
ies)
Mid
dle
par
t
(Mid
dle
-in
com
e co
un
trie
s)
Low
er p
art
(Low
-in
com
e co
un
trie
s)
1.S
itu
atio
n
anal
ysis
Map
pin
g ar
eas
and
pra
ctic
esP
lan
ned
reu
se s
chem
es t
o be
•
map
ped
usi
ng
rem
ote
sen
sin
g.R
elat
ed f
arm
ers
and
mar
keti
ng
•en
terp
rise
s to
be
iden
tifi
ed a
nd
regi
ster
ed.
Map
pin
g of
pla
nn
ed o
r ex
isti
ng
reu
se
•ar
eas
and
irri
gati
on p
ract
ices
usi
ng
rem
ote
sen
sin
g, w
ater
an
alys
is a
nd
fiel
d su
rvey
s.
Ass
essi
ng
rela
ted
popu
lati
ons
at r
isk
via
•pr
odu
ctio
n fi
gure
s, f
arm
/mar
ket/
reta
il
surv
eys
and
prod
uce
an
alys
is.
Map
pin
g ex
isti
ng
area
s w
her
e •
was
tew
ater
or
poll
ute
d st
ream
wat
er
is u
sed
and
irri
gati
on p
ract
ices
th
rou
gh fi
eld
visi
ts, w
ater
qu
alit
y te
stin
g an
d/or
exp
ert
inte
rvie
ws.
A
sses
sin
g po
pula
tion
s at
ris
k vi
a •
prod
uct
ion
figu
res
and
farm
/mar
ket/
reta
il s
urv
eys.
Qu
anti
fyin
g ri
sks
Wat
er q
ual
ity
to b
e an
alyz
ed
•on
reg
ula
r ti
me
inte
rval
s u
sin
g st
anda
rd la
bora
tory
met
hod
s (m
icro
bial
incl
udi
ng
actu
al
path
ogen
s, a
nd
chem
ical
h
azar
ds).
R
esu
lts
to b
e co
mpa
red
wit
h
•n
atio
nal
wat
er q
ual
ity
stan
dard
s.
Are
as w
ith
con
tam
inat
ion
leve
ls
beyo
nd
tole
rabl
e le
vels
tar
gete
d fo
r in
terv
enti
ons.
Qu
anti
tati
ve M
icro
bial
Ris
k •
Ass
essm
ent
(QM
RA
) an
d Q
uan
tita
tive
Ch
emic
al R
isk
Ass
essm
ent
(QC
RA
) ca
n b
e u
sed
to m
odel
ex-
ante
ris
k sc
enar
ios
for
diff
eren
t w
aste
wat
er
trea
tmen
t ty
pes
and
leve
ls w
hic
h
mig
ht
be a
dju
sted
for
max
imiz
ing
nu
trie
nt
ben
efits
for
agr
icu
ltu
ral
reu
se.
Irri
gati
on w
ater
qu
alit
y sh
ould
be
asse
ssed
•
usi
ng
mic
robi
al a
nd
chem
ical
indi
cato
rs
at p
oin
t of
con
tact
(fa
rm)
in d
ry a
nd
wet
se
ason
; dat
a ob
tain
ed s
hou
ld b
e co
mpa
red
wit
h (
inte
r)n
atio
nal
saf
ety
stan
dard
s.C
rop
part
s to
be
con
sum
ed w
ith
out
•co
okin
g/pe
elin
g sh
ould
be
anal
yzed
for
ac
tual
con
tam
inat
ion
.R
isks
of
alre
ady
expo
sed
farm
com
mu
nit
ies
•ca
n b
e ve
rifi
ed v
ia h
ospi
tal d
ata,
inte
rvie
ws
and/
or e
pide
mio
logi
cal a
nal
ysis
(al
l vs.
co
ntr
ol g
rou
p). Q
MR
A c
ould
pre
dict
ris
ks
of t
he
usu
ally
larg
er c
onsu
mer
gro
up
base
d on
pro
duce
qu
alit
y an
alys
is a
t po
int
of
con
sum
ptio
n. I
n t
he
case
of
epid
emic
s,
mic
robi
al a
nd
epid
emio
logi
cal s
tudi
es c
an
be u
sed
to t
race
an
d ve
rify
th
e so
urc
e.
If la
bora
tori
es a
re a
vail
able
at
leas
t •
key
path
ogen
indi
cato
rs (
feca
l co
lifo
rms,
hel
min
th e
ggs)
sh
ould
be
anal
yzed
in ir
riga
tion
wat
er a
nd
on
irri
gate
d cr
ops.
If
not
, loc
al s
urv
eys
and
obse
rvat
ion
s co
mbi
ned
wit
h
loca
l wat
er u
sers
’ an
d/or
exp
erts
’ kn
owle
dge
cou
ld in
form
wh
eth
er
wat
er is
con
tam
inat
ed w
ith
hu
man
ex
cret
a.
Ris
ks f
or f
arm
ers
cou
ld b
e ve
rifi
ed
•vi
a in
terv
iew
s w
ith
far
mer
s vs
. co
ntr
ol g
rou
p; a
nd
for
farm
ers
at
diff
eren
t lo
cati
ons,
sem
i-qu
anti
fied
vi
a ex
posu
re r
anki
ng.
If f
aeca
l col
ifor
ms
hav
e be
en
•an
alyz
ed, s
impl
e Q
MR
A p
rogr
ams
can
su
ppor
t th
e ri
sk a
sses
smen
t fo
r co
nsu
mer
s.If
wat
er p
ollu
tion
fro
m in
dust
ry
•or
min
ing
is p
ossi
ble,
at
leas
t th
ose
hea
vy m
etal
s w
hic
h a
re li
ttle
ab
sorb
ed in
soi
ls a
nd
gen
eral
ly n
ot
phyt
otox
ic (
e.g.
Cad
miu
m)
shou
ld
be a
nal
yzed
.
1.S
itu
atio
n
anal
ysis
(ct
nd
)r
isk
p
rior
itiz
atio
n
and
tar
get
sett
ing
Bas
ed o
n a
vail
able
dat
a, r
isks
can
•
be c
lear
ly a
sses
sed,
con
tain
ed
to t
he
wat
er a
nd
tran
slat
ed in
to
requ
ired
tre
atm
ent
capa
city
ta
rget
s.If
for
an
y re
ason
, lik
e n
utr
ien
t •
ben
efits
, tre
atm
ent
wil
l rem
ain
su
bopt
imal
, th
e re
mai
nin
g ri
sk
shou
ld b
e m
itig
ated
th
rou
gh
non
-tre
atm
ent
opti
ons
wh
ich
can
be
con
trol
led
usi
ng
esta
blis
hed
pr
oced
ure
s.
Ris
k re
duct
ion
tar
gets
are
defi
ned
•
via
com
plia
nce
wit
h e
stab
lish
ed
stan
dard
s fo
r ac
cept
able
ris
k pr
obab
ilit
y.
