sus ainabili y
A icle
The Economic Impac o Clima e Change on U ban D ainage
Mas e Planning in Ba celona
Alejand o O iz 1, Ma ia JoséVelasco 1, Osca Esb i 1, Vicen e Medina 2,* and Beniamino Russo 3,4,5


Ci a ion: O iz, A.; Velasco, M.J.;
Esb i, O.; Medina, V.; Russo, B. The
Economic Impac o Clima e Change
on U ban D ainage Mas e Planning in
Ba celona. Sus ainabili y 2021,13, 71.
h ps://dx.doi.o g/10.3390/su13010071
Recei ed: 7 Oc obe 2020
Accep ed: 18 Decembe 2020
Published: 23 Decembe 2020
Publishe ’s No e: MDPI s ays neu-
al wi h ega d o ju isdic ional claims
in published maps and ins i u ional
a ilia ions.
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censee MDPI, Basel, Swi ze land. This
a icle is an open access a icle dis ibu ed
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license (h ps://c ea i ecommons.o g/
licenses/by/4.0/).
1Ba celona Cicle de l’Aigua (BCASA), Ba celona Ci y Council, Ace 16, 08038 Ba celona, Spain;
[email p o ec ed] (A.O.); [email p o ec ed] (M.J.V.); [email p o ec ed] (O.E.)
2Ba celonaTech, Uni e si a Poli ècnica de Ca alunya (UPC), Jo di Gi ona 1-3, 08034 Ba celona, Spain
3AQUATEC (SUEZ G oup), Paseo de La Zona F anca, 46-48, 08038 Ba celona, Spain;
[email p o ec ed]
4G upo de Ingenie ía Hid áulica y Ambien al (GIHA), Escuela Poli écnica de La Almunia, EUPLA,
Uni e sidad de Za agoza, Calle Mayo , 5, La Almunia de Doña Godina, 50100 Za agoza, Spain
5Flumen Resea ch Ins i u e, Uni e si a Poli ècnica de Ca alunya (UPC), Jo di Gi ona 1-3,
08034 Ba celona, Spain
*Co espondence: [email p o ec ed]
Abs ac :
In he con ex o global change, u ban d ainage in as uc u es mus be planned conside ing
u u e challenges such as new clima e change and u ban g ow h scena ios. La ge ci ies equi e mas e
plans o p ope ly ank and schedule in as uc u e de elopmen . The lood mi iga ion measu es
p oposed in p e ious plans mus be e ised and upda ed o add ess u u e u ban challenges wi h
special ega d o clima e scena ios. Rega ding isk assessmen , he e is no linea ela ionship be ween
an inc ease in ain all and an inc ease in isk alue. Fo isk managemen , he ela ionship be ween
an inc ease in ain all inc ease and he budge o mi iga ion measu es is e en mo e complex. To
in es iga e his ela ionship and he economic impac o he a o emen ioned upda e, a new plan
should be elabo a ed. U ban d ainage mas e plans ha e been de eloped in Ba celona ci y o
he las 50 yea s. In e ms o ain all, he impac o clima e change has been es ablished o be an
inc ease o 7–26% a peak in ensi y, depending on ain all du a ion. The In eg al D ainage Mas e
Plan o Ba celona (PDISBA) add esses hese new challenges. The modi ica ion o ain all scena io
planning and he ypology o mi iga ion measu es esul in an impo an ise in in es men budge ,
in as uc u e li e cycle, and ope a ion and main enance budge s o said in as uc u e. The o al
cos o he planned measu es ou lined in he PDISBA has isen o
€
1.442 million, nea ly double ha
o he p e ious plan de eloped in 2006.
Keywo ds: lood isk managemen ; d ainage planning; cos –bene i analysis
1. In oduc ion
Cu en ly, 54% o he wo ld’s popula ion li es in u ban a eas, a p opo ion ha is
expec ed o inc ease o 66% by 2050 [
1
]. These u ban a eas a e, due o he concen a ion o
popula ion asse s and economic ac i i ies, some o he mos sensi i e egions o na u al
haza ds [
2
]. Indeed, he e is a common ag eemen ega ding he ele ance o he impac o
clima e change on ou socie y [
3
–
5
], wi h u ban looding being a good example [
6
–
8
]. In
his con ex , u ban d ainage sys ems can ail mainly due o a non-s a iona y clima e and
apid u baniza ion and may become less e icien ega ding c ucial issues such as sewe
o e lows and an inc ease in u ban looding [9].
The e o e, u ban lood and en i onmen al isk assessmen s plays a c ucial ole, due
o he need o plan and adop mi iga ion measu es. Speci ically, a comp ehensi e isk
assessmen ( ocused on he managemen o social, economic, and en i onmen al isks) is
he p ope way o quan i a i ely e alua e he bene i s o adap a ion measu es in he ield
o u ban d ainage [
9
–
12
], using i s ools, such as he expec ed annual damage (EAD) [
13
]
o cos –bene i analysis (CBA) [14].
Sus ainabili y 2021,13, 71. h ps://dx.doi.o g/10.3390/su13010071 h ps://www.mdpi.com/jou nal/sus ainabili y
Sus ainabili y 2021,13, 71 2 o 25
Clima e change mus be included in in as uc u e design [
15
,
16
]. In he lood isk
managemen cycle, clima e change modi ies he haza d esul s, al e ing o isk in he inal
alue (in e ms o EAD), and hence, modi ying he mi iga ion measu es as well. The design
c i e ia o such measu es could be he e u n pe iod, he CBA, o he knee/elbow poin ,
bu in all o hem, he e ec o clima e change will appea , he eby modi ying he inal
in es men budge . The complexi y o he comple e p ocess and i s pa icula s eps makes
i di icul o quan i a i ely ela e clima e change o in es men budge .
Big ci ies such as Ba celona ha e been managing u ban looding isk o a leas
50 yea s. This means ha he d ainage ne wo k has been homogeneously adap ed o
he egula ions and he p e e ed design c i e ia; he e o e, a small inc ease in ci cula ing
discha ge could signi ican ly a ec he ne wo k’s global pe o mance. Beyond he damage
cu es, his e ec g ea ly impac s any planned imp o emen s in he ne wo k. To p ope ly
in es iga e hese impac s, he whole isk managemen cycle has been ep oduced o
clima e change scena ios in he ci y o Ba celona. New lood managemen s a egies,
such as hose ela ed o imp o ing he wa e quali y o ecei ing wa e bodies ( om he
Medi e anean Sea and Bèsos Ri e , in his case), include elemen s such as sus ainable
d ainage sys ems (SUDSs) o low-impac de elopmen (LID), no p esen in p e ious plans,
bu which modi y mi iga ion budge s in acco dance wi h he haza d.
I is common o ind p e ious esea ch ha assesses he impac o clima e change
in ela ion o lood isk [
11
,
17
,
18
], bu i is no so common o ind comple e managemen
cycles, including de ailed measu emen s o he impac on big ci ies in e ms o he economy
and u ban planning o o he en i onmen al impac s conside ing he e ec s o combined
sewe o e lows on he ecei ing wa e bodies. Howe e , he e is p e ious esea ch on he
me hodology ega ding how o de elop i [12].
P e ious isk assessmen esea ch on he impac o clima e change e eals ha he
quan i a i e ela ionship be ween isk and p ecipi a ion is no simple [
11
,
13
], due o he
accumula ion o non-linea s eps. This ela ionship is expec ed o be mo e complex o he
mi iga ion budge .
2. PDISBA Mas e Plan
The ci y o Ba celona is loca ed along he wes Medi e anean sho eline and i is
con ined by i e s o he no h and sou h, moun ains o he wes , and sea o he eas . The
mos impo an challenges i will ha e o add ess in ela ion o clima e change (CC) a e
educed wa e a ailabili y, a ising sea le el, inc eased looding and eceding beaches, and
de e io a ion o wa e quali y in he ecei ing wa e bodies. The o ecas ed consequences
o CC will equi e a new pa adigm in u ban planning o his cen u y. A new ime scale
appea s linked o CC, and in as uc u es planned using p esen scena ios will be ou da ed
in he mid- e m. The PDISBA add esses hese challenges by e alua ing he impac o he
nex 80 yea s and p oposing adap a ion measu es o be implemen ed du ing he nex 20
yea s. Howe e , he amoun o he in es men and he complexi y o such p ojec s equi e
de ailed analysis in e ms o echnical de elopmen and economic impac .
In o de o pe o m a long- e m analysis, i is necessa y o include he ope a ion and
managemen ac i i ies and he li e cycle o exis ing and p ojec ed in as uc u es. All o
hese elemen s should be included in he economic e alua ion o he mas e plan. The
selec ed s a egy o execu e he analysis in Ba celona is o pe o m a CBA, which has been
p e iously applied [
19
]. Due o he c oss-in e ac ions be ween measu es, i is no possible
o e alua e hem as independen ac i i ies o o ank hem using he esul s o he CBA.
Mo eo e , i is no possible o co e he whole ange o possible measu e combina ions.
He ein, wo di e en g oups o measu es we e de ined as modeling scena ios and we e
e alua ed. The CBA esul s o he scena ios we e only used o jus i y he in es men s.
Addi ionally, he CBA esul s we e ob ained a he neighbo hood scale and used o he
p io i iza ion o in es men s.
