Floodproofing techniques for risk mitigation in urban areas · Floodproofing techniques for risk...
37
1 Floodproofing techniques for risk mitigation in urban areas CWS Seminar Series 2018/2019 Exeter, 13 th May 2019 Prof. Giuseppe T Aronica Department of Engineering, University of Messina, ITALY
Transcript of Floodproofing techniques for risk mitigation in urban areas · Floodproofing techniques for risk...
1
Floodproofing techniques for risk mitigation in urban areas
CWS Seminar Series 2018/2019Exeter, 13th May 2019
Prof. Giuseppe T AronicaDepartment of Engineering, University of Messina, ITALY
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.2
Outlines
The new policy of flood risk management is to give more attention to
non-structural measures, allowing people to “living with floods” rather
than “fight against floods”.
Floodproofing can be defined as combination of structural and non-
structural changes, or adjustments made in the building that reduces or
prevents flood damage to the structure and/or its contents.
The talk will presents and discuss the most common flood proofing
techniques for urban flooding risk mitigation
Presentation will also deal with a practical application of these measures
by showing the results for a case study in the city of Barcellona, Sicily,
Italy which suffered a severe inundation in November 2011.
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.3
Messina, 16 June 2018
Urban flooding
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.4
Catania, 9 September 2015
Urban flooding
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.5
UK, various locations
Urban flooding
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.6
Urban flooding events in urban areas more frequent than floods in natural areas even in case of correct drainage network dimensioning.
Further, very often these flooding involve small portions of urban areas (“patchy flooding”)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.7
0
0.05
0.1
0.2
0.4
0.6
0.8
1
T = 20 years
Probability
1
Genoa
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.8
R H V E
The variables of risk equation
€T
h h
Dam
age
%
Fighting against the floods Living with the floods
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.9 Risk mitigation
Highlights in urban flood risk
Patchy flooding
Difficulties in implementing large flood defense systems(high costs, environmental impacts)
High frequency and fast events
Rapid implementation mitigation measures
Increasing resilience
Tailored to protecting sensitive buildings (i.e., hospitals..)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.10
Floodproofing
Floodproofing is defined as combination of
structural and non-structural changes, or
adjustments made in the building that reduces or
prevents flood damage to the structure and/or
its contents. It can also be stated as any
structural or non-structural measures intended
to prevent damage from flooding to a building.
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.11
USACE publications, 1995
http://www.publications.usace.army.mil/
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.12
https://www.fema.gov/media-library-data/9a50c534fc5895799321dcdd4b6083e7/P-936_8-20-13_508r.pdf
FEMA (Federal Emergency Management Agency, 2013)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.13 Floodproofing
Surface Water Management Plan, Environmental Agency, UK 2009
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.14
Floodproofing
Wet proofing Dry proofing
• Raise the buildings
• Use of water-resistantmaterials
• Elevate the electricalcomponents and the inventory
• Valves for against backwater efects
• Sealing openings and walls (SEALING)
• Use of flood barriers, installed at the entrance of the buildings (SHIELDING)
• Flood barriers along riverbanks or crossing a street (SHIELDING)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.15
Flood proofing
Elevate the electrical components and the inventory
WET FLOOD PROOFING
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.16
Floodproofing
DRY FLOOD PROOFING
Sealing openings and walls (SEALING)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.17
Flood proofing
DRY FLOOD PROOFING
Use of flood barriers, installed at the entrance of the
buildings (SHIELDING)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.18
Flood proofing
DRY FLOOD PROOFING
Use of flood barriers, installed at the entrance of the
buildings (SHIELDING)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.19
Flood proofing
DRY FLOOD PROOFING
Use of flood barriers, installed at the entrance of the
buildings (SHIELDING)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.20
Sealing openings and walls & closing openings (SEALING+ SHIELDING)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.21
Flood proofing
DRY FLOOD PROOFING
Flood barriers along riverbanks or crossing a street (SHIELDING)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.22
Flood proofingDRY FLOOD PROOFING
Flood barriers along riverbanks or crossing a street (SHIELDING)
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.23
A real case application
Flood barriers are easier and quicker to install and are easier to remove. These flood protection ought to have an acceptable stability against
overturning and sliding
With excellent results, these barriers are commonly used in many parts of the world, especially in North Europe because there are typically
affected by clear water floods and therefore they can easily withstand the hydrodynamic forces
In some situations, like Mediterranean areas, water floods are full of sediments and flows very fast.