If a
vail
able
mic
robi
al d
ata
exce
ed t
oler
able
•
leve
ls a
nd
can
not
be
con
trol
led
prio
r to
th
e fa
rm e
.g. v
ia w
aste
wat
er t
reat
men
t,
hea
lth
-bas
ed t
arge
ts f
or r
isk
redu
ctio
n w
ill
be s
et a
t th
e po
int
of c
onta
ct (
farm
er)
and
con
sum
ptio
n (
con
sum
er)
to a
llow
for
th
e es
tabl
ish
men
t of
mu
ltip
le b
arri
ers
alon
g th
e fo
od c
hai
n.
Targ
ets
can
be
set
as n
um
ber
of d
iarr
hoe
a •
case
s or
ave
rted
Dis
abil
ity
adju
sted
Lif
e Ye
ars
(DA
LYs)
.B
ased
on
th
e H
AC
CP
app
roac
h, h
azar
ds
•an
d co
ntr
ol p
oin
ts c
an b
e ra
nke
d ta
kin
g ac
cou
nt
of e
xist
ing
con
trol
pra
ctic
es.
For
eac
h c
ontr
ol p
oin
t a
mon
itor
ing
targ
et
•sh
ould
be
set
join
tly
by h
ealt
h o
ffici
als,
fa
rmer
s, p
rodu
ce s
elle
rs e
tc.
Far
m lo
cati
ons
nea
r li
kely
ch
emic
al
•co
nta
min
atio
n s
ourc
es s
hou
ld r
ecei
ve h
igh
at
ten
tion
.
Bas
ed o
n a
vail
able
dat
a, r
isks
can
•
be r
anke
d fo
r di
ffer
ent
expo
sed
popu
lati
ons
usi
ng
mu
lti-
crit
eria
an
alys
is o
f th
eir
expo
sure
leve
l (c
onta
ct, i
nta
ke, f
requ
ency
). T
his
co
uld
be
don
e w
ith
con
cern
ed
stak
ehol
ders
su
ch a
s h
ealt
h o
ffici
als,
fa
rmer
s an
d pr
odu
ce s
elle
rs a
nd
shou
ld a
llow
for
pri
orit
y se
ttin
g.In
terv
enti
on t
arge
ts s
hou
ld b
e •
real
isti
c an
d m
easu
rabl
e. S
impl
e ex
ampl
es a
re t
he
perc
enta
ge o
f re
duce
d di
arrh
ea c
ases
, or
leve
ls
of lo
g re
duct
ion
s of
fec
al c
olif
orm
s fr
om s
ourc
e to
leve
l of
prod
uce
co
nsu
mpt
ion
(as
sum
ing
irri
gati
on is
n
ot r
estr
icte
d an
d pr
odu
ce is
eat
en
raw
).F
arm
loca
tion
s n
ear
poss
ible
•
chem
ical
con
tam
inat
ion
sou
rces
sh
ould
rec
eive
par
ticu
lar
atte
nti
on
(see
bel
ow).
2. i
den
tifi
cati
on
and
val
idat
ion
of
ris
k r
edu
ctio
n
mea
sure
s
iden
tifi
cati
on o
f ri
sk r
edu
ctio
n
mea
sure
s
Was
tew
ater
tre
atm
ent
has
pro
ven
•
to b
e ve
ry r
elia
ble
and
is a
pr
iori
ty r
isk
redu
ctio
n m
easu
re.
For
an
y re
mai
nin
g ri
sk, n
on-
trea
tmen
t op
tion
s w
ill b
e ap
plie
d u
sin
g th
e H
AC
CP
app
roac
h w
ith
ag
reed
sta
nda
rds.
Mea
sure
s m
igh
t in
clu
de: p
re-
•fa
rm -
con
ven
tion
al w
aste
wat
er
trea
tmen
t to
ter
tiar
y le
vel;
at f
arm
-
use
of
subs
urf
ace
drip
irri
gati
on
syst
ems,
cro
p re
stri
ctio
n,
and
occu
pati
onal
pro
tect
ion
m
easu
res.
Pos
t-h
arve
st r
e-co
nta
min
atio
n
•ri
sk is
ass
um
ed t
o be
un
der
con
trol
an
d m
onit
ored
by
stan
dard
foo
d sa
fety
an
d h
ygie
ne
prot
ocol
s; i.
e. n
on-t
reat
men
t in
terv
enti
ons
also
app
ly h
ere.
Exp
lore
if a
lter
nat
ive
lan
d an
d w
ater
•
reso
urc
es a
re a
vail
able
for
far
mer
s co
nce
rned
.E
xplo
re w
ith
sta
keh
olde
rs c
once
rned
th
e •
curr
ent
trea
tmen
t st
anda
rds
ups
trea
m
of f
arm
ing
area
s, a
nd
non
-tre
atm
ent
safe
ty p
ract
ices
at
pre-
farm
, on
-far
m a
nd
post
-far
m le
vels
, as
wel
l as
opti
ons
for
opti
miz
ing
them
in a
last
ing
way
. M
easu
res
for
risk
red
uct
ion
cou
ld
•in
clu
de, a
t pr
e-fa
rm, w
aste
wat
er t
reat
men
t (u
pgra
de)
to s
econ
dary
leve
l; at
far
ms,
dri
p ir
riga
tion
an
d oc
cupa
tion
al s
afet
y m
easu
res;
po
st-h
arve
st, e
nsu
re s
anit
ary
con
diti
ons
in
mar
kets
an
d fo
od s
elli
ng
poin
ts, e
tc.
En
forc
e ex
isti
ng
food
saf
ety
regu
lati
ons
and
•st
anda
rds.
Pla
n f
or a
ppro
pria
te w
aste
wat
er
•tr
eatm
ent
ups
trea
m o
f fa
rmin
g si
tes
taki
ng
into
acc
oun
t th
e ab
sorp
tion
ca
paci
ty o
f th
e re
ceiv
ing
wat
er b
ody.
Exp
lore
wh
eth
er a
lter
nat
ive
lan
d •
and
(gro
un
d) w
ater
res
ourc
es a
re
avai
labl
e fo
r fa
rmer
s, a
nd
if n
ot f
ocu
s on
non
-tre
atm
ent
opti
ons.
Id
enti
fy r
eali
stic
inte
rven
tion
s •
wit
h r
elev
ant
stak
ehol
ders
un
der
con
side
rati
on o
f av
aila
ble
fun
ds,
reli
abil
ity,
cos
t-ef
fect
iven
ess,
an
d ad
opti
on p
oten
tial
. For
exa
mpl
e:
pre-
farm
- s
ome
wat
er t
reat
men
t to
pr
imar
y le
vel u
sin
g po
nd
syst
ems;
at
farm
- u
sin
g si
mpl
e se
dim
enta
tion
po
nds
, dri
p ir
riga
tion
kit
s; p
ost-
har
vest
- u
sin
g m
ore
effe
ctiv
e ve
geta
ble
was
hin
g m
eth
ods,
wh
ich
in
var
iou
s re
alis
tic
com
bin
atio
ns
ach
ieve
th
e re
quir
ed r
isk
redu
ctio
n.
Supp
ort
edu
cati
onal
eff
orts
on
th
e •
nee
d to
min
imiz
e oc
cupa
tion
al
wat
er c
onta
ct w
hil
e m
ain
tain
ing
appr
opri
ate
hyg
ien
e af
ter
wor
k.