The PDISBA is in ended o se e as an e ec i e u ban esis ance ool ha is capable o
o e ing a se o adap i e s a egies gea ed owa d educing he ulne abili y o he u ban
Sus ainabili y 2021,13, 71 3 o 25
en i onmen and p o ec ing people, asse s, and he en i onmen . The Comp ehensi e
Plan o Ba celona’s Sewe age Sys em (PICBA06), d awn up in 2006, is he plan cu en ly
in o ce. Howe e , i s p ojec ed imespan is no enough o p o ide answe s o he needs
posed by socie y on key issues such as he e ec s o CC and he social e u n on in es men .
Consequen ly, i was el ha he e was a need and jus i ica ion o upda ing he plan, wi h
he aim o esponding o he new social and en i onmen al eali y. Figu e 1shows he
di e en miles ones in he d ainage mas e plan o Ba celona.
Sus ainabili y 2021, 13, x FOR PEER REVIEW 3 o 26
The PDISBA is in ended o se e as an e ec i e u ban esis ance ool ha is capable
o o e ing a se o adap i e s a egies gea ed owa d educing he ulne abili y o he
u ban en i onmen and p o ec ing people, asse s, and he en i onmen . The Comp ehen-
si e Plan o Ba celona’s Sewe age Sys em (PICBA06), d awn up in 2006, is he plan cu -
en ly in o ce. Howe e , i s p ojec ed imespan is no enough o p o ide answe s o he
needs posed by socie y on key issues such as he e ec s o CC and he social e u n on
in es men . Consequen ly, i was el ha he e was a need and jus i ica ion o upda ing
he plan, wi h he aim o esponding o he new social and en i onmen al eali y. Figu e
1 shows he di e en miles ones in he d ainage mas e plan o Ba celona.
Figu e 1. Di e en miles ones in he di e en Ba celona d ainage plans.
Wi h his commi men , he PDISBA is an ambi ious ci y plan capable o deli e ing a
esponse o he u u e challenges ha socie y is calling o , hus becoming he i s sewe -
age and d ainage plan o success ully achie e he ollowing speci ic goals:
• Conside a ion o CC o ecas in i s ain all modeling scena ios;
• Inclusion o a ba hing wa e coas al model;
• Ex ension o he impac analysis o include en i onmen al, social, and economic
damage;
• Inclusion o speci ic measu es o mi iga e CC;
• Conside a ion o sus ainable u ban d ainage sys ems, also known as low-impac de-
elopmen ;
• Inclusion o u ban esilience analysis;
• Inclusion o cos –bene i analysis and economic e iciency;
• Inclusion o long- e m analysis and mid- e m in es men .
3. De ini ion o Hyd ological Scena ios
Clima e change mi iga ion is one o he main goals o he PDISBA. The selec ed
me hod o include CC in he plan is h ough ex eme ain all scena ios [20,21]. Ins ead o
di ec ly using addi ional coe icien s o weigh he exis ing ain all scena ios, i was de-
cided o pe o m a comple e eanalysis o he a ailable ain all da a.
The en i onmen al impac o he u ban d ainage in Ba celona is mainly p o oked by
he combined sewe o e lows (CSOs) in he sea and in he i e s. In o de o p ope ly
analyze he e ec o he plan’s measu es on he CSO, a s anda d hyd ological yea was
de ined as ha ing mo e han 50 ain all e en s.
3.1. Rain all Time Se ies Reanalysis and S o m Design
To da e, s udies in o Ba celona’s ain all ha e been calcula ed using ain all da a om
he Fab a Obse a o y ain gauge s a ion. The ime se ies includes almos 100 yea s o
da a, bu he loca ion o he obse a o y in he moun ains abo e he ci y canno ensu e, a
Figu e 1. Di e en miles ones in he di e en Ba celona d ainage plans.
Wi h his commi men , he PDISBA is an ambi ious ci y plan capable o deli e ing a
esponse o he u u e challenges ha socie y is calling o , hus becoming he i s sewe age
and d ainage plan o success ully achie e he ollowing speci ic goals:
•Conside a ion o CC o ecas in i s ain all modeling scena ios;
•Inclusion o a ba hing wa e coas al model;
•
Ex ension o he impac analysis o include en i onmen al, social, and economic
damage;
•Inclusion o speci ic measu es o mi iga e CC;
•
Conside a ion o sus ainable u ban d ainage sys ems, also known as low-impac
de elopmen ;
•Inclusion o u ban esilience analysis;
•Inclusion o cos –bene i analysis and economic e iciency;
•Inclusion o long- e m analysis and mid- e m in es men .
3. De ini ion o Hyd ological Scena ios
Clima e change mi iga ion is one o he main goals o he PDISBA. The selec ed
me hod o include CC in he plan is h ough ex eme ain all scena ios [
20
,
21
]. Ins ead
o di ec ly using addi ional coe icien s o weigh he exis ing ain all scena ios, i was
decided o pe o m a comple e eanalysis o he a ailable ain all da a.
The en i onmen al impac o he u ban d ainage in Ba celona is mainly p o oked by
he combined sewe o e lows (CSOs) in he sea and in he i e s. In o de o p ope ly
analyze he e ec o he plan’s measu es on he CSO, a s anda d hyd ological yea was
de ined as ha ing mo e han 50 ain all e en s.
3.1. Rain all Time Se ies Reanalysis and S o m Design
To da e, s udies in o Ba celona’s ain all ha e been calcula ed using ain all da a om
he Fab a Obse a o y ain gauge s a ion. The ime se ies includes almos 100 yea s o da a,
bu he loca ion o he obse a o y in he moun ains abo e he ci y canno ensu e, a p io i,
ha i is ep esen a i e o he whole ci y. Mo eo e , he empo al esolu ion o he da a
is less accu a e han he new ain gauges’ ime s ep. Since 1994, he ci y has de eloped a
Sus ainabili y 2021,13, 71 4 o 25
managemen plan o con ol he sewe sys em, ins alling a o al o 25 new ain gauges ha
co e i s en i e su ace. Hence, a long ime se ies o ain all da a is a ailable (app oxima ely
24 yea s eco ded by 25 ain all g aphs achie ed by ipping bucke ain gauges), which
pe mi s he de elopmen o he en i e s a is ical me hodology based on eal da a.
The s a ing hypo hesis is ha he exis ing da a do no ye su e signi ican CC ends.
Subsequen ly, he in luence o he impac o clima e change can be conside ed explici ly
a e he ain all analysis, in acco dance wi h he u u e scena ios ob ained in ecen s udies
o he Ba celona Ci y Council and a ious clima e models.
I is possible o di ec ly es ima e he empi ical exceedance p obabili y o he ain all
da a eco ded in he ain gauges du ing he yea s conside ed. This me hod is a good
es ima ion o he maximum ain all in ensi y o e u n pe iods sho e han he eco ded
yea s. Fo his case, his me hod was assumed o be alid o e u n pe iods o up o
10 yea s, using 24 yea s o da a. The annual maximum in ensi y cu es o each e u n
pe iod be ween yea s 1 and 10 we e comple ed by in e pola ion o he a ailable da a om
he empi ical in ensi y–du a ion– equency (IDF) able.
Fo e u n pe iods abo e o equal o he numbe o a ailable da a, an ex apola ion
mus be pe o med. The maximum annual in ensi ies o he e u n pe iods o 20, 25, 30,
50, 75, 100, and 500 yea s we e calcula ed by ex apola ing he pa ame e s acco ding o
he Gumbel o ex eme ype I p obabili y dis ibu ion. Wi h he cu es co esponding o
he 95 h pe cen ile o each e u n pe iod, join IDF cu es o he ci y o Ba celona we e
cons uc ed o bo h he empi ical cu es and he cu es ex apola ed by Gumbel.
Figu e 2compa es he IDF cu es ob ained using he Fab a Obse a o y da ase and
he new da ase de eloped in he PDISBA using he new ain gauges’ da a. The plo shows
he 10-yea e u n pe iod plo s.
Sus ainabili y 2021, 13, x FOR PEER REVIEW 4 o 26
p io i, ha i is ep esen a i e o he whole ci y. Mo eo e , he empo al esolu ion o he
da a is less accu a e han he new ain gauges’ ime s ep. Since 1994, he ci y has de eloped
a managemen plan o con ol he sewe sys em, ins alling a o al o 25 new ain gauges
ha co e i s en i e su ace. Hence, a long ime se ies o ain all da a is a ailable (app ox-
ima ely 24 yea s eco ded by 25 ain all g aphs achie ed by ipping bucke ain gauges),
which pe mi s he de elopmen o he en i e s a is ical me hodology based on eal da a.
The s a ing hypo hesis is ha he exis ing da a do no ye su e signi ican CC
ends. Subsequen ly, he in luence o he impac o clima e change can be conside ed ex-
plici ly a e he ain all analysis, in acco dance wi h he u u e scena ios ob ained in e-
cen s udies o he Ba celona Ci y Council and a ious clima e models.
I is possible o di ec ly es ima e he empi ical exceedance p obabili y o he ain all
da a eco ded in he ain gauges du ing he yea s conside ed. This me hod is a good es i-
ma ion o he maximum ain all in ensi y o e u n pe iods sho e han he eco ded
yea s. Fo his case, his me hod was assumed o be alid o e u n pe iods o up o 10
yea s, using 24 yea s o da a. The annual maximum in ensi y cu es o each e u n pe iod
be ween yea s 1 and 10 we e comple ed by in e pola ion o he a ailable da a om he
empi ical in ensi y–du a ion– equency (IDF) able.