Is stil possible to use “normal” flood barriers to reduce and mitigate risk?
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.24 Case study
Area (km 2 ) 1,297
Main branch (km) 2,6
Mean elevation (m) 318
Max elevation (m) 581
Min elevation (m) 54
Area (km2) 32
Main branch (km) 13.4
Mean elev. (m) 400
Max elev. (m) 1162
Mean slope (m) 0.18
LONGANO CATCHMENT
Barcellona
Barcellona, 22 November 2011
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.25 Case study
0
50
100
150
200
250
300
350
400
0
20
40
60
80
100
120
140
Cu
mu
late
d r
ain
fall
(mm
)
10-m
in r
ain
fall
inte
nsi
ty (m
m/h
r)
time on 22/11/2011
0
50
100
150
200
250
0
10
20
30
40
50
60
70
80
90
100
Flo
od
dis
cha
rge
(m3/s
)
10
-min
ra
infa
ll in
ten
sity
(m
m/h
r)
time on 22/11/2011
Rainfall
Discharge
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.26
Barcellona, 22 November 2011
Case study
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.27
Choose of the location for the flood barriers
Simulations with a hydrodynamic
model (MLFP-2D)
Hydrodynamicverification
Final choice of flood barriers
Case study
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.28
K3
K45
K2
K2
K1
K3
K44
K2
K43
K1 K1
K43
K42
BASTIONE
PEZZA DEL
PIOPPO
CALDA'
P O N T E C A L I F E
F I L I C U S A
TORRENTE
MELA
TORRENTE
LONGAN
O
T.
IDR
IA
TORRENTE
IDRIA
CAMICIAMADONNA
DELL'ACQUA CALDA
CONTRADA
PETRARO
CASE LONGO
BARCELLONA
POZZO DI GOTTO
P O Z Z O
D I
P E R L A
C O N T R A D A
S I E N A
CONTRADA
MAURO
BARTOLELLA
CONTRADA
CAVALIERE
C O N T R A D A
M A N N O
C R O C E F I S S O
C O N T R A D A
M A L A N D R I N O
C O N T R A D
A
P A V A N O
PO
ZZO
CALIR
I
MELITICASE
CONTRADA
MOLINO
SANT'ANTONINO
SCARPACIAIA
DUCI
CALDERA'
ROCCOSAN
C. PANTE'
ACQUACALDA
C. SIENA
CRISAFULLIC.
RAGAZZI
CITTA'
DEI
RISICAMONTE
SA
IA
BIZ
ZA
RR
O
SA
IA
DE
LL'A
CQ
UE
DO
TTO
FER
RO
VIA
F.S
.
PA
LER
MO
ME
SS
INA
A20
MESSINA
PALERMO
AUTOSTRADA
S.P.
N.76
N.75
S.S
.
N.74
S.P.
CASELLO
6050
5045
5046
5397
5398
110.2
55.5
58.7
60.2
55.2
49.1
40.9
46.1
45.8
57.1
48.3
40.4
42.3
37.4
42.2
34.3
34.3
32.2
32.5
32.5
48.1
42.9
51.7
86.0
47.7
49.0
42.2
43.0
30.3
37.4
44.0
33.9
34.6
42.2
34.3
37.5
33.8
44.5
38.7
41.5
39.3
38.6
39.5
29.0
33.3
39.6
27.0
28.1
37.7
31.8
24.1
28.4
25.7
39.5
26.9
27.8
24.9
33.3
26.3
33.4
25.1
37.4
36.9
39.4