OMS-WSHH-Guidance-note1-20100719.indd 5 30/07/10 14:49:42
# 6 # 7
Ste
pA
ctiv
ity
Lev
el o
n t
he
san
itat
ion
lad
der
Hig
her
par
t
(Hig
h-i
nco
me
cou
ntr
ies)
Mid
dle
par
t
(Mid
dle
-in
com
e co
un
trie
s)
Low
er p
art
(Low
-in
com
e co
un
trie
s)
2. i
den
tifi
cati
on
and
val
idat
ion
of
ris
k r
edu
ctio
n
mea
sure
s (c
tnd
)
Val
idat
ion
of
sugg
este
d m
easu
res
Trea
tmen
t pl
ant
effl
uen
t •
mon
itor
ing.
Pil
ot p
has
e w
ith
•
acco
mpa
nyi
ng
rese
arch
to
mon
itor
th
e im
pact
of
rec
omm
ende
d fa
rm
prac
tice
s.F
or la
bora
tory
an
alys
is,
•u
se s
peci
fic
path
ogen
s an
d ch
emic
al p
aram
eter
s as
sp
elle
d ou
t in
sta
nda
rds.
If u
pgra
ded/
con
stru
cted
was
tew
ater
•
trea
tmen
t fa
cili
ties
wil
l geo
grap
hic
ally
in
flu
ence
irri
gati
on w
ater
qu
alit
y,
impl
emen
t ef
flu
ent
mon
itor
ing.
Pil
ot p
has
e w
ith
acc
ompa
nyi
ng
rese
arch
to
•m
onit
or t
he
effi
cacy
an
d lo
cal a
ccep
tan
ce
of r
ecom
men
ded
non
-tre
atm
ent
opti
ons
usi
ng
a co
mbi
nat
ion
of
inte
rvie
ws,
fiel
d an
d la
bora
tory
tes
tin
g.F
or a
sses
smen
t, u
se s
tan
dard
par
amet
ers,
•
both
mic
robi
olog
ical
an
d ch
emic
al.
If u
pgra
ded/
con
stru
cted
•
was
tew
ater
tre
atm
ent
faci
liti
es w
ill
geog
raph
ical
ly in
flu
ence
irri
gati
on
wat
er q
ual
ity,
impl
emen
t ef
flu
ent
mon
itor
ing.
Pil
ot p
has
e of
acc
ompa
nyi
ng
•pa
rtic
ipat
ory
rese
arch
to
mu
tual
ly
un
ders
tan
d an
d im
prov
e th
e ef
fica
cy a
nd
loca
l ado
ptio
n o
f re
com
men
ded
non
-tre
atm
ent
opti
ons.
F
or a
sses
smen
t, u
se s
ocia
l, •
econ
omic
, an
d m
icro
biol
ogic
al
labo
rato
ry a
nal
ysis
as
wel
l as
qual
itat
ive
met
hod
s (o
bser
vati
ons,
in
terv
iew
s) a
nd
any
mea
ns
to
visu
aliz
e th
e in
visi
ble
(mic
robi
al)
risk
.
3. i
mp
lem
enta
tion
of
mea
sure
sD
evel
opin
g p
lan
Shou
ld f
ollo
w e
stab
lish
ed
•pr
acti
ces
and
regu
lati
ons
invo
lvin
g al
l con
cern
ed
stak
ehol
ders
.
Dev
elop
an
inte
grat
ed r
isk
mit
igat
ion
pla
n
•co
mbi
nin
g tr
eatm
ent
and
non
-tre
atm
ent
opti
ons.
Th
e co
mbi
ned
app
roac
h r
equ
ires
a
focu
s on
defi
ned
hyd
rolo
gica
l cat
chm
ent
area
s w
her
e w
ater
tre
atm
ent
affe
cts
the
wat
er fl
owin
g to
th
e co
nce
rned
far
min
g si
tes
and
- if
pos
sibl
e -
defi
ned
(is
olat
ed)
prod
uce
mar
keti
ng
chan
nel
s fo
r w
aste
wat
er
irri
gate
d pr
odu
ce.
Exp
lore
opt
ion
s to
su
stai
n a
dopt
ion
of
•n
on-t
reat
men
t op
tion
s vi
a in
cen
tive
s, s
ocia
l m
arke
tin
g, r
egu
lati
ons/
fees
etc
. alo
ng
the
farm
to
fork
pat
hw
ay.
Dev
elop
an
inte
grat
ed r
isk
•m
itig
atio
n p
lan
wit
h a
ll c
once
rned
st
akeh
olde
rs w
ith
em
phas
is o
n
awar
enes
s cr
eati
on, e
duca
tion
an
d n
on-t
reat
men
t op
tion
s.
Ext
end
safe
ty m
easu
res
to a
ll
•ir
riga
ted
crop
s, a
s fo
r th
ose
prod
uce
d w
ith
was
tew
ater
if
mar
keti
ng
chan
nel
s ca
n n
ot b
e se
para
ted
for
safe
an
d u
nsa
fe
prod
uce
. E
xten
d ri
sk r
edu
ctio
n m
easu
res
•to
add
ress
foo
d sa
fety
an
d h
ygie
ne
in g
ener
al, i
f ri
sk o
f po
st-h
arve
st
con
tam
inat
ion
is h
igh
.
Act
ual
im
ple
men
tati
on/
dis
sem
inat
ion
Wit
h w
aste
wat
er t
reat
men
t •
in p
lace
, non
-tre
atm
ent
opti
ons
wil
l be
equ
ally
wel
l re
gula
ted
and
mon
itor
ed.
Such
opt
ion
s sh
ould
als
o •
shou
ld b
e in
corp
orat
ed in
to
edu
cati
onal
pro
gram
mes
an
d tr
ain
ing
curr
icu
la.
Lim
it w
aste
wat
er ir
riga
tion
to
thos
e •
loca
tion
s (c
atch
men
ts)
wit
h u
pstr
eam
w
aste
wat
er t
reat
men
t.
Lim
it w
aste
wat
er ir
riga
ted
prod
uce
to
•th
ose
farm
-to-
fork
pat
hw
ays
wh
ere
safe
ty
mea
sure
s su
ppor
t ea
ch-o
ther
.In
volv
e br
oad
ran
ge o
f st
akeh
olde
rs.
•
Impl
emen
t a
beh
avio
r ch
ange
•
cam
paig
n, b
ased
on
ince
nti
ves,
so
cial
mar
keti
ng
(val
ues
),
regu
lati
ons
and
edu
cati
on t
o fa
cili
tate
a la
stin
g ad
opti
on o
f n
on-
trea
tmen
t op
tion
s.
OMS-WSHH-Guidance-note1-20100719.indd 6 30/07/10 14:49:42
# 6 # 7
Ste
pA
ctiv
ity
Lev
el o
n t
he
san
itat
ion
lad
der
Hig
her
par
t
(Hig
h-i
nco
me
cou
ntr
ies)
Mid
dle
par
t
(Mid
dle
-in
com
e co
un
trie
s)
Low
er p
art
(Low
-in
com
e co
un
trie
s)
2. i
den
tifi
cati
on
and
val
idat
ion
of
ris
k r
edu
ctio
n
mea
sure
s (c
tnd
)
Val
idat
ion
of
sugg
este
d m
easu
res
Trea
tmen
t pl
ant
effl
uen
t •
mon
itor
ing.