Fo e u n pe iods abo e o equal o he numbe o a ailable da a, an ex apola ion
mus be pe o med. The maximum annual in ensi ies o he e u n pe iods o 20, 25, 30,
50, 75, 100, and 500 yea s we e calcula ed by ex apola ing he pa ame e s acco ding o
he Gumbel o ex eme ype I p obabili y dis ibu ion. Wi h he cu es co esponding o
he 95 h pe cen ile o each e u n pe iod, join IDF cu es o he ci y o Ba celona we e
cons uc ed o bo h he empi ical cu es and he cu es ex apola ed by Gumbel.
Figu e 2 compa es he IDF cu es ob ained using he Fab a Obse a o y da ase and
he new da ase de eloped in he PDISBA using he new ain gauges’ da a. The plo shows
he 10-yea e u n pe iod plo s.
Figu e 2. Compa ison be ween he In ensi y–Du a ion–F equency (IDF) cu es used in he p e ious mas e plans and he
new plan, PDISBA (“Fab a_*”). The maximum and minimum lines we e ob ained using he di e en ain gauges ac oss
he ci y. The selec ed in ensi y (“In ensi y_BCN_2018”) co esponds o he 95% con idence in e al.
Figu e 2.
Compa ison be ween he In ensi y–Du a ion–F equency (IDF) cu es used in he p e ious mas e plans and he
new plan, PDISBA (“Fab a_*”). The maximum and minimum lines we e ob ained using he di e en ain gauges ac oss he
ci y. The selec ed in ensi y (“In ensi y_BCN_2018”) co esponds o he 95% con idence in e al.
As has been s a ed, he selec ed in ensi y o he IDF cu es co esponds o he 95%
con idence in e al o he da a. The blue line in he plo shows he maximum obse ed
in ensi y and he cyan line co esponds o he minimum. The dispe sion co esponds o he
Sus ainabili y 2021,13, 71 5 o 25
25 a ailable ain gauges. I can be obse ed ha , o sho du a ions, he Fab a Obse a o y
IDF cu es o e es ima ed he ain all in ensi y, bu o long du a ions, hey unde es ima ed
he p ecipi a ion.
Figu e 3shows he IDF cu es ob ained by he empi ical me hod o e u n pe iods
equal o o less han 10 yea s, as well as he IDF cu es ob ained by ex apola ion using
he Gumbel dis ibu ion. The o me exhibi s a smoo he shape, due o he ma hema ical
ex apola ion.
Sus ainabili y 2021, 13, x FOR PEER REVIEW 5 o 26
As has been s a ed, he selec ed in ensi y o he IDF cu es co esponds o he 95%
con idence in e al o he da a. The blue line in he plo shows he maximum obse ed
in ensi y and he cyan line co esponds o he minimum. The dispe sion co esponds o
he 25 a ailable ain gauges. I can be obse ed ha , o sho du a ions, he Fab a Obse -
a o y IDF cu es o e es ima ed he ain all in ensi y, bu o long du a ions, hey unde -
es ima ed he p ecipi a ion.
Figu e 3 shows he IDF cu es ob ained by he empi ical me hod o e u n pe iods
equal o o less han 10 yea s, as well as he IDF cu es ob ained by ex apola ion using
he Gumbel dis ibu ion. The o me exhibi s a smoo he shape, due o he ma hema ical
ex apola ion.
Figu e 3. IDF cu es ob ained using he da a om he 1994–2018 pe iod and i ed o he 95% con idence in e al o he
empi ical IDF cu es.
Hye og aphs, designed using syn he ic ain all scena ios, we e cons uc ed using he
al e na ing block me hod [22] and he S-cu es me hod [23]. Analysis o he empo al pa -
e n o he ain all was conduc ed on a selec ion o he ex eme ain all e en s eco ded in
he las 24 yea s. Acco ding o he s udy o he empo al dis ibu ion o he ain, he a e -
age du a ion a ied be ween 160 and 230 min o he di e en cu es. In he al e na ing
blocks hye og aphs, he ails co esponding o he di e ence be ween 160 and 230 min
we e analyzed and inally disca ded; he e o e, a ain all du a ion o 160 min was inally
selec ed. The p ecipi a ion du a ion o he p e ious plans was app oxima ely 60 min [24].
The second pa ame e o be es ablished was he in ensi y peak posi ion in he hye o-
g aph, o which he al e na ing block me hod pe mi ed o ansla e he cen al in ensi y
peak in o de o ad ance o delay i . The analysis was pe o med using he S-cu es S1,
S2, and S3 i ed o he ain gauge da a. I was obse ed ha o sho e e u n pe iods,
he ain showed a cen e ed peak. Fo ains co esponding o e u n pe iods g ea e han
T = 10 yea s, he e was a simila p obabili y o inding he h ee ypes o cu e (S1, S2, and
S3). To conclude which was he mos ha m ul, se e al model uns we e pe o med using
h ee p o o ypes o ain all empo al dis ibu ion. Fo he 10-yea e u n pe iod, i was
obse ed ha a delayed peak esul ed in highe discha ge.
Figu e 3.
IDF cu es ob ained using he da a om he 1994–2018 pe iod and i ed o he 95% con idence in e al o he
empi ical IDF cu es.
Hye og aphs, designed using syn he ic ain all scena ios, we e cons uc ed using he
al e na ing block me hod [
22
] and he S-cu es me hod [
23
]. Analysis o he empo al
pa e n o he ain all was conduc ed on a selec ion o he ex eme ain all e en s eco ded
in he las 24 yea s. Acco ding o he s udy o he empo al dis ibu ion o he ain, he
a e age du a ion a ied be ween 160 and 230 min o he di e en cu es. In he al e na ing
blocks hye og aphs, he ails co esponding o he di e ence be ween 160 and 230 min
we e analyzed and inally disca ded; he e o e, a ain all du a ion o 160 min was inally
selec ed. The p ecipi a ion du a ion o he p e ious plans was app oxima ely 60 min [
24
].
The second pa ame e o be es ablished was he in ensi y peak posi ion in he hye o-
g aph, o which he al e na ing block me hod pe mi ed o ansla e he cen al in ensi y
peak in o de o ad ance o delay i . The analysis was pe o med using he S-cu es S1, S2,
and S3 i ed o he ain gauge da a. I was obse ed ha o sho e e u n pe iods, he
ain showed a cen e ed peak. Fo ains co esponding o e u n pe iods g ea e han T = 10
yea s, he e was a simila p obabili y o inding he h ee ypes o cu e (S1, S2, and S3). To
conclude which was he mos ha m ul, se e al model uns we e pe o med using h ee
p o o ypes o ain all empo al dis ibu ion. Fo he 10-yea e u n pe iod, i was obse ed
ha a delayed peak esul ed in highe discha ge.
Figu e 4shows he inal hye og aph o he selec ed 10-yea e u n pe iod unde he
ac ual condi ions. The e ec o CC was applied o hese alues, and he peak in ensi y was
177.2 mm/h.

Sus ainabili y 2021,13, 71 6 o 25
Sus ainabili y 2021, 13, x FOR PEER REVIEW 6 o 26
Figu e 4 shows he inal hye og aph o he selec ed 10-yea e u n pe iod unde he
ac ual condi ions. The e ec o CC was applied o hese alues, and he peak in ensi y was
177.2 mm/h.
Figu e 4. Design s o m o Ba celona co esponding o a 10-yea e u n pe iod.
3.2. S anda d Yea o CSO E alua ion
As men ioned in he in oduc ion, a con inuous modeling o a one-yea du a ion o
ain all is equi ed o e alua e he educ ion o CSOs a e he implemen a ion o adap a-
ion measu es. The ypical indica o o e alua e he pe o mance o CSO measu es is using
he numbe o e en s pe yea [25]. All o he a ailable ime se ies we e analyzed in e ms
o o al p ecipi a ion, numbe o e en s, and dis ance be ween e en s. The yea 2009 was
selec ed as he mos ep esen a i e o he se ies. The o al ain all was 520 mm and he
numbe o e en s was 60. Figu e 5 shows he da a. The plo only includes non-ze o alues;
hence, he ho izon al axis is no a con inuous ime line.
Figu e 5. Time se ies used o e alua e he impac o combined sewe o e lows (CSO), wi h a o al
du a ion o one yea .
Figu e 4. Design s o m o Ba celona co esponding o a 10-yea e u n pe iod.
3.2. S anda d Yea o CSO E alua ion
As men ioned in he in oduc ion, a con inuous modeling o a one-yea du a ion o
ain all is equi ed o e alua e he educ ion o CSOs a e he implemen a ion o adap a ion
measu es. The ypical indica o o e alua e he pe o mance o CSO measu es is using he
numbe o e en s pe yea [
25
]. All o he a ailable ime se ies we e analyzed in e ms
o o al p ecipi a ion, numbe o e en s, and dis ance be ween e en s. The yea 2009 was
selec ed as he mos ep esen a i e o he se ies. The o al ain all was 520 mm and he
numbe o e en s was 60. Figu e 5shows he da a. The plo only includes non-ze o alues;
hence, he ho izon al axis is no a con inuous ime line.
Sus ainabili y 2021, 13, x FOR PEER REVIEW 6 o 26
Figu e 4 shows he inal hye og aph o he selec ed 10-yea e u n pe iod unde he
ac ual condi ions. The e ec o CC was applied o hese alues, and he peak in ensi y was
177.2 mm/h.
Figu e 4. Design s o m o Ba celona co esponding o a 10-yea e u n pe iod.