34.0
31.7
36.1
45.8
33.7
36.2
40.6
34.0
37.0
25.6
21.3
29.1
25.9
27.1
27.5
26.1
29.6
26.3
19.7
17.0
14.7
25.7
21.7
22.9
23.9
17.1
13.2
15.8
14.9
27.4
28.4
20.4
23.1
18.7
32.7
34.0
36.1
28.4
30.8
32.2
26.1
34.4
9.5
3.3
4.0
4.4
6.2
4.8
6.2
7.0
13.0
10.4
9.4
9.1
10.4
10.1
7.3
11.5
15.7
15.4
9.7
7.9
7.3
14.1
3.4
3.8
7.8
15.6
5.0
5.2
4.7
4.3
6.4
3.9
6.5
5.4
23.1
10.1
7.1
8.1
20.3
11.0
7.4
6.2
8.0
6.7
9.5
17.5
20.2
10.7
17.7
25.6
16.6
14.3
18.1
29.5
22.3
27.9
32.6
33.2
18.7
17.9
21.9
19.1
27.7
23.0
20.3
25.1
34.4
34.0
35.0
29.9
29.5
28.5
33.0
32.9
28.3
30.6
45.7
39.2
36.6
35.0
23.6
29.6
32.0
42.6
34.7
38.9
34.9
42.7
39.1
32.7
33.3
28.4
29.5
36.4
46.2
33.5
33.5
28.1
20.7
23.5
19.6
14.9
14.6
19.7
17.6
22.3
18.3
24.3
33.4
23.9
24.9
22.5
27.8
15.6
13.3
14.5
9.9
10.7
16.8
13.7
11.8
13.8
9.8
6.99.8
41.4 45.8
48.7
46.2
53.1
58.7
62.6
63.0 63.945.6 121.7
114.4
73.8
70.9
24.8
29.7
26.2
37.535.8
38.6
40.3
42.5
39.8
44.3
45.0
39.2
40.2
37.9
37.8
32.6
29.5
24.7
29.7
31.0
39.9
39.3
35.0
31.6
40.6
94.6
106.1
89.5
46.2
47.2
78.4
77.0 63.9
47.0
54.3
39.9
47.7
50.5
68.0
98.6
57.5
66.8
41.4
46.7
52.8
29.6
44.8
45.8
48.3
55.8
95.7
105.8
107.7
93.2
134.0
47.0
51.7
54.0
55.6
56.7
61.5
60.1
65.6
46.2
46.0
49.0
47.0
53.2
56.1
56.1
52.5
51.7
54.6
56.2
52.9
50.8
47.8
62.0
56.5
59.9
61.8
65.5
66.3
89.2
69.4
66.4
64.5
62.6
58.4
58.6
59.7
103.8
91.2
54.7
45.7
46.2
44.3 44.4
46.9
81.9
47.4
49.2
55.8
72.2
65.3
84.9
100.3
71.8
93.0
81.8
97.0
122.4
125.5
65.2
66.5
62.5
68.6
64.9
70.9
73.8
63.0
73.8
74.4
87.6
91.9
88.9
93.2
122.8
112.5
115.5
139.6
133.0
152.9
123.1
163.9
52.2
44.5
88.7
42.7
109.7
125.7
81.3
77.071.0
73.0
128.3
122.180.6
86.4
93.2
97.0
164.6
141.4
97.196.0
50
100
150
100
K1
K0
K1
SETTENTRIONALE
SICULA
T E L E F O N
O
TORRE
LUNGA
BORRACCIO
S.P
.
N. 7
6
MONTE
CROCI
CHIESA
CAPPUCCINI
S A N T ' A N N A
IL CARMINE
VILLA
BONOMO
CASA
RISAFI
TO
RR
EN
TE
IDR
IA
S.P
.
BARCELLONA
ZIGARI
NASARI
S E R R O
F E O
RAC
CO
RD
O
K2
Case study
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.29
Case study
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.30 Case study
Flood inundation and propagation in the city were modeled using a 2D hydraulic modelbased on De Saint Venant equations previously calibrated using the observationsconcerning water depths and flow velocities.