Pil
ot p
has
e w
ith
•
acco
mpa
nyi
ng
rese
arch
to
mon
itor
th
e im
pact
of
rec
omm
ende
d fa
rm
prac
tice
s.F
or la
bora
tory
an
alys
is,
•u
se s
peci
fic
path
ogen
s an
d ch
emic
al p
aram
eter
s as
sp
elle
d ou
t in
sta
nda
rds.
If u
pgra
ded/
con
stru
cted
was
tew
ater
•
trea
tmen
t fa
cili
ties
wil
l geo
grap
hic
ally
in
flu
ence
irri
gati
on w
ater
qu
alit
y,
impl
emen
t ef
flu
ent
mon
itor
ing.
Pil
ot p
has
e w
ith
acc
ompa
nyi
ng
rese
arch
to
•m
onit
or t
he
effi
cacy
an
d lo
cal a
ccep
tan
ce
of r
ecom
men
ded
non
-tre
atm
ent
opti
ons
usi
ng
a co
mbi
nat
ion
of
inte
rvie
ws,
fiel
d an
d la
bora
tory
tes
tin
g.F
or a
sses
smen
t, u
se s
tan
dard
par
amet
ers,
•
both
mic
robi
olog
ical
an
d ch
emic
al.
If u
pgra
ded/
con
stru
cted
•
was
tew
ater
tre
atm
ent
faci
liti
es w
ill
geog
raph
ical
ly in
flu
ence
irri
gati
on
wat
er q
ual
ity,
impl
emen
t ef
flu
ent
mon
itor
ing.
Pil
ot p
has
e of
acc
ompa
nyi
ng
•pa
rtic
ipat
ory
rese
arch
to
mu
tual
ly
un
ders
tan
d an
d im
prov
e th
e ef
fica
cy a
nd
loca
l ado
ptio
n o
f re
com
men
ded
non
-tre
atm
ent
opti
ons.
F
or a
sses
smen
t, u
se s
ocia
l, •
econ
omic
, an
d m
icro
biol
ogic
al
labo
rato
ry a
nal
ysis
as
wel
l as
qual
itat
ive
met
hod
s (o
bser
vati
ons,
in
terv
iew
s) a
nd
any
mea
ns
to
visu
aliz
e th
e in
visi
ble
(mic
robi
al)
risk
.
3. i
mp
lem
enta
tion
of
mea
sure
sD
evel
opin
g p
lan
Shou
ld f
ollo
w e
stab
lish
ed
•pr
acti
ces
and
regu
lati
ons
invo
lvin
g al
l con
cern
ed
stak
ehol
ders
.
Dev
elop
an
inte
grat
ed r
isk
mit
igat
ion
pla
n
•co
mbi
nin
g tr
eatm
ent
and
non
-tre
atm
ent
opti
ons.
Th
e co
mbi
ned
app
roac
h r
equ
ires
a
focu
s on
defi
ned
hyd
rolo
gica
l cat
chm
ent
area
s w
her
e w
ater
tre
atm
ent
affe
cts
the
wat
er fl
owin
g to
th
e co
nce
rned
far
min
g si
tes
and
- if
pos
sibl
e -
defi
ned
(is
olat
ed)
prod
uce
mar
keti
ng
chan
nel
s fo
r w
aste
wat
er
irri
gate
d pr
odu
ce.
Exp
lore
opt
ion
s to
su
stai
n a
dopt
ion
of
•n
on-t
reat
men
t op
tion
s vi
a in
cen
tive
s, s
ocia
l m
arke
tin
g, r
egu
lati
ons/
fees
etc
. alo
ng
the
farm
to
fork
pat
hw
ay.
Dev
elop
an
inte
grat
ed r
isk
•m
itig
atio
n p
lan
wit
h a
ll c
once
rned
st
akeh
olde
rs w
ith
em
phas
is o
n
awar
enes
s cr
eati
on, e
duca
tion
an
d n
on-t
reat
men
t op
tion
s.
Ext
end
safe
ty m
easu
res
to a
ll
•ir
riga
ted
crop
s, a
s fo
r th
ose
prod
uce
d w
ith
was
tew
ater
if
mar
keti
ng
chan
nel
s ca
n n
ot b
e se
para
ted
for
safe
an
d u
nsa
fe
prod
uce
. E
xten
d ri
sk r
edu
ctio
n m
easu
res
•to
add
ress
foo
d sa
fety
an
d h
ygie
ne
in g
ener
al, i
f ri
sk o
f po
st-h
arve
st
con
tam
inat
ion
is h
igh
.
Act
ual
im
ple
men
tati
on/
dis
sem
inat
ion
Wit
h w
aste
wat
er t
reat
men
t •
in p
lace
, non
-tre
atm
ent
opti
ons
wil
l be
equ
ally
wel
l re
gula
ted
and
mon
itor
ed.
Such
opt
ion
s sh
ould
als
o •
shou
ld b
e in
corp
orat
ed in
to
edu
cati
onal
pro
gram
mes
an
d tr
ain
ing
curr
icu
la.
Lim
it w
aste
wat
er ir
riga
tion
to
thos
e •
loca
tion
s (c
atch
men
ts)
wit
h u
pstr
eam
w
aste
wat
er t
reat
men
t.
Lim
it w
aste
wat
er ir
riga
ted
prod
uce
to
•th
ose
farm
-to-
fork
pat
hw
ays
wh
ere
safe
ty
mea
sure
s su
ppor
t ea
ch-o
ther
.In
volv
e br
oad
ran
ge o
f st
akeh
olde
rs.
•
Impl
emen
t a
beh
avio
r ch
ange
•
cam
paig
n, b
ased
on
ince
nti
ves,
so
cial
mar
keti
ng
(val
ues
),
regu
lati
ons
and
edu
cati
on t
o fa
cili
tate
a la
stin
g ad
opti
on o
f n
on-
trea
tmen
t op
tion
s.
3. i
mp
lem
enta
tion
of
mea
sure
s (c
tnd
)A
ctu
al
imp
lem
enta
tion
/ d
isse
min
atio
n
(ctn
d)
Use
med
ia a
nd
soci
al m
arke
tin
g to
su
ppor
t •
beh
avio
r ch
ange
tow
ards
non
-tre
atm
ent
opti
ons.
Reg
ula
te c
hem
ical
con
tam
inan
ts a
nd
•im
prov
e (s
ourc
e) t
reat
men
t fa
cili
ties
an
d ti
ll t
hen
ban
rel
ated
was
tew
ater
use
.
Far
mer
s in
are
as w
ith
hig
h
•pr
obab
ilit
y of
ch
emic
al
con
tam
inat
ion
sh
ould
be
supp
orte
d to
far
m e
lsew
her
e. T
he
site
s sh
ould
be
clo
sed
un
til p
ollu
tion
sou
rces
h
ave
been
iden
tifi
ed a
nd
con
trol
led.