3.2. S anda d Yea o CSO E alua ion
As men ioned in he in oduc ion, a con inuous modeling o a one-yea du a ion o
ain all is equi ed o e alua e he educ ion o CSOs a e he implemen a ion o adap a-
ion measu es. The ypical indica o o e alua e he pe o mance o CSO measu es is using
he numbe o e en s pe yea [25]. All o he a ailable ime se ies we e analyzed in e ms
o o al p ecipi a ion, numbe o e en s, and dis ance be ween e en s. The yea 2009 was
selec ed as he mos ep esen a i e o he se ies. The o al ain all was 520 mm and he
numbe o e en s was 60. Figu e 5 shows he da a. The plo only includes non-ze o alues;
hence, he ho izon al axis is no a con inuous ime line.
Figu e 5. Time se ies used o e alua e he impac o combined sewe o e lows (CSO), wi h a o al
du a ion o one yea .
Figu e 5.
Time se ies used o e alua e he impac o combined sewe o e lows (CSO), wi h a o al
du a ion o one yea .
Sus ainabili y 2021,13, 71 7 o 25
3.3. E ec s o Clima e Change on Ex eme and Mode a e Rain all E en s in Ba celona
The e ec s o clima e change on he u ban hyd ological cycle due o a po en ial
inc ease in ex eme ain all episodes should be conside ed in o de o p e en u u e
p oblems in u ban d ainage sys ems. IDF cu es a e commonly used o design di e en
ypes o hyd aulic s uc u es in he ield o u ban d ainage. IDF cu es could be al e ed
due o a p esumed inc ease in ex eme in ense ain all caused by clima e change. A gene al
o e iew abou his issue was p esen ed by Willems e al. [7].
Con a y o wha happens in he high-o mid-la i ude egions o he wo ld, in which
an inc ease in o al p ecipi a ion has been epo ed [
26
], se e al s udies ha e shown a
dec easing dominan end du ing he las decades in he Medi e anean a ea. Indeed, he
egional clima e change assessmen epo p epa ed by esea che s om he CLIVAR-Spain
ne wo k [
27
] concluded ha he annual ain all in he Ibe ian Peninsula in he las h ee
decades has dec eased signi ican ly compa ed o he 1960s and 1970s. Despi e his dec ease
in o al p ecipi a ion, an inc ease in ex eme p ecipi a ion has been obse ed. Simula ions
o he 21s cen u y ypically use clima e models o p edic signi ican dec eases in o al
p ecipi a ion in he Medi e anean a ea [
28
], al hough some p ojec ions o egional models
ha e shown a possible inc ease in o en ial ain all [
28
,
29
], wi h sho e and mo e in ense
p ecipi a ion episodes.
Acco ding o he V epo on clima e change o he In e go e nmen al Panel on
Clima e Change (IPCC), known as AR5 in English, in some a eas o he wo ld, he equency,
in ensi y, and/o amoun o s ong p ecipi a ion will inc ease, bu , due o high unce ain y,
local de ailed s udies a e equi ed [28,30].
The assessmen o he po en ial in luence o clima e change on he in ensi y o ex eme
ain all is e y in e es ing in he Medi e anean a ea, especially in densely popula ed u ban
a eas wi h complex sewe sys ems, ulne able in as uc u es, and u ban se ices in he
case o ex eme ain all episodes.
In Ba celona, he i s e alua ion o he possible in luence o clima e change on ex eme
p ecipi a ion was ca ied ou by Rod íguez e al. [
21
]. The au ho s analyzed u u e se ies
o daily p ecipi a ion o he pe iod o 2000–2099, ob ained h ough i e gene al ci cula ion
models unde ou u u e special epo s on emissions scena ios (SRES) clima e scena ios o
g eenhouse gas emissions (A1B, A2, B1, and B2) and applying he s a is ical downscaling
me hod o six ain all s a ions loca ed in he me opoli an a ea o Ba celona.
F om hese se ies, he u u e changes o be expec ed in he IDF cu es o Ba celona,
o each clima ic scena io conside ed, we e calcula ed. To achie e his, wo di e en ime
educ ion (o downscaling) me hods we e used. In he i s , i was assumed ha he ela i e
a ia ions o p ecipi a ion be ween he p esen and he u u e a e he same o any du a ion
less han 24 h. Meanwhile, o he second, which was based on he scale p ope ies o
p ecipi a ion, he es ima es o hese a ia ions depend on he du a ion.
In pa icula , in his s udy, he clima e change ac o s c
we e de ined by hou ly
in ensi y o di e en empo al ho izons, such as he a io be ween he ain all in ensi y
wi h a e u n pe iod Tand o a ce ain du a ion and he co esponding ain all in ensi y
o he u u e wi h he same Tand [31,32]:
c =I( ,T) u u
I( ,T)p esen
(1)
These ypes o alues can be applied di ec ly o he in ensi ies o he design p ojec
s o m, ob aining a new ain all hye og aph o u u e scena ios.
The empo al downscaling echnique, based on he ac al p ope ies o ain, was
applied up o a du a ion o 1 h, al hough clima ic change ac o s we e applied o he 5 min
in ensi ies as a be e app oxima ion a ailable on he da e o he s udy. Fo he pe iod o
2066–2099, unde scena ios A1B, A2, B1, and B2, he clima e change ac o s a ied om
1.02 o 1.20 o e u n pe iods be ween 1 and 500 yea s, hose o scena io B2 gene ally
being he g ea es [21].
Sus ainabili y 2021,13, 71 8 o 25
Rep esen a i e concen a ion pa hway (RCP) scena ios a e he new se o scena ios
de eloped by he IPCC o he Fi h Assessmen Repo (AR5) [
26
,
33
]. The pa hways
desc ibe ou possible clima e u u es based on adia i e o cing SRES.
Recen ly, in he con ex o he H2020 RESCCUE p ojec (Resilience o Cope wi h
Clima e Change in U ban A eas–A Mul i-Sec o ial App oach Focusing on Wa e ) (www.
esccue.es), new clima ic p ojec ions conce ning se e al clima e a iables ( empe a u e,
p ecipi a ion, sea le el ise, hea wa e, d ough , e c.) we e de eloped o se e al Eu opean
ci ies (Ba celona, B is ol, and Lisbon) [34].
Fo he case o Ba celona and he p ecipi a ion a iable, he his o ical se ies o 20
ipping bucke plu iome e s o he BCASA ain gauge ne wo k wi h a esolu ion o 5 min
we e used, such as he da a om he ERA-In e im eanalysis and he o 10 clima ic CMIP5
models p oposed by he V epo o he ICPP [
34
]. The p ojec ions conce ning 20 ain all
ime se ies co esponding o he ain all gauge s a ions in Ba celona we e achie ed h ough
a s a is ical wo-s ep analogue/ eg ession downscaling me hod success ully implemen ed
in o he ecen s udies in Spain [
35
,
36
]. The gene al a mosphe ic ci cula ion models we e
o ced by RCPs 4.5 and 8.5, and p e iously, hey we e alida ed o he his o ical con ol
pe iod o 1976–2005.
The analysis o ex eme ain all episodes on he plu iome ic ain all se ies ( o he pe-
iod o 2071–2100) o he mos ep esen a i e plu iome e o he BCASA ain gauge ne wo k
( he Facul y o Physics S a ion) allowed o achie e new maximum ain all in ensi ies and
new alues o clima e change coe icien s in he ange be ween 1.07 and 1.26, depending
on he equency and du a ion o each maximum ain all in ensi y (
Table 1
) [
37
,
38
]. These
alues ep esen he 50 h pe cen ile o he esul s ob ained by an ensemble s a egy consid-
e ing all o he ou pu s p o ided by he 10 gene al a mosphe ic ci cula ion models o ced by
RCPs 4.5 and 8.5 in o de o ake in o accoun he unce ain y ela ed o model/ un selec ion
and he RCP scena io conside ed. The new ange o clima e change coe icien s achie ed
in his s udy is qui e simila o he ange achie ed by
Rod iguez e al. [21]
, con i ming he
same end o he p ojec ions abou ex eme ain all e en s in Ba celona, no wi hs anding
he use o di e en gene al a mosphe ic ci cula ion models and di e en clima e change
scena ios (SRES and RCPs) ela ed o he IV and V epo s o ICCP.
Table 1.
Clima e change ac o s o he ime pe iod 2071–2100, including di e en e u n pe iod sand
du a ions up o 60 min o he ci y o Ba celona (Facul a d’Es acióde Física).
Re u n
Pe iod
Du a ion
5 10 15 20 25 30 35 40 45 50 55 60
1 yea
1.16
1.18 1.17
1.14
1.13 1.11
1.10
1.09 1.09 1.10 1.10 1.11
2 yea s
1.15
1.18 1.17
1.14
1.13 1.11
1.10
1.09 1.09 1.10 1.10 1.11
5 yea s
1.13
1.17 1.16
1.15
1.12 1.09
1.10
1.10 1.12 1.11 1.11 1.10
10 yea s
1.11
1.19 1.19
1.17
1.14 1.10
1.11
1.11 1.12 1.11 1.11 1.12
25 yea s
1.09
1.18 1.21
1.19
1.16 1.12
1.12
1.11 1.13 1.11 1.11 1.13
50 yea s
1.08
1.18 1.22
1.2
1.16 1.12
1.13
1.11 1.13 1.11 1.11 1.13
100 yea s
1.07
1.18 1.24
1.21
1.17 1.13
1.14
1.12 1.13 1.12 1.12 1.14
500 yea s
1.07
1.17 1.26
1.22
1.18 1.14
1.15
1.13 1.14 1.13 1.13 1.15
The clima ic change coe icien s ob ained o he u u e ime pe iod o 2071–2100 and
he e u n pe iods o T1, T10, T50, T100, and T500 we e applied di ec ly o he p ojec s o ms
p oposed in he PDISBA, in o de o ake in o accoun he e ec s o clima e change on he
IDF cu es, and consequen ly, on he d ainage capaci y o he ci y and he socioeconomic
impac s po en ially gene a ed om o he se ices.