2538000 2538500 2539000 2539500 2540000
4219500
4220000
4220500
4221000
4221500
4222000
4222500
4223000
K1
SCARPACIAIA
5046
49.1
40.9
46.1
48.3
40.4
42.3
37.4
42.2
45.7
39.2
36.6
35.0
32.0
42.6
34.7
38.9
34.9
42.7
39.1
36.4
46.2
41.4 45.8
48.7
46.2
53.1
45.6
5087
42.5
39.8
44.3
45.0
39.2
40.2
37.9
37.8
63.9
47.7
50.5
68.0
140.8
98.6
66.8
135.5
81.5
131.2
139.7
144.3
113.0
172.8
174.8
159.2
104.4
44.8
45.8
48.3
55.8
95.7
105.8
107.7
93.2
134.0
144.0
139.4
134.3
123.2
100.0
105.2
47.0
51.7
54.0
55.6
56.7
61.5
60.1
65.6
75.8
73.2
70.9
82.0
85.0
83.2
46.2
46.0
49.0
47.0
53.2
56.1
56.1
52.5
51.7
54.6
56.2
52.9
50.8
47.8
62.0
56.5
59.9
61.8
65.5
66.3
70.9
83.9
89.2
69.4
76.7
80.9
85.286.6
89.9
88.1
83.1
79.3
77.2
78.2
81.6
79.1
71.3
66.4
66.5
64.5
62.6
58.4
58.6
59.7
103.8
91.2
54.7
45.7
46.2
44.3 44.4
46.9
81.9
47.4
49.2
55.8
72.2
65.3
84.9
100.3
71.8
93.0
81.8
97.0
124.6
106.0
65.2
66.5
62.5
68.6
64.9
112.7
115.4
70.9
63.0
74.4
87.6
91.952.2
120.681.7
73.6
72.9
68.8
75.7
109.1
155.3
151.1
149.8
157.1
171.8
193.4
182.9
191.4
85.0
163.7
140.5106.7
101.1
107.9
139.8
80.2
44.5
88.7
42.7
164.2
206.6
221.3
203.7
217.4
177.2
125.0
126.4
133.5
123.1
127.2
93.8
94.8
100.7
108.5
100.4
117.8132.8
100
150
100
150
20
0
150
100
150
200
150
K0
K1
K2
K3
S.P
.
N. 7
6
MONTE
CROCI
CHIESA
CAPPUCCINI
S A N T ' A N N A
BARCELLONA
POZZO DI
GOTTO
IL CARMINE
S.P
.
BARCELLONA
SAN
SAIA
SANTA
VENERA
SANTA VENERA
DEL PIANO
ZIGARI
NASARI
S E R R O
M I R A N D A
M O A S
D U
E
M U
L I N I
F E O
N. 8
2
LO
NG
AN
O
0.3
0.8
1.3
1.8
2.3
2.8
3.3
3.8
4.3
4.8
5.3
0.2 to 0.5
0.5 to 1
1 to 1.5
1.5 to 2
2 to 2.5
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.31
Case study
Simulations have been carried out with flood barriers of
different heights, to find the optimum height, to prevent
overtopping.
The force acting on the barriers was calculated combining the
classical equations for hydrostatic and hydrodynamic
force on a plane surface along a vertical wall:
The forces resulted from the model have been compared
with the stability values of the barriers provided by the
producers.
Hydraulic and static verification
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.32
FLOOD PANEL (U.S.A.)
FLOOD BREAK
(U.S.A.)
GEODESIGN
BARRIERS
(SWEDEN)
DUTCHDAM
(NETHERLANDS)
Case study
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.33
Maximum flood force2353 N/m
Final results
Maximum resistance (N/m)
Flood Panel Flood Break Geodesign Barriers
6075 18564 3900
For 3 feet height barriers
• Purchasing and installation costs for Geodesign barrier are around500 euros per meter• The intervention will be implemented for 12 meters (road width)
with a final cost of 6000 euros
Case study
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.34
Case study
Comparison of water depths values, before and after the intervention
0 2 4 6 8 10 12 14 160
0.1
0.2
0.3
0.4
0.5
0.6
0.7
distance(m)
heig
ht
of
wate
r(m
)
without flood barriers
with flood barriers
0 2 4 6 8 10 12 14 160.2
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
0.65
distance(m)
heig
ht
of
wate
r(m
)
without flood barriers
with flood barriers
0 2 4 6 8 10 12 14 160.2
0.25
0.3
0.35
0.4
0.45
0.5
distance(m)
heig
ht
of
wate
r(m
)
without flood barriers
with flood barriers
SectionA-A
SectionB-B
SectionC-C
hflood barriers = 1.25 m
Final results
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.35
Velocity vectors without flood barriers Velocity vectors with flood barriers
Case study
Velocity fields
Final results
G.T
. Aro
nic
a -
Flo
od
pro
ofi
ng
tech
niq
ues
fo
r ri
sk m
itig
ati
on
in…
.36
Conclusions
The new policy of flood risk management is to give more attention to
non-structural measures, allowing people to “live with floods” rather
than “fight floods”.
Floodproofing can be defined as combination of structural and non-
structural changes, or adjustments made in the building that reduces or
prevents flood damage to the structure and/or its contents
Road bariers sasy to implement with low costs
Suitable also for fast flowing flooding events
Need to use detailed hydrodynamic model for barriers design
Thank you for your attention([email protected])