4.O
per
atio
nal
m
onit
orin
gD
evel
op p
lan
Shou
ld f
ollo
w e
stab
lish
ed
•re
gula
tion
s by
cer
tifi
ed
inst
itu
tion
s/go
vern
men
tal
agen
cies
/lab
orat
orie
s in
th
e w
ater
an
d fo
od s
ecto
r/in
dust
ry.
Can
be
adap
ted
to lo
cal m
onit
orin
g pl
an
•of
on
goin
g pr
ogra
ms
rela
ted
to f
ood
safe
ty,
publ
ic h
ealt
h a
nd
wat
er p
ollu
tion
.Sh
ould
hav
e in
spec
tion
sta
nda
rds
or
•an
alyt
ical
indi
cato
rs t
o be
adh
ered
to.
Dev
elop
mon
itor
ing
plan
wit
h
•re
leva
nt
stak
ehol
ders
. F
ocu
s on
sim
ple
indi
cato
rs a
nd
•pr
oxie
s.
En
cou
rage
loca
l res
earc
h
•in
stit
uti
ons
to g
et in
volv
ed in
sy
stem
atic
ope
rati
onal
mon
itor
ing.
Act
ual
mon
itor
ing
of c
omp
lian
ceF
ollo
ws
esta
blis
hed
•
insp
ecti
on a
nd
sam
plin
g pr
otoc
ols
wit
h in
depe
nde
nt
con
trol
/au
dit.
N
on-c
ompl
ian
ce s
hou
ld
•le
ad t
o le
gal i
mpl
icat
ion
s an
d ap
prop
riat
e fe
es.
Shou
ld b
e do
ne
by w
hic
hev
er e
nti
ty t
hat
•
can
mos
t re
liab
ly m
onit
or: g
over
nm
ent
inst
itu
tion
s, e
nvi
ron
men
tal p
rote
ctio
n
agen
cy o
r pr
ivat
e se
ctor
. N
on-c
ompl
ian
ce s
hou
ld h
ave
lega
l •
impl
icat
ion
s an
d ap
prop
riat
e fe
es
Impl
emen
ters
(fa
rmer
s, v
eget
able
•
and
food
sel
lers
) sh
ould
be
empo
wer
ed t
hro
ugh
tra
inin
g to
do
(an
d u
nde
rsta
nd
the
valu
e of
) se
lf-
mon
itor
ing.
At
leas
t ra
ndo
m in
spec
tion
by
•au
thor
itie
s (r
isk
of f
rau
d to
be
addr
esse
d).
Mon
itor
ing
shou
ld b
e ba
sed
on
•si
mpl
e an
d ra
pid
obse
rvat
ion
s, li
ke
phys
ical
indi
cato
rs s
uch
as
colo
r,
smel
l etc
.
5.V
erifi
cati
onVer
ify
if s
et t
arge
ts
are
ach
ieve
dF
ollo
ws
esta
blis
hed
•
prot
ocol
s of
mic
robi
al a
nd
chem
ical
ris
k an
alys
is.
Shou
ld v
erif
y if
th
e va
riou
s ri
sk b
arri
ers
•ac
tual
ly a
chie
ve t
he
pre-
defi
ned
hea
lth
-ba
sed
targ
ets
(e.g
. red
uct
ion
in d
iarr
hoe
a ca
ses
or D
ALY
in t
arge
t po
pula
tion
s).
Shou
ld v
erif
y if
com
bin
atio
ns
of
•th
e va
riou
s ri
sk b
arri
ers
ach
ieve
th
e pr
e-de
fin
ed (
see
abov
e) h
ealt
h-
base
d ta
rget
s li
ke r
edu
ctio
n in
n
um
ber
of d
iarr
hoe
a ca
ses.
OMS-WSHH-Guidance-note1-20100719.indd 7 30/07/10 14:49:43
# 8 # 9
TA
BL
E 3
A.
Exa
mpl
e of
hea
lth
-bas
ed t
arge
ts in
cou
ntr
ies
at d
iffe
ren
t le
vels
on
th
e sa
nit
atio
n la
dder
Lev
el o
n t
he
san
itat
ion
lad
der
Hig
her
par
t(H
igh
-in
com
e co
un
trie
s)M
idd
le p
art
(Mid
dle
-in
com
e co
un
trie
s)L
ower
par
t(L
ow-i
nco
me
cou
ntr
ies)
Typ
e of
tar
get
(exa
mpl
es
per
cou
ntr
y gr
oup)
Hea
lth
ou
tcom
e ta
rget
s•
Wat
er a
nd
food
qu
alit
y ta
rget
s•
Tech
nic
al t
arge
ts•
Wat
er a
nd
food
qu
alit
y ta
rget
s•
Per
form
ance
/tec
hn
ical
tar
get
•W
ater
an
d fo
od q
ual
ity
targ
ets
•P
erfo
rman
ce t
arge
ts•
TA
BL
E 3
B.
Ch
arac
teri
stic
s of
dif
fere
nt
hea
lth
-bas
ed t
arge
ts
Hea
lth
ou
tcom
e ta
rget
sW
ater
an
d f
ood
qu
alit
y ta
rget
sP
erfo
rman
ce/t
ech
nic
al t
arge
ts
Nat
ure
of
targ
etD
efin
ed t
oler
able
bu
rden
of
dise
ase
(max
imu
m
freq
uen
cy o
f di
seas
e)L
ow-
or n
o-ri
sk t
hre
shol
ds f
or c
hem
ical
s or
pat
hog
en in
dica
tors
usu
ally
bas
ed o
n
inte
rnat
ion
al g
uid
elin
es
Ris
k re
duct
ion
tar
gets
per
non
-tre
atm
ent
inte
rven
tion
or
trea
tmen
t te
chn
olog
y
Typ
ical
ap
pli
cati
onH
igh
-lev
el p
olic
y ta
rget
s e.
g. f
or r
estr
icte
d an
d u
nre
stri
cted
irri
gati
on, o
r ty
pe o
f cr
op; b
est
expr
esse
d in
DA
LY p
er p
erso
n a
nd
year
as
this
all
ows
the
corr
espo
ndi
ngl
y re
quir
ed r
isk
redu
ctio
n t
o be
defi
ned
Com
mon
mon
itor
ing
guid
elin
e va
lues
. N
atio
nal
ada
ptat
ion
req
uir
es q
uan
tita
tive
ris
k as
sess
men
t ba
sed
on e
xpos
ure
an
d ac
cept
able
in
take
.
Bas
ed o
n a
chie
vabl
e ri
sk r
edu
ctio
n, e
.g.
expr
esse
d as
E. c
oli l
og-u
nit
red
uct
ion
, or
perc
enta
ge r
edu
ctio
n o
f ch
emic
al in
dica
tors
Dat
a n
eed
s an
d/
or c
omp
lexi
ty o
f m
onit
orin
g
Hig
h
Med
ium
Low
Ada
ptin
g th
e ap
proa
ch o
f the
WH
O G
uide
line
s on
Dri
nki
ng-w
ater
Qu
alit
y, T
able
3 d
escr
ibes
pos
sibl
e he
alth
-bas
ed ta
rget
s: (i
) m
easu
rabl
e he
alth
obj
ecti
ves,
(ii)
wat
er q
ual
ity
or
food
qu
alit
y th
resh
olds
, (ii
i) in
terv
enti
on p
erfo
rman
ce ta
rget
s, a
nd (v
) te
chno
logy
rel
ated
sta
ndar
ds. A
ll ta
rget
s sh
ould
be
base
d on
a ju
dgm
ent o
f the
req
uire
d sa
fety
and
on
risk
asse
ssm
ent.