The RESCCUE p ojec also p o ided his o ical and u u e ain all ime se ies o be
used as inpu in he u ban d ainage and sea wa e quali y models. Ten di e en clima e
Sus ainabili y 2021,13, 71 9 o 25
models we e used o p o ide 5 min downscaled ain all ime se ies in Ba celona, based
on his o ical (1976–2005) and u u e (2071–2100) pe iod simula ions o ced by bo h RCPs
8.5 and 4.5. The achie ed esul s show ha he simula ed annual ain all olume o he
his o ical 1997–2005 pe iod and he numbe o annual ain all e en s we e simila o he
obse ed mean alues, while he u u e simula ed annual ain all olumes and annual
numbe o e en s sligh ly dec eased compa ed o he his o ical simula ion pe iod.
Wi h hese analyses, i can be concluded ha he u u e ain all scena ios ele an o
he analysis o he impac s o CSOs on he sea wa e quali y o Ba celona a e unlikely o
ge wo se. The e o e, u u e con inuous ain all ime se ies wi h en i onmen al design
pu poses we e conside ed o be he same as he his o ical ain alls [
38
]. The a ailable
clima e change ac o s we e o du a ions o 5–60 min. In o de o be able o apply his
ans o ma ion o du a ions abo e 60 min, he end was p opaga ed o each o he e u n
pe iods.
While he a ailable clima e change ac o s did no co espond exac ly o he pe iod
calcula ed by he IDF (1994–2018), hey we e used as a e e ence o ob ain he o ecas o
he IDF cu es, including he in luence o clima e change. The u u e ain all o he e u n
pe iods o T1, T5, T10, T25, T100, and T500 was also calcula ed.
Figu e 6shows a compa ison be ween he design ain all o a 10-yea e u n pe iod
calcula ed wi h ain all da a up o 2018 and he o ecas o he pe iod 2071–2100 acco ding
o he clima e change coe icien s. The blue is he cu en ain, while ed indica es he
u u e inc ease in ain all.
Sus ainabili y 2021, 13, x FOR PEER REVIEW 9 o 26
on his o ical (1976–2005) and u u e (2071–2100) pe iod simula ions o ced by bo h RCPs
8.5 and 4.5. The achie ed esul s show ha he simula ed annual ain all olume o he
his o ical 1997–2005 pe iod and he numbe o annual ain all e en s we e simila o he
obse ed mean alues, while he u u e simula ed annual ain all olumes and annual
numbe o e en s sligh ly dec eased compa ed o he his o ical simula ion pe iod.
Wi h hese analyses, i can be concluded ha he u u e ain all scena ios ele an o
he analysis o he impac s o CSOs on he sea wa e quali y o Ba celona a e unlikely o
ge wo se. The e o e, u u e con inuous ain all ime se ies wi h en i onmen al design
pu poses we e conside ed o be he same as he his o ical ain alls [38]. The a ailable cli-
ma e change ac o s we e o du a ions o 5–60 min. In o de o be able o apply his ans-
o ma ion o du a ions abo e 60 min, he end was p opaga ed o each o he e u n
pe iods.
While he a ailable clima e change ac o s did no co espond exac ly o he pe iod
calcula ed by he IDF (1994–2018), hey we e used as a e e ence o ob ain he o ecas o
he IDF cu es, including he in luence o clima e change. The u u e ain all o he e u n
pe iods o T1, T5, T10, T25, T100, and T500 was also calcula ed.
Figu e 6 shows a compa ison be ween he design ain all o a 10-yea e u n pe iod
calcula ed wi h ain all da a up o 2018 and he o ecas o he pe iod 2071–2100 acco d-
ing o he clima e change coe icien s. The blue is he cu en ain, while ed indica es he
u u e inc ease in ain all.
Figu e 6. Compa ison o cu en and u u e design ain all conside ing clima e change o T = 10
yea s.
4. Hyd aulic Model Cons uc ion
A model is a ma hema ical ep esen a ion o phenomena o p ocesses ha occu in
eali y in o de o analyze hem, o desc ibe and explain hei cu en beha io , and hus
o p edic hei u u e beha io unde o he condi ions. In he case o sewe sys ems, he
s uc u e o he model is buil a ound h ee basic sys ems: he pipeline ne wo k, he ea -
men plan s, and he ecei ing en i onmen . These h ee sys ems a e comple ely in e e-
la ed, so hey need o be s udied and managed oge he .
Figu e 6.
Compa ison o cu en and u u e design ain all conside ing clima e change o
T = 10 yea s.
4. Hyd aulic Model Cons uc ion
A model is a ma hema ical ep esen a ion o phenomena o p ocesses ha occu in
eali y in o de o analyze hem, o desc ibe and explain hei cu en beha io , and hus
o p edic hei u u e beha io unde o he condi ions. In he case o sewe sys ems,
he s uc u e o he model is buil a ound h ee basic sys ems: he pipeline ne wo k, he
ea men plan s, and he ecei ing en i onmen . These h ee sys ems a e comple ely
in e ela ed, so hey need o be s udied and managed oge he .
Sus ainabili y 2021,13, 71 16 o 25
he e ec s o he ne wo k’s aging is di ec ly linked o he loss o quali y o al e na i e wa e
esou ces due o he pollu ion o he unde g ound aqui e . The Ba celona Ci y Council
cu en ly sa is ies municipal wa e needs ha do no equi e d inking quali y by u ilizing
g oundwa e . Op imum ne wo k main enance he e o e di ec ly impac s he ese es o
al e na i e wa e esou ces.
Sus ainabili y 2021, 13, x FOR PEER REVIEW 16 o 26
Figu e 11. S uc u al measu es planned o mi iga ion in he In eg al D ainage Mas e Plan o Ba celona (PDISBA).
5.3.3. Main enance as a Basic Value o Sus ainabili y
All o hese new in es men s equi e a sus ainable conse a ion plan o he sewe -
age and d ainage asse s ha conside s he e ec s o aging and he pace o eplacemen .
One o he e ec s o he ne wo k’s aging is di ec ly linked o he loss o quali y o al e na-
i e wa e esou ces due o he pollu ion o he unde g ound aqui e . The Ba celona Ci y
Council cu en ly sa is ies municipal wa e needs ha do no equi e d inking quali y by
u ilizing g oundwa e . Op imum ne wo k main enance he e o e di ec ly impac s he e-
se es o al e na i e wa e esou ces.
A p esen , he Ci y Council epai s he sewe sys em a an a e age a e o 7.2
km/yea , which means a eno a ion a e o 0.47%. Ne wo k main enance e o s he e o e
need o be doubled o each op imum main enance le els om he poin o iew o asse
sus ainabili y and p ese ing al e na i e wa e esou ces.
The Conse a ion and Main enance sec ion in he PDISBA s a es ha op imum, sus-
ainable main enance means mo ing owa d a eno a ion a e o 1%, i.e., epai ing 16 km
a yea . This inc eased epai a e would la en he aging cu e and ensu e an op imum
se ice le el a minimum cos , hus helping o main ain and p ese e he quali y o
g oundwa e ese es.
Figu e 12 shows he cu en le el o damage o Ba celona’s sewe age sys em, le els
4 and 5 being ully damaged pipes. Ten pe cen o he cu en ne wo k is no able o p o-
ide he equi ed le el o se ice.
Figu e 11. S uc u al measu es planned o mi iga ion in he In eg al D ainage Mas e Plan o Ba celona (PDISBA).
A p esen , he Ci y Council epai s he sewe sys em a an a e age a e o 7.2 km/yea ,
which means a eno a ion a e o 0.47%. Ne wo k main enance e o s he e o e need o be
doubled o each op imum main enance le els om he poin o iew o asse sus ainabili y
and p ese ing al e na i e wa e esou ces.
The Conse a ion and Main enance sec ion in he PDISBA s a es ha op imum, sus-
ainable main enance means mo ing owa d a eno a ion a e o 1%, i.e., epai ing 16
km a yea . This inc eased epai a e would la en he aging cu e and ensu e an op i-
mum se ice le el a minimum cos , hus helping o main ain and p ese e he quali y o
g oundwa e ese es.
Figu e 12 shows he cu en le el o damage o Ba celona’s sewe age sys em, le els 4
and 5 being ully damaged pipes. Ten pe cen o he cu en ne wo k is no able o p o ide
he equi ed le el o se ice.
5.4. Residual Risk Analysis
The p oposed measu es in he plan a e no able o comple ely elimina e he lood isk,
so he emainde o he isk is e alua ed unde di e en condi ions. Using he esidual isk,
i will be possible, in he ollowing, o es ima e he isk managemen bene i .
5.4.1. Ex ao dina y Hyd ological Scena ios o Flood Analysis
Fo he syn he ic ain all e en o a 10-yea e u n pe iod wi h clima e change, i is
e i ied ha he objec i es o p o ec ion o ope a ion o he ne wo k in low condi ions and
o a oid loods ha e no been able o each 100%, al hough he educ ions wi h espec o
diagnoses a e e y impo an . 98% o loods a e a oided and isk is p ac ically comple e
o his e u n pe iod (Table 3).

Sus ainabili y 2021,13, 71 17 o 25
Sus ainabili y 2021, 13, x FOR PEER REVIEW 17 o 26
Figu e 12. Le el o damage in he exis ing ne wo k. PDISBA includes Le el 4 and 5 ixing.
