Water System Seismic Study and
Emergency Response Planning
Cascade Water Alliance meeting
06/09/2017
Agenda
•
•
•
2
Background
─ Water systems and planning for seismic events
Current State
─ Seismic study
─ Emergency response
─ Establish “service level goals” after a major earthquake
─ Balance goals vs. available funding
Looking Forward
─ Plan short-term and long-term infrastructure
seismic upgrades as part of Capital
Improvements Program
Earthquake Hazards
Ground Shaking
Fault Rupture
Earthquake Hazards
Liquefaction
Earthquake Hazards
Landslide
Tsunami
Importance of Water Post-EQ
•
•
•
Fire fighting
Sanitation
Consumption
Water is an
essential lifeline
Some Recent Earthquakes and
Water System Impacts
Year
Magnitude
Loma Prieta, Bay
Area
1989
6.9
Northridge, So. Cal
1994
6.7
Kobe, Japan
1995
6.9
Christchurch, NZ
2011
6.2
Tohoku, Japan
2011
9.0
7
Impacts
Nisqually Earthquake - 2001
Nisqually Earthquake Pipeline Damage
Bi t t er
L ake
Hall er
Lake
â
12T H AV S
S MCCLELLAN ST
a
TA
T
AV
L
KI
E
S SPOKANE S T
36T H AV S
31ST AV S
N
RB
O U T B A KE
S SPOKANE ST
NIE
RA I
DU
SW
WEST SEATTLE FRWY
W
IS
O
LU
MB
I AN
38T H AV S
S ALASKA ST
YS
WY
W
ORT
ON
ST
A I RP
WS
V
S
S HUD SON ST
DA
Y
4T H AV S
W
C
u
E MARGINAL WY S
SW
P
IAL
N AV S
US
TR
BEACO
SW
WY
SW
â
Watershed
Produced by the City of Seattle
June 27, 2001
THE CITY OF SEATTLE, 2001. All rights reserved
No guarantee of any sort implied, including accuracy,
completeness, or fitness for use.
j:\wocc\robin\arcviewfiles\eq_pipeline_damage.apr: nisqually earthquake pipeline damage
Chester Morse Dam
sloughing
AV S
S
N AV
S
TON AV
C ARLE
ELLIS
13T H AV S
6T H AV S
CO RSO
Water Bodies
Y
RD
ST
S
O
BR
AL
PL
S
Liquefaction Areas
HA
S GRAHAM ST
S
Water Reservoirs
S
AV
Transmission Mainlines
ST
Y
Legend
Water Leaks
LEY
ST
JR WY
AN
â
M L KING
S BAI
HIG
LE
S MIC
AN
ST
16TH AV SW
S LUCILE S T
â
R
S
AV
AL
Eastside RES
damages
â
S IND
GIN
t
g e
H
SW ANDO V E R ST
A
R
AM
W MAR
â
â
NI
E
H UNTER BV S
IC
AN
EL
15T H AV S
6T H AV S
k
KL
CH
SW
S
S HORTON ST
ST
SM
ââ
DR
â
S HANFORD ST
S MASSACHUSETTS ST
LA K E PA RK
DR S
S LANDER ST
S F OREST ST
SW HANF ORD ST
35T H AV S
20T H AV S
S WALKER ST
S COLLEGE ST
V
ALASKAN FY
11T H AV SW
16TH AV SW
S PLUM ST
17T H AV S
â
1ST AV S
IDA ST
AI
ââ
â
â
FLOR
R
MT
ââ
â
S HOLGATE ST
SW
ING JR W Y S
ML K
â
Elliott Bay
S JUDKINS ST
S MASSACHUSETTS ST
TWY S
a s h i n g t o
n
e W
Lake
Union
24T H AV S
GO
LF
P OR
AIR
â
â
S ATLANTIC ST
26T H AV S
S DEA RB ORN ST
â
3 5TH A V S
â
S ROYAL BROU GHAM WY
S
DR
â
S
LAKESIDE A V S
YS
â
PL
MAYNARD AV S
DW
OA
SoDo/Duwamish Area
IN E
5T H A V S
2N D AV
EF
ON
TA
ILR
RA
â
14T H AV S
PR
Green
Lake
7T H AV S
S o
u n
d
â
â
• Magnitude 6.8, centered
near Olympia, 32 miles
deep
• Minimal effect on SPU
functionality
• Approximately $4 million in
earthquake related costs
• Masonry Pool
Engineered Fill Failure
• 12 Pipe breaks and 7
pipe leaks
• 500 Ft. Long, ½-Inch
wide crack in
Cascades Dam
Nisqually 2001 (con’t)
• Tolt East Side Supply Line
Junction Valve Station damage
• SPU Admin Bldg (Dexter Horton)
nonstructural damage
• Eastside Reservoir floor cracks
and roof damage
• Operations and Control Center
Damage
SPU History of Seismic Work
•
Working on seismic issues for several decades
─ Various studies
─ Seismic retrofits
─ Incorporation of
then-current seismic
standards into new
facilities
SPU History of Seismic Work
•
Regional
collaboration with
other water utilities
Better Understanding of Seismic Risks in
Puget Sound – 1990 vs. 2015
Better Understanding of Seismic Risks in
Puget Sound – 1990 vs. 2015
Emergency Response
•
•
•
Response depends on type of emergency
─ Can vary widely
Water system redundancies can help with response
times
Triage based on available data
─ SCADA
─ Rapid post-disaster assessment from SPU crews, engineers
─ Calls from other utilities, customers
─ Other?