The
trad
itio
nal
ly p
refe
rred
tar
gets
are
wat
er q
ual
ity
thre
shol
d va
lues
, wh
ich
prov
ide
a si
mpl
e be
nch
mar
k; h
owev
er, w
here
tech
nic
al th
resh
olds
can
not
be
ach
ieve
d
or m
aint
aine
d, o
r w
here
ach
ievi
ng th
em w
ould
not
ch
ange
the
actu
al r
isk
(for
exa
mpl
e w
here
hig
hly
trea
ted
efflu
ent e
nter
s a
larg
er u
ntre
ated
was
tew
ater
str
eam
) th
ey w
ill o
nly
cost
mon
ey b
ut n
ot s
afeg
uar
d pu
blic
hea
lth.
Tar
gets
sho
uld
thu
s be
rea
list
ic a
nd r
elev
ant
to lo
cal c
ondi
tion
s (c
onsi
deri
ng fo
r ex
ampl
e. t
he r
ecei
ving
wat
er b
ody’
s qu
alit
y an
d
abso
rpti
on c
apac
ity)
and
fin
anci
al, t
ech
nic
al a
nd in
stit
utio
nal
res
ourc
es. W
ith
incr
easi
ng o
ptio
ns
and
reso
urce
s, t
arge
ts c
an b
e pr
ogre
ssiv
ely
adju
sted
. In
man
y si
tuat
ion
s th
ere
are
adva
ntag
es to
ach
ievi
ng t
he t
arge
ts t
hro
ugh
diff
eren
t but
com
plem
enta
ry in
terv
enti
ons
alon
g th
e co
ntam
inat
ion
path
way
(m
ulti
ple
barr
ier
appr
oach
). H
ealt
h-ba
sed
targ
ets
shou
ld a
lso
con
side
r th
e w
ider
con
text
of r
isk,
esp
ecia
lly in
low
-inc
ome
coun
trie
s, w
here
was
tew
ater
irri
gate
d fo
od is
on
ly o
ne o
f sev
eral
ris
k fa
ctor
s. I
n th
ese
case
s, t
he c
ost-
effe
ctiv
enes
s of
dif
fere
nt in
terv
enti
ons
addr
essi
ng d
iffe
rent
ris
k fa
ctor
s sh
ould
be
com
pare
d.
OMS-WSHH-Guidance-note1-20100719.indd 8 30/07/10 14:49:43
# 8 # 9
Lev
el o
n t
he
san
itat
ion
lad
der
Hig
her
par
t(H
igh
-in
com
e co
un
trie
s)M
idd
le p
art
(Mid
dle
-in
com
e co
un
trie
s)L
ower
par
t(L
ow-i
nco
me
cou
ntr
ies)
Typ
e of
tar
get
(exa
mpl
es
per
cou
ntr
y gr
oup)
Hea
lth
ou
tcom
e ta
rget
s•
Wat
er a
nd
food
qu
alit
y ta
rget
s•
Tech
nic
al t
arge
ts•
Wat
er a
nd
food
qu
alit
y ta
rget
s•
Per
form
ance
/tec
hn
ical
tar
get
•W
ater
an
d fo
od q
ual
ity
targ
ets
•P
erfo
rman
ce t
arge
ts•
Hea
lth
ou
tcom
e ta
rget
sW
ater
an
d f
ood
qu
alit
y ta
rget
sP
erfo
rman
ce/t
ech
nic
al t
arge
ts
Nat
ure
of
targ
etD
efin
ed t
oler
able
bu
rden
of
dise
ase
(max
imu
m
freq
uen
cy o
f di
seas
e)L
ow-
or n
o-ri
sk t
hre
shol
ds f
or c
hem
ical
s or
pat
hog
en in
dica
tors
usu
ally
bas
ed o
n
inte
rnat
ion
al g
uid
elin
es
Ris
k re
duct
ion
tar
gets
per
non
-tre
atm
ent
inte
rven
tion
or
trea
tmen
t te
chn
olog
y
Typ
ical
ap
pli
cati
onH
igh
-lev
el p
olic
y ta
rget
s e.
g. f
or r
estr
icte
d an
d u
nre
stri
cted
irri
gati
on, o
r ty
pe o
f cr
op; b
est
expr
esse
d in
DA
LY p
er p
erso
n a
nd
year
as
this
all
ows
the
corr
espo
ndi
ngl
y re
quir
ed r
isk
redu
ctio
n t
o be
defi
ned
Com
mon
mon
itor
ing
guid
elin
e va
lues
. N
atio
nal
ada
ptat
ion
req
uir
es q
uan
tita
tive
ris
k as
sess
men
t ba
sed
on e
xpos
ure
an
d ac
cept
able
in
take
.
Bas
ed o
n a
chie
vabl
e ri
sk r
edu
ctio
n, e
.g.
expr
esse
d as
E. c
oli l
og-u
nit
red
uct
ion
, or
perc
enta
ge r
edu
ctio
n o
f ch
emic
al in
dica
tors
Dat
a n
eed
s an
d/
or c
omp
lexi
ty o
f m
onit
orin
g
Hig
h
Med
ium
Low
Ada
ptin
g th
e ap
proa
ch o
f the
WH
O G
uide
line
s on
Dri
nki
ng-w
ater
Qu
alit
y, T
able
3 d
escr
ibes
pos
sibl
e he
alth
-bas
ed ta
rget
s: (i
) m
easu
rabl
e he
alth
obj
ecti
ves,
(ii)
wat
er q
ual
ity
or
food
qu
alit
y th
resh
olds
, (ii
i) in
terv
enti
on p
erfo
rman
ce ta
rget
s, a
nd (v
) te
chno
logy
rel
ated
sta
ndar
ds. A
ll ta
rget
s sh
ould
be
base
d on
a ju
dgm
ent o
f the
req
uire
d sa
fety
and
on
risk
asse
ssm
ent.
The
trad
itio
nal
ly p
refe
rred
tar
gets
are
wat
er q
ual
ity
thre
shol
d va
lues
, wh
ich
prov
ide
a si
mpl
e be
nch
mar
k; h
owev
er, w
here
tech
nic
al th
resh
olds
can
not
be
ach
ieve
d
or m
aint
aine
d, o
r w
here
ach
ievi
ng th
em w
ould
not
ch
ange
the
actu
al r
isk
(for
exa
mpl
e w
here
hig
hly
trea
ted
efflu
ent e
nter
s a
larg
er u
ntre
ated
was
tew
ater
str
eam
) th
ey w
ill o
nly
cost
mon
ey b
ut n
ot s
afeg
uar
d pu
blic
hea
lth.
