The 11th International Symposium
on Water Supply Technology

SFPUC Water System Improvements
to meet Levels of Service

July 10, 2019
San Francisco Public Utilities Commission (SFPUC)Sam Young, P.E.

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Outline• SFPUC Water System Overview• Water System Improvement Program (WSIP)o Level of Service Goals
o Key Projects• SF Water System Overview
o Level of Service Goals
o Pipeline Replacement Program
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SFPUC Water System Overview

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End of Useful LifeLACK OF REDUNDANCY

3 MAJOR EARTHQUAKE FAULTS

It’s Not “IF” But “WHEN”
San Francisco 1906
7.9 M

Hayward 1868
6.8M

Loma Prieta 1989
6.9MWater System Improvement Program (WSIP)• Initiated in 2002
• 87 Projects• 2 dams• 3 tunnels• 3 treatment facilities• Pipelines, pump stations,reservoirs, tanks, etc.

• 7 Counties• $4.8 Billion, Bond-Funded• 2021 Completion9Why Set Level of Service Goals?
• Establish performance standard• Ensure / improve reliability of the system• Develop capital improvement program that is tied toperformance levels• Identify deficiencies and cost-effective solutions• Provide quantifiable basis for capital improvement
projects• Support stakeholder decision-making process

Levels of Service Development• Reliability Study Phase