Pacific Northwest Earthquake Sources
(Washington State Department of Natural Resources and USGS)
SPU Water System Seismic Study
•
•
•
•
Establish post-earthquake water system
performance goals
Seismic vulnerability assessments of facilities and
pipes
Balance performance goals against cost of
upgrades
Develop short-term (20 year) and long-term (50+
year) plans
─ Integrate plans into Capital Improvement Program
Balancing Performance Goals and
Seismic Improvement Needs
• Consultant Recommendations
• Cost Considerations
Post-Earthquake Performance Goals
Cost to Achieve Performance Goals
• This approach is typical of other
water utilities
Stakeholder Input is Critical to
Developing Performance Goals
•
•
•
•
Public/Direct Service Customers
─ Water System Advisory Committee
─ Customer Review Panel
─ Surveys
Wholesale Customers (Operating Board, Cascade
Water Alliance)
City Leadership
─ Mayor/Council
─ Fire Department
─ SPU
─ Emergency Executive Board
SPU Staff
Draft Performance Goals
•
•
•
•
Water supply for fire fighting
Water supply for critical facilities like hospitals
Water supply for retail customers
Water supply for wholesale customers
How long should it take to achieve these goals for what
% of the water system?
What Kinds of Upgrades Will Be Needed?
Next Steps
•
•
•
Proposed mitigation options
Review cost of options and see if performance
goals need to be changed
Study complete in 2017
─ Use results to develop short-term and long-term seismic
recommendations
─ Fold into rest of Capital Improvement Program
Questions/Discussion
Extra Slides to Follow
Loma Prieta (San Francisco) - 1989
• M6.9 (epicenter 60 miles
south/southeast of San
Francisco)
• Approximately 1000
watermain breaks
• Water system damage
mostly in areas of poor
soils
• Water outage
durations usually
less than a few days
• Fire suppression
water was an issue
in Marina District
Marina District 1912
Northridge - 1994
• M6.7 (previously
unknown fault)
• Over 1000 watermain
breaks
• Over 100 fires
• Water system damage
mostly in areas of poor
soils
• Outage durations over 8
to 13 plus days
Kobe (Hyogo-Ken Nanbu) – 1995 (M6.9)
• Over 1700 Pipe Breaks Just in Kobe
• 109 Kobe Fire Ignitions Immediately After
Earthquake (Another 88 in Surrounding Cities)
• 60 Days Plus for Restoration of Service
Earthquake
(January
17)
“Substantial” Restoration
(March 18)
2011 Christchurch Earthquake (M6.2)
• 1645 Watermain Breaks (February 2011
Earthquake) in Christchurch
• Limited Number of Fire Ignitions
• 45 Days Plus for Restoration of Service
Most of pipeline system
restored (end of March)
FEB 22
(Earthquake
)
Water Treatment
Restored (mid April)
Tohoku (East Japan) – 2011 (M9.0)
• Water Systems of Over 180 Municipalities Affected
• 345 Fire Ignitions
• 45 Days Plus for Substantial Restoration of Service
Houses
Restored
“Substantial”
Restoration (74,000
Houses WithoutHouses Without
Water) – May 1
Earthquake Water
(March 11)
Sendai Pipe Breaks (red dots)
SPU Seismic Mitigation Program History
• Seismic Reliability Study
of the Seattle Water
Departments Water
Supply System (Cygna
Energy Services, 1990)
• Earthquake Loss
Modeling of the Seattle
Water System (Kennedy
Jenks Chilton/USGS,
1990)
SPU Seismic Mitigation Program History
(continued)
• SPU Seismic Upgrade
Program (e.g., OCC,
Myrtle Elevated Tanks,
Barton Standpipe, etc.)
• Performance of Water
Supply Systems in the
February 28, 2001
Nisqually Earthquake
(system post-earthquake
hydraulic modeling, Water
Research Foundation,
2008)
Picture of SPU upgrade
such as myrtle elevated
tanks goes here
What’s Changed (since 1990)
• Active surface faults identified
throughout Puget Sound
region (e.g., Seattle Fault,
South Whidbey Island Fault,
Tacoma Fault, etc.)
• Migration from 10%
probability of exceedance in
50 years (475 year return
interval) design earthquake to
2% probability of exceedance
in 50 years (2475 year return
interval) design earthquake
What’s Changed (since 1990 - continued)
• Earthquake Experience
(e.g., Northridge,
Japanese, Chilean and
New Zealand events)
• Potential for mass
availability of earthquakeresistant pipe in U.S.
Post-Earthquake Water System Performance
Goals
• Define water availability and water service
restoration time after an earthquake
• Purposes
– Establish acceptable water system post-earthquake
performance
– Define seismic program objectives
– Provide others with expected system performance so
they know what to expect and prepare for
SFPUC Performance Goals
• “The basic “Level of Service” criterion shall be to
deliver winter day demand (WDD) of 215 million
gallons per day (MGD) (February 2030 demand)
within 24 hours after a major earthquake.
• Deliver WDD to at least 70% of SFPUC
wholesale customers’ turnouts within each of the
three customer groups (Santa
Clara/Alameda/South San Mateo County,
Northern San Mateo County, and City of San
Francisco).
• Achieve a 90% confidence level of meeting the
above goal, given the occurrence of a major
earthquake.
EBMUD Performance Goals
Oregon Resiliency Plan Performance Goals