Tar
gets
sho
uld
thu
s be
rea
list
ic a
nd r
elev
ant
to lo
cal c
ondi
tion
s (c
onsi
deri
ng fo
r ex
ampl
e. t
he r
ecei
ving
wat
er b
ody’
s qu
alit
y an
d
abso
rpti
on c
apac
ity)
and
fin
anci
al, t
ech
nic
al a
nd in
stit
utio
nal
res
ourc
es. W
ith
incr
easi
ng o
ptio
ns
and
reso
urce
s, t
arge
ts c
an b
e pr
ogre
ssiv
ely
adju
sted
. In
man
y si
tuat
ion
s th
ere
are
adva
ntag
es to
ach
ievi
ng t
he t
arge
ts t
hro
ugh
diff
eren
t but
com
plem
enta
ry in
terv
enti
ons
alon
g th
e co
ntam
inat
ion
path
way
(m
ulti
ple
barr
ier
appr
oach
). H
ealt
h-ba
sed
targ
ets
shou
ld a
lso
con
side
r th
e w
ider
con
text
of r
isk,
esp
ecia
lly in
low
-inc
ome
coun
trie
s, w
here
was
tew
ater
irri
gate
d fo
od is
on
ly o
ne o
f sev
eral
ris
k fa
ctor
s. I
n th
ese
case
s, t
he c
ost-
effe
ctiv
enes
s of
dif
fere
nt in
terv
enti
ons
addr
essi
ng d
iffe
rent
ris
k fa
ctor
s sh
ould
be
com
pare
d.
TA
BL
E 4
. E
xam
ples
of
com
mon
was
tew
ater
tre
atm
ent
opti
ons
by s
cale
of
irri
gati
on a
nd
leve
l of
econ
omic
de
velo
pmen
t1
Ch
arac
teri
stic
s H
igh
-in
com
e co
un
trie
sM
idd
le-i
nco
me
cou
ntr
ies
Low
-in
com
e co
un
trie
s
Sca
le o
f in
terv
enti
ons
a)
Hou
seh
olds
wit
h g
arde
nb)
Sm
all-
scal
e co
mm
un
al p
lots
nea
r po
llu
ted
stre
ams
and
drai
ns
c)
Lar
ger
urb
an o
r pe
ri-u
rban
plo
ts n
ext
to d
ecen
tral
ized
sim
plifi
ed s
ewer
age
syst
ems
d)
Lar
ger
peri
-urb
an p
lots
wit
h c
ity-
wid
e se
wer
age
syst
em
Typ
ical
tre
atm
ent
tech
nol
ogy
opti
ons
per
sc
ale
(exa
mp
les)
1
Hou
seh
olds
wit
h g
arde
n:
Sew
erag
e•
Dry
toi
lets
, uri
ne
coll
ecti
on, a
nd
•gr
eyw
ater
sep
arat
ion
an
d tr
eatm
ent
Com
mu
nal
or
mu
nic
ipal
far
min
g ar
eas
of a
ny
size
:C
onve
nti
onal
tre
atm
ent
+ te
rtia
ry
•tr
eatm
ent
Mem
bran
e te
chn
olog
ies
•So
il a
quif
er t
reat
men
t (S
AT)
syst
ems
•w
her
e po
ssib
leIn
dust
rial
sou
rce
trea
tmen
t•
Hou
seh
olds
wit
h g
arde
n:
Sept
ic t
anks
•Im
hof
f ta
nk
•O
n-s
ite
grey
wat
er t
reat
men
t• C
omm
un
al p
lots
:P
rim
ary
trea
tmen
t +
con
stru
cted
wet
lan
ds• L
arge
plo
ts o
r m
ediu
m-s
ize
city
:W
aste
sta
bili
zati
on p
ond
syst
ems
•D
ecen
tral
ized
was
tew
ater
tre
atm
ent
syst
ems
•(D
EW
ATS)
(e.
g. s
econ
dary
tre
atm
ent
+ re
ed b
ed
syst
ems)
Upfl
ow A
nae
robi
c Sl
udg
e B
lan
ket
•
(UA
SB)
and
oth
er a
nae
robi
c sy
stem
sW
aste
wat
er S
tora
ge a
nd
Trea
tmen
t R
eser
voir
s •
Ch
emic
ally
en
han
ced
prim
ary
trea
tmen
t• L
arge
cit
y ce
ntr
aliz
ed s
yste
m:
Con
ven
tion
al t
reat
men
t +
poli
shin
g po
nds
•SA
T s
yste
ms
•
Hou
seh
olds
wit
h g
arde
n:
On
-sit
e la
trin
es a
nd
alte
rnat
ives
•Se
ptic
tan
ks• C
omm
un
al p
lots
:O
n-
or o
ff-f
arm
tre
atm
ent
via
(ser
ies
of)
•du
g-ou
t po
nds
Sedi
men
tati
on t
raps
for
hel
min
th e
ggs
•T
hre
e-ta
nk
syst
ems
•Sa
nd
filt
er s
yste
ms
• Lar
ge p
lots
or
med
ium
-siz
e ci
ty:
Was
te s
tabi
liza
tion
pon
d sy
stem
s•
2
UA
SB a
nd
oth
er a
nae
robi
c sy
stem
s (a
ble
•to
pro
duce
bio
gas
reve
nu
e)
Lar
ger
peri
-urb
an p
lots
wit
h c
ity-
wid
e se
wer
age
syst
em:
Was
tew
ater
Sto
rage
an
d Tr
eatm
ent
•R
eser
voir
s 2
Sour
ce: A
dapt
ed a
nd m
odifi
ed fr
om W
ord
Ban
k (2
010)
1 T
he e
xam
ples
do
not i
mpl
y a
nece
ssar
y pr
ogre
ssio
n w
ith
incr
easi
ng
econ
omic
dev
elop
men
t. I
n h
igh-
inco
me
cou
ntri
es w
aste
sta
bili
zati
on p
ond
syst
ems,
for
exam
ple,
can
be
the
mos
t app
ropr
iate
an
d ec
onom
ical
ly p
refe
rred
opt
ion
for
trea
tmen
t as
wel
l. T
he t
arge
t sho
uld
be
in a
ny s
itu
atio
n to
fin
d lo
call
y ap
prop
riat
e an
d if
pos
sibl
e re
use
-ori
ente
d sy
stem
s w
here
tre
atm
ent l
evel
s ar
e ba
sed
on r
ecei
vin
g w
ater
bod
ies’
abso
rpti
on c
apac
ity
and
the
tech
nolo
gy o
n lo
call
y vi
able
opt
ion
s (L
ibh
aber
, 20
07; M
urr
ay a
nd
Buck
ley,
201
0).
2 M
ost s
uit
able
whe
re c
onti
nuou
s el
ectr
icit
y su
pply
is a
ch
alle
nge
, but
als
o be
yon
d th
is s
tage
.