5.4. Residual Risk Analysis
The p oposed measu es in he plan a e no able o comple ely elimina e he lood
isk, so he emainde o he isk is e alua ed unde di e en condi ions. Using he esid-
ual isk, i will be possible, in he ollowing, o es ima e he isk managemen bene i .
5.4.1. Ex ao dina y Hyd ological Scena ios o Flood Analysis
Fo he syn he ic ain all e en o a 10-yea e u n pe iod wi h clima e change, i is
e i ied ha he objec i es o p o ec ion o ope a ion o he ne wo k in low condi ions
and o a oid loods ha e no been able o each 100%, al hough he educ ions wi h espec
o diagnoses a e e y impo an . 98% o loods a e a oided and isk is p ac ically comple e
o his e u n pe iod (Table 3).
Table 3. Compa ison o he imp o emen in he hyd aulic ope a ion be ween he diagnosis and
he o ecas s o T = 10 yea s wi h clima e change (me e s I% o ne wo k).
S age F ee Flow
Unde
P essu e
0.5 m
Unde g ound
On he
G ound
Diagnosis wi h clima e
change
672,738.99
(35.68%)
623,618.43
(33.07%)
65,936.03
(3.50%)
523,364.89
(27.76%)
Fo ecas 1 lood (SUDSs) 780,700.27
(41.37%)
613,473.03
(32.51%)
62,135.15
(3.29%)
430,682.16
(22.82%)
Fo ecas 2 lood (SUDSs +
s uc u es)
1,580,857.56
(82.96%)
263,066.76
(13.81%)
14,301.25
(0.75%)
47,244.55
(2.48%)
I is also impo an o no e ha he g ea imp o emen in he ope a ion o he ne wo k
be ween he p ognosis 1 scena io and he p ognosis 2 scena io was no caused exclusi ely
due o he planned s uc u al ac ions, bu pa ly hanks o he hypo hesis conside ing ha
he loods in he seconda y ne wo k a e sol ed by inc easing he capaci y o he seconda y
ne wo k.
The ope a ion o he ne wo k was also analyzed, bu only o he main ne wo k in
o de o elimina e he e ec o he imp o emen in unc ionali y due o he inc ease in he
capaci y o he seconda y ne wo k in he o ecas scena io 2. Thus, i was e i ied ha
coun ing he o al o he ne wo k by T10 in scena io 1 esul ed in a 780 km ee low ne -
Figu e 12. Le el o damage in he exis ing ne wo k. PDISBA includes Le el 4 and 5 ixing.
Table 3.
Compa ison o he imp o emen in he hyd aulic ope a ion be ween he diagnosis and he
o ecas s o T = 10 yea s wi h clima e change (me e s I% o ne wo k).
S age F ee Flow Unde P essu e 0.5 m
Unde g ound On he G ound
Diagnosis wi h
clima e change
672,738.99
(35.68%)
623,618.43
(33.07%)
65,936.03 (3.50%)
523,364.89
(27.76%)
Fo ecas 1 lood
(SUDSs)
780,700.27
(41.37%)
613,473.03
(32.51%)
62,135.15 (3.29%)
430,682.16
(22.82%)
Fo ecas 2 lood
(SUDSs +
s uc u es)
1,580,857.56
(82.96%)
263,066.76
(13.81%)
14,301.25 (0.75%) 47,244.55 (2.48%)
I is also impo an o no e ha he g ea imp o emen in he ope a ion o he ne wo k
be ween he p ognosis 1 scena io and he p ognosis 2 scena io was no caused exclusi ely
due o he planned s uc u al ac ions, bu pa ly hanks o he hypo hesis conside ing ha
he loods in he seconda y ne wo k a e sol ed by inc easing he capaci y o he seconda y
ne wo k.
The ope a ion o he ne wo k was also analyzed, bu only o he main ne wo k in
o de o elimina e he e ec o he imp o emen in unc ionali y due o he inc ease in
he capaci y o he seconda y ne wo k in he o ecas scena io 2. Thus, i was e i ied
ha coun ing he o al o he ne wo k by T10 in scena io 1 esul ed in a 780 km ee low
ne wo k, while in scena io 2, his inc eased o 1580 km (an imp o emen o mo e han
double). In con as , by coun ing only he main ne wo k, he imp o emen was smalle ,
going om 227 o 377 km o he ne wo k unc ioning unde he ee low condi ion.
5.4.2. O dina y Hyd ological Scena io o CSO Analysis
Fo each o he o ecas scena ios ( o ecas 1 ela ed o SUDS implemen a ion and
o ecas 2 ela ed o implemen a ion o SUDSs + s uc u al measu es), he yea 2009 was
simula ed as a e age ain all o ob ain he olumes and he pollu ion caused by he
o e low poin s. In addi ion, a 3D ma ine model simula ed he wa e quali y o he ba hing
Sus ainabili y 2021,13, 71 18 o 25
wa e s in Ba celona du ing he ba hing season o 2009. The model aimed o es ima e he
impac o spills on ba hing a eas in e ms o wa e quali y s anda ds.
The esul s p esen ed he e (Table 4) allow o he conclusion ha he objec i e ega d-
ing he educ ion o pollu ion discha ged by bo h he Besòs i e and he po was achie ed,
al hough, in his case, he educ ion was smalle due o he ac ha many spills a e no
ela ed o he main CSO poin s.
Table 4.
Pe cen ages o he pollu ion educ ion discha ged in he wo CSO p ognosis scena ios wi h
espec o diagnosis.
S age Ou all A ea Volume SS BOD5 NH4+
Fo ecas 1
(SUDSs)
Po 19% 19% 19% 19%
Beaches 37% 37% 37% 37%
Besòs Ri e 23% 23% 23% 23%
To al 28% 28% 28% 28%
Fo ecas 2
(SUDSs +
s uc u es)
Po 37% 67% 66% 57%
Beaches 65% 74% 73% 71%
Besòs Ri e 58% 71% 70% 66%
To al 52% 71% 70% 64%
The aim o he adap a ion measu es o he en i onmen al impac was o ocus on
he educ ion in he pollu an discha ge and he impac on he ba hing wa e egula ions.
Figu e 13 shows he wa e quali y impac o he CSOs be o e he plan and a e he
applica ion o all measu es.
Sus ainabili y 2021, 13, x FOR PEER REVIEW 19 o 26
Figu e 13. Pe cen age o ime wi h low-quali y ba hing wa e s o Ba celona’s sho eline due o
CSOs. The esul s a e ou lined o e e y beach in he ci y.
5.5. 10-Yea Re u n Pe iod Damage Compu a ion
The esidual isk and an e ac ual isk we e bo h ans o med in o damage ollowing
he lood damage model de eloped in PDISBA. This s ep is necessa y o be able o pe o m
CBA. CBA is no used o ank measu es; ins ead, i is used o jus i y he p oposed in es -
men plan. The esul s a e p esen ed in Table 5.
Table 5. Flood and en i onmen damage o he di e en scena ios using he 10-yea e u n pe-
iod e en s. The concep o quan i y he lood impac is he expec ed annual damage (EAD).
Damage BAU (Business as Usual) SUDSs SUDSs + S uc u es
P ope y €44 million €23 million €2 million
Vehicles €4 million €2 million €0.34 million
Business in e up ion €13 million €7 million €0.73 million
En i onmen al €39 million €27 million €17 million
To al €100 million €59 million €20 million
6. Financial Analysis and In es men Planning
In his sec ion, he damage is ela ed o he in es men s, while inancial analysis is
applied o decide he alue o he p oposed mi iga ion measu es.
6.1. Summa ized In aes uc u e Cons uc ion Budge
Table 6 shows he adap a ion measu e budge , which o als €1422 million. In con as ,
he in es men associa ed wi h he en i onmen al impac (i.e., CSOs) is €206 million;
hence, he budge ela ed o lood managemen is €1226 million. The cos s we e es ima ed
h ough he p ices da abase o he Ci y Council, including all o he ci il wo ks de eloped
o e he las yea s. The o al olume o he planned s o m anks was abo e 1 million cubic
me e s, he cos pe cubic me e being app oxima ely 0.5 €/m3.
Figu e 13.
Pe cen age o ime wi h low-quali y ba hing wa e s o Ba celona’s sho eline due o CSOs.
The esul s a e ou lined o e e y beach in he ci y.
5.5. 10-Yea Re u n Pe iod Damage Compu a ion
The esidual isk and an e ac ual isk we e bo h ans o med in o damage ollowing he
lood damage model de eloped in PDISBA. This s ep is necessa y o be able o pe o m CBA.
Sus ainabili y 2021,13, 71 19 o 25
CBA is no used o ank measu es; ins ead, i is used o jus i y he p oposed in es men
plan. The esul s a e p esen ed in Table 5.
Table 5.
Flood and en i onmen damage o he di e en scena ios using he 10-yea e u n pe iod
e en s. The concep o quan i y he lood impac is he expec ed annual damage (EAD).
Damage BAU (Business as
Usual) SUDSs SUDSs + S uc u es
P ope y €44 million €23 million €2 million
Vehicles €4 million €2 million €0.34 million
Business in e up ion €13 million €7 million €0.73 million
En i onmen al €39 million €27 million €17 million
To al €100 million €59 million €20 million
6. Financial Analysis and In es men Planning
In his sec ion, he damage is ela ed o he in es men s, while inancial analysis is
applied o decide he alue o he p oposed mi iga ion measu es.