OMS-WSHH-Guidance-note1-20100719.indd 9 30/07/10 14:49:43
# 10 # 11
Fig
ur
E 2
: Mu
ltip
le B
arri
er D
ecis
ion
Su
ppor
t F
low
Dia
gram
s
The
se s
impl
ified
flow
-ch
art s
how
s di
ffer
ence
s an
d co
mm
onal
itie
s fo
r de
cisi
on-m
aker
s fa
cing
wat
er q
ual
ity
cond
itio
ns
typi
cal f
or th
e th
ree
stag
es o
f eco
nom
ic d
evel
opm
ent a
long
the
san
itat
ion
ladd
er. T
hey
assu
me
that
ove
rall
heal
th-b
ased
tar
gets
hav
e be
en id
enti
fied
and
/or
that
for
each
bar
rier
ope
rati
onal
qu
alit
y st
anda
rds
hav
e be
en s
et.
a. F
arm
er s
afet
y
Is t
here
an
alte
rnat
ive
sou
rce
wit
h sa
fer
wat
er
that
cou
ld b
e u
sed?
Farm
er is
saf
e fr
om
irri
gati
on w
ater
but
shou
ld m
aint
ain
good
pers
onal
hyg
iene
Rai
se a
war
enes
s am
ong
farm
ers
abou
t ris
ks
that
the
irri
gati
on w
ater
pos
es to
the
m a
nd t
heir
fam
ilie
s.
Dep
endi
ng o
n de
gree
of w
ater
con
tam
inat
ion
impl
emen
t
opti
ons
for:
- P
reve
ntat
ive
heal
th p
rote
ctio
n (i
rrig
atio
n w
ith
less
farm
er-w
ater
con
tact
) an
d se
lf-pr
otec
tion
(clo
thin
g),
- Po
st-e
xpos
ure
was
hin
g an
d re
gula
r de
-wor
min
g.
If p
rodu
ced
crop
s ar
e
eate
n w
itho
ut c
ooki
ng
go to
dia
gram
2b.
Hig
hly-
tre
ated
was
tew
ater
Part
iall
y-tr
eate
d w
aste
wat
er
Unt
reat
ed w
aste
wat
er
Doe
s th
e w
ater
qu
alit
y
mee
t saf
ety
stan
dard
s
for
farm
ers’
expo
sure
?
Yes
No
Yes
No
Yes
OMS-WSHH-Guidance-note1-20100719.indd 10 30/07/10 14:49:43
# 10 # 11
Doe
s th
e w
ater
mee
t
irri
gati
on s
afet
y
stan
dard
s fo
r th
e
give
n ty
pe o
f cro
p?
b. C
onsu
mer
sa
fety
Hig
hly-
tre
ated
was
tew
ater
Part
iall
y-tr
eate
d w
aste
wat
er
Unt
reat
ed w
aste
wat
er
Is t
here
an
alte
rnat
ive
sou
rce
wit
h sa
fer
wat
er
that
cou
ld b
e u
sed?
Yes
Cou
ld o
ther
cro
ps o
f
low
er r
isk
be g
row
n?
No
Rai
se a
war
enes
s am
ong
farm
ers
on r
isk
s fo
r co
nsu
mer
s an
d ow
n b
usi
nes
s
impl
icat
ion
s. D
epen
din
g on
deg
ree
of w
ater
con
tam
inat
ion
im
plem
ent
opti
ons
for:
- Sa
fer
wat
er fe
tch
ing
and
irri
gati
on p
ract
ices
wh
ich
red
uce
cro
p-
wat
er
con
tact
,
- T
he
supp
ort
of n
atu
ral p
ath
ogen
die
-off
,
- Si
mpl
e pr
e- o
r on
-far
m w
ater
tre
atm
ent
(pon
ds,
filt
rati
on)
if fe
asib
le.
Yes
No
Yes
Is t
he p
rodu
ce s
afe
for
con
sum
ptio
n
acco
rdin
g to
giv
en
qual
ity
stan
dard
s?
Is t
here
a r
isk
of
post
-har
vest
cro
p
cont
amin
atio
n?
Yes
Rai
se a
war
enes
s am
ong
vege
tabl
e
sell
ers
and
food
cat
erer
s an
d
supp
ort
mea
sure
s to
red
uce
con
sum
ptio
n r
isk
s vi
a be
tter
mar
ket
han
dli
ng
prac
tice
s, fo
od
hyg
ien
e an
d ef
fect
ive
vege
tabl
e
was
hin
g.
No
Yes
S A F E P r O D u C E
No
No
OMS-WSHH-Guidance-note1-20100719.indd 11 30/07/10 14:49:43
FurTHEr rEADiNg
Bos, R., Carr, R. and B. Keraita (2010). Assessing and mitigating wastewater-related health risk in developing countries: An introduction. In: Drechsel, P.,
C.A. Scott, L. Raschid-Sally, M. Redwood and A. Bahri (eds.) Wastewater irrigation and health: Assessing and mitigation risks in low-income countries.
Earthscan-IDRC-IWMI, UK p. 29-47 www.idrc.ca/openebooks/475-8/
Keraita, B., Drechsel, P., F. Konradsen (2010). Up and down the sanitation ladder: Harmonizing the treatment and multiple-barrier perspectives on risk
reduction in wastewater irrigated agriculture. Irrigation and Drainage Systems (Special Issue on Wastewater reuse) 24 (1-2) 23-35
Libhaber, M. (2007) Appropriate Technology for Wastewater Treatment and Reuse in Developing Countries. In: Huber, H., P. Wilderer and S. Paris (eds)
Water Supply and Sanitation for All. IWA and Huber AG, Germany, ISBN 9781843395140
Murray, A. and C. Buckley (2010). Designing reuse-oriented sanitation infrastructure: The Design for Service Planning Approach. In: Drechsel, P., C.A.
Scott, L. Raschid-Sally, M. Redwood and A. Bahri (eds.) Wastewater irrigation and health: Assessing and mitigation risks in low-income countries.
Earthscan-IDRC-IWMI, UK p. 303-318 www.idrc.ca/openebooks/475-8/
World Bank (2010). Wastewater use in agriculture: An emerging priority. Energy, Transport and Water Department, Water Anchor (ETWWA). The World
Bank (in press).
WHO (2006). Guidelines for the safe use of wastewater, excreta and greywater. Volume 2: Wastewater use in agriculture. World Health Organization,
Geneva, Switzerland.
WHO (2010) Guidelines for drinking-water quality, third edition. Health-based targets (special print of the chapter). www.unwater.org/worldwaterday/
downloads/WHO_IWA/Health-Based_Targets_3_17_10.pdf
ABBrEViATiONS uSED iN THE TABLES
DALY: Disability adjusted Life Years
DEWATS: Decentralized wastewater treatment systems
USEPA: United States Environmental Protection Agency
HACCP: Hazard Analysis and Critical Control Points (approach)
QMRA: Quantitative Microbial Risk Assessment
QCRA: Quantitative Chemical Risk Assessment
SAT: Soil aquifer treatment
UASB: Upflow Anaerobic Sludge Blanket Reactor
This guidance note has been prepared by Pay Drechsel and Bernard Keraita; International Water Management Institute, Ghana and
Colombo. The views expressed in this document are those of the authors alone; they do not necessarily represent the decisions or
stated policy of the World Health Organization, the Food and Agriculture Organization of the United Nations, the International
Development Research Centre or the International Water Management Institute.
OMS-WSHH-Guidance-note1-20100719.indd 12 30/07/10 14:49:43