6.1. Summa ized In aes uc u e Cons uc ion Budge
Table 6shows he adap a ion measu e budge , which o als
€
1422 million. In con as ,
he in es men associa ed wi h he en i onmen al impac (i.e., CSOs) is
€
206 million; hence,
he budge ela ed o lood managemen is
€
1226 million. The cos s we e es ima ed h ough
he p ices da abase o he Ci y Council, including all o he ci il wo ks de eloped o e he
las yea s. The o al olume o he planned s o m anks was abo e 1 million cubic me e s,
he cos pe cubic me e being app oxima ely 0.5 €/m3.
Table 6. Summa y o he o al in es men in mi iga ion measu es de eloped in PDISBA.
Flood mi iga ion
measu es in he p ima y
ne wo k
S o m Tanks: 38 Uni s Equi alen o 1,017,400 m3€427,760,142
P ima y ne wo k
Replacemen o exis ing
condui s €13,261,471
New condui s €67,819,399
Hyd aulic s uc u es (wei s, spillways, and ga es) €6,643,490
To al €515,484,502 36%
CSO mi iga ion
measu es Fi s lush anks: 15 uni s, equi alen o 525,500 m3€206,248,046 15%
SUDS 182 Ha
In il a ion ench €85,509,743
Di e sion basins: 10 uni s, equi alen o 128,700 m3€12,870,000
G een oo €114,752,240
To al €213,131,983 15%
New gullies To al €83,520,104 6%
Seconda y ne wo k To al €208,005,077 15%
Ne wo k ehabili a ion To al €195,891,672 14%
TOTAL €1,422,281,384 100%
The SUDS in es men co esponds o 15% o he o al budge and i s de elopmen
will be in pa allel o o he u ban ci il wo ks.
Sus ainabili y 2021,13, 71 20 o 25
6.2. In es men Plan
The o al budge o he measu es planned in he PDISBA is app oxima ely
€
1500
million. The impac o his in es men on he economy o he ci y o ces o de elop an
in es men plan, easonable o he capabili ies o he Ci y Council. The ime span used in
he inancial analysis was 20 yea s o he implemen a ion o measu es and 80 yea s o
he li e cycle o he in as uc u es. The esidual alue was conside ed o compu e he ne
p esen alue (NPV) and he in e nal a e o e u n (RR) on in es men .
Table 7shows he planned in es men a e and compa es i wi h he ac ual a es. The
impac on he local economy is clea , and e ol es om an in es men a e o
€
14 million o
a new one o €45 million.
Table 7. In es men s a es in he nex 20 yea s o de elop he measu es planned in he PDISBA.
Budge Name To al Planed In es men
Ra e
Ac ual In es men
Ra e
Flood isk
managemen
in as uc u es
€500 million €25 million/yea €mllion/yea
CSO in as uc u es €200 million €10 million/yea €0 million/yea
SUDSs €200 million U ban planning U ban planning
Seconda y ne wo k €284 million U ban planning U ban planning
Rehabili a ion €195 million €9.6 million/yea €4.3 million/yea
6.3. In es men Ra ionaliza ion and Sus ainabili y
The o e all PDISBA budge , including he sus ainable u ban d ainage sys ems, con-
se a ion measu es, and ac ions o expand and imp o e he sewe age and d ainage sys em,
s ands a
€
1.4 billion. Tha is di ided in o
€
700 million o isk managemen and en i on-
men al p o ec ion measu es and
€
700 million on he local ne wo k and sus ainable u ban
d ainage sys ems. The budge is equi alen o app oxima ely 34% o he sys em’s he i age
alue, calcula ed a
€
4.6 billion. To pu i ano he way, he a e age age o Ba celona’s sew-
e age and d ainage sys em is 69 yea s, and i will equi e an in es men o app oxima ely
one hi d o i s asse alue o ackle he challenges o he nex 80 yea s in i s li espan. In
gene al e ms, he in es men plan, which s ems om he PDISBA’s o e all budge , means
an in es men a e o €175 million e e y 10 yea s.
The Ci y Council is cu en ly wo king on he block ela ing o in es men in isk
managemen and adap ing i o clima e change in he mos ulne able neighbo hoods by
means o he ollowing speci ic ac ions in he nex six yea s:
•
Di ision o he la ge A . de la Diagonal in e cep o , in he inal egula ed s e ch
be ween Ca e de Gi ona and Passeig de San Joan, o de end and p o ec he lowe
pa o G àcia, a ound he s ee s o Gi ona and Bailen—wi h an app oxima e budge
o €8 million.
•
The hi d phase o he A . Pa al
·
lel-Ca e Vila i Vila d ainage sha , in he i s
s age o Ca e Vila i Vila, o he de ense and p o ec ion o he neighbo hoods in he
con luence o Ciu a Vella, he lowe pa o Eixample Esque e, and Poble Sec—wi h
an app oxima e budge o €21 million.
•
Unde g ound egula ion ank o he ainwa e om he A . de P im d ainage
sha , o he de ense and p o ec ion o he La Sag e a a ea and he Besòs Ma esme
neighbo hoods—wi h an app oxima e budge o €55 million.
The e o e,
€
84 million—96% o he in es men en isaged unde he PDISBA in he
nex 10 yea s on he isk managemen and adap a ion o clima e change block—has al eady
been in es ed o he nex six yea s
Sus ainabili y 2021,13, 71 21 o 25
6.4. Cos –Bene i Analysis (CBA)
Due o he di e en ime spans and li e cycle du a ions o he in as uc u es planned,
he equi alen annual annui y (EAA) o he NPV was used o pe o m he CBA, labeled
as he annual equi alen p esen alue (AEPV). The a e o in e es used o he inancial
compu a ion was 1.23% [
42
], and he pe iod conside ed was 80 yea s, wi h an implemen-
a ion pe iod o 20 yea s. Fo he s uc u al measu es, he li e cycle was assumed o be
80 yea s, and o he SUDSs, 20 yea s was assumed. Meanwhile, he g een oo li e was
expec ed o be 70 yea s. The bene i was compu ed using he a oided damage, e alua ed
as he di e ence in he EAD [43] o he di e en scena ios.
The cos s used o he CBA included he implan a ion o measu es and he ope a ion
and managemen cos as well. In he case o s uc u es wi h smalle ime spans han he
analysis pe iod, ehabili a ion o e u bishmen was included in he cos .
As men ioned in he in oduc ion, he complexi y o he in e ac ions be ween manage-
men measu es did no pe mi o compu e hei e ec s independen ly. Mo eo e , i was
no possible o compu e he e ec o all combina ions; hence, wo g oups we e de ined as
sequen ial s eps:
1.
SUDS de elopmen : This scena io assumes ha all he SUDSs a e implemen ed in he
ci y.
2.
SUDSs + s uc u al measu es: This scena io occu s a e he p e ious one, in which
SUDSs a e inished and hen he s uc u al measu es a e implemen ed.
The Figu e 14 shows he esul s o he CBA when lood damage was conside ed. In
he ac ual scena io (i.e., business as usual (BAU)), he EAD was
€
63 million. A e applying
he SUDS plan, he EAD was educed o
€
39 million, wi h a cos o
€
10 million and a
bene i o €22 million.
Sus ainabili y 2021, 13, x FOR PEER REVIEW 23 o 27
Figu e 14. Resul s o he CBA o he isk managemen plan conside ing only he lood damage. AEE, annual equi alen
annui y; AEPV, annual equi alen p esen alue; EAD, expec ed annual damage.
When he s uc u al measu es we e applied, he EAD educed o €14 million, bu he
o al cos o he plan ose o €22 million pe yea . When he en i onmen damage was
analyzed o he CSOs, he annual damage was €4 million, and a e he SUDS plan, i
educed o €3 million/yea , and a e he s uc u al measu es ( i s lush anks), i educed
o €2.2 million. Figu e 15 shows hese esul s.
Figu e 15. Resul s o he CBA o he isk managemen plan conside ing only he en i onmen al damage.
The impac o SUDSs on lood and en i onmen al damage we e added, and he inal
esul s we e hen hen an SUDS implemen a ion cos o €10 million; when adding bo h
bene i s, he ne bene i was €32 million, which is he e o e he mos success ul measu e
in he plan. Howe e , o o e come i s limi a ion in e ms o impac , s uc u al measu es
a e manda o y.
BAU (Bussiness
As Usual) SUDS SUDS +
S uc u al
Annual EAD 63108344 39362159 14086518
Cos 9918794 22392823
AEE A oided damage 23746185 49021826
Bene i 32474983 57750624
AEE ne bene i 22556189 35357801
0
10
20
30
40
50
60
70
AEPV
(M€/any)
BAU
(Bussiness
As Usual)
SUDS SUDS +
S uc u al
En i onmen damage 41059536 31017845 22706969
Cos 9918794 16145628
Bene i 18997570 26996125
Ne bene i 0 9078777 10850497
0
5
10
15
20
25
30
35
40
45
AEPV
(M€/any)
Figu e 14.
Resul s o he CBA o he isk managemen plan conside ing only he lood damage. AEE, annual equi alen
annui y; AEPV, annual equi alen p esen alue; EAD, expec ed annual damage.
When he s uc u al measu es we e applied, he EAD educed o
€
14 million, bu he
o al cos o he plan ose o
€
22 million pe yea . When he en i onmen damage was
analyzed o he CSOs, he annual damage was
€
4 million, and a e he SUDS plan, i
educed o
€
3 million/yea , and a e he s uc u al measu es ( i s lush anks), i educed
o €2.2 million. Figu e 15 shows hese esul s.

Sus ainabili y 2021,13, 71 22 o 25
Sus ainabili y 2021, 13, x FOR PEER REVIEW 22 o 26
Figu e 14. Resul s o he CBA o he isk managemen plan conside ing only he lood damage. AEE, annual equi alen
annui y; AEPV, annual equi alen p esen alue; EAD, expec ed annual damage.
When he s uc u al measu es we e applied, he EAD educed o €14 million, bu he
o al cos o he plan ose o €22 million pe yea . When he en i onmen damage was
analyzed o he CSOs, he annual damage was €4 million, and a e he SUDS plan, i
educed o €3 million/yea , and a e he s uc u al measu es ( i s lush anks), i educed
o €2.2 million. Figu e 15 shows hese esul s.
Figu e 15. Resul s o he CBA o he isk managemen plan conside ing only he en i onmen al damage.
The impac o SUDSs on lood and en i onmen al damage we e added, and he inal
esul s we e hen hen an SUDS implemen a ion cos o €10 million; when adding bo h
bene i s, he ne bene i was €32 million, which is he e o e he mos success ul measu e
in he plan. Howe e , o o e come i s limi a ion in e ms o impac , s uc u al measu es
a e manda o y.
BAU (Bussiness
As Usual) SUDS SUDS +
S uc u al
Annual EAD 63108344 39362159 14086518
Cos 9918794 22392823
AEE A oided damage 23746185 49021826
Bene i 32474983 57750624
AEE ne bene i 22556189 35357801
0
10
20
30
40
50
60
70
AEPV
(M€/any)
BAU
(Bussiness
As Usual)
SUDS SUDS +
S uc u al
En i onmen damage 41059536 31017845 22706969
Cos 9918794 16145628
Bene i 18997570 26996125
Ne bene i 0 9078777 10850497
0
5
10
15
20
25
30
35
40
45
AEPV
(M€/any)
Figu e 15. Resul s o he CBA o he isk managemen plan conside ing only he en i onmen al damage.
The impac o SUDSs on lood and en i onmen al damage we e added, and he inal
esul s we e hen hen an SUDS implemen a ion cos o
€
10 million; when adding bo h
bene i s, he ne bene i was
€
32 million, which is he e o e he mos success ul measu e in
he plan. Howe e , o o e come i s limi a ion in e ms o impac , s uc u al measu es a e
manda o y.
7. Compa ison o PDISBA o he Cu en Plan
The new u ban d ainage Mas e Plan (i.e., he PDISBA) was compa ed o he cu en
plan in o ce (PICBA). Table 8shows he main g oups o he lood isk mi iga ion measu es
included in bo h plans. The pe cen age o di e ence, compu ed using he old plan alue as
a e e ence, is p esen ed in he hi d column o he able.
Table 8. Compa ison be ween he cu en plan and he new plan.
MEASURE PICBA (2006) PDISBA (2019) DIFF.
Flood mi iga ion
measu es in
p ima y ne wo k
S o m anks €181 million €428 million 136%
P ima y ne wo k
Replacemen o
exis ing condui s €12 million €13 million 8%
New condui s €101 million €68 million −32%
Hyd aulic s uc u es (wei s, spillways,
and ga es) €1 million €7 million 600%
CSO mi iga ion
measu es Fi s lush anks €203 million €206 million 1.5%
SUDSs
In il a ion ench - €86 million -
Di e sion basins: 10 uni s, equi alen o
128,700 m3-€13 million -
G een oo - €115 million -
New gullies Gullies €32 million €84 million 150%
Seconda y
ne wo k Condui s €184 million €208 million 13%
Ne wo k
ehabili a ion Condui s - €196 million -
Sus ainabili y 2021,13, 71 23 o 25
The SUDS in es men could no be di ec ly compa ed because i is a new elemen
in he budge . In he p e ious plan equi emen s, he e we e no e e ences o sus ainable
d ainage, being one o he main di e ences be ween he plans ega ding he s uc u al
measu es. In con as , a SUDS is a sys em o educe he di ec uno o he p ecipi a ion,
hence i is linked o he impac o loods and clima e change. The e o e, i s budge was
included in he compa ison o cos s.
A simila si ua ion occu ed o he ne wo k ehabili a ion plan, which was ecen ly
inished in he amewo k o he new plan. Ex ending he li e cycle o in as uc u es is a
equi emen o he new plan. Hence, he e is no di ec compa ison wi h he p e ious plan,
bu in his case, i is an elemen no ela ed o loods. The budge de o ed o ehabili a ion
is high, because ne wo k diagnosis e ealed a poo main enance condi ion.
The in es men o he i s CSO lush anks is simila in bo h plans, and i is mainly
ela ed o en i onmen al issues, no o clima e change o loods. The physical loca ions o
he anks, a ound he sho eline, educe i s impac on lood managemen ; hence, clima e
change and CSOs a e decoupled om a measu es poin o iew.
Mo eo e , he seconda y ne wo k in es men budge is qui e simila in bo h plans
and is no ela ed o clima e change because i is mainly alloca ed o he de elopmen o
new u ban a eas. The di e ence obse ed in he new condui s alue is jus i ied because
some o he measu es p oposed in he old plan ha e al eady been cons uc ed du ing his
pe iod o he new plan. In case o s o m anks, he PICBA plan conside s mo e han 50
anks, and jus 20% o hem ha e been cons uc ed. S o m anks ha e a di ec impac on
lood con ol, and hence hey should be added o he inal compa ison.
The o al budge , including all he measu es (en i onmen al, loods, and ope a ion)
was
€
714 million o old plan (PICBA) and
€
1424 million o he new plan (PDISBA), bu
hese alues could no be asc ibed o clima e change impac s, as desc ibed p e iously.
The e o e, hese alues should be il e ed.
Conside ing all o he p e ious assump ions, he calcula ion used o compa e he
budge o add ess he impac o clima e change- ela ed loods was SUDSs + Hyd. Es . +
condui s + s o m anks. The o al budge o he old plan (PICBA) was
€
295 million and
€
730 million o he new plan (PDISBA), wi h he di e ence be ween bo h plans being
€
435
million. This di e ence is mainly ela ed o he cons uc ion o he s o m anks, wi h and
in es men inc emen o
€
245 million. The second pa o he di e ence is a esul o he
SUDSs ecei ing an in es men highe han €150 million.
The e o e, i can be concluded ha unde he new ain all scena io, including clima e
change, he new lood managemen measu es o al cos is 147% highe han he old one.
8. Conclusions
Clima e change has an impo an impac in u ban d ainage mas e plan budge ing.
P e ious plans become ou da ed due o he e olu ion in he ain all scena ios. I he e u n
pe iod is used in he design c i e ia, upda ing he ain all scena ios in ol es adding ex a
s uc u al measu es o he p e ious plans.
Ba celona Ci y Council de eloped i s In eg al D ainage Mas e Plan (PDISBA), wi hin
which, i included he de ini ion o new ain all e en s linked o he RCP 8.5 clima e change
scena io. The o al cos o he p oposed measu es eached
€
1.4 billion. In o de o jus i y
his in es men , a CBA was pe o med.
To analyze he impac o he measu es, an 80-yea pe iod was conside ed. The du a ion
o he implemen a ion o he s uc u al measu es was 20 yea s. Due o he di e en ime
spans o he in as uc u es, an equi alen annual annui y was used. Two measu e g oups
we e p oposed, he i s included SUDS implemen a ion and he second included s o m
anks, i s lush anks, and condui s o he han he SUDSs. Hence, he second scena io
was he second s ep a e he de elopmen o he i s scena io, bo h being sequen ial.
Rega ding he impac , loods and en i onmen al losses we e included in o de o
quan i y he impac o loods is he EAD. To achie e his alue, i was necessa y o compu e
di e en e u n pe iods. The esidual isk ela ed o bo h measu e scena ios was used o
Sus ainabili y 2021,13, 71 24 o 25
ee alua e he EAD and o compu e he bene i s. The annual bene i o he i s g oup o
measu es was
€
32 million/yea o loods and
€
19 million/yea o en i onmen losses.
Rega ding he second g oup o measu es, including s uc u es, he ne bene i o loods
ose o
€
57 million/yea and o en i onmen al losses, i inc eased o
€
26 million/yea .
Thus, he o al cos o he i s measu e scena io was
€
10 million/yea and o he second
measu e scena io, i was €22 million/yea .
Compa ing he new and old plans, he budge de o ed o loods has inc eased by
150%, om
€
295 million o
€
730 million. The ain all scena io igge ed he inc ease, i s
main di e ences being he peak in ensi y due o clima e change and he o al du a ion.
Au ho Con ibu ions:
Concep ualiza ion, A.O. and V.M.; me hodology, O.E., B.R. and M.J.V.;
so wa e, O.E. and M.J.V.; alida ion, V.M. and A.O.; in es iga ion, B.R. and M.J.V.; w i ing—o iginal
d a p epa a ion, V.M.; w i ing— e iew and edi ing, V.M.; isualiza ion, O.E., M.J.V. and A.O.;
supe ision, V.M.; p ojec adminis a ion, A.O.; unding acquisi ion, A.O. All au ho s ha e ead and
ag eed o he published e sion o he manusc ip .
Funding: This esea ch was unded by he Ba celona Ci y Council, con ac numbe E18-0185.
In o med Consen S a emen : No applicable.
Da a A ailabili y S a emen : Da a a ailable on eques due o es ic ions.
Con lic s o In e es : The au ho s decla e no con lic o in e es .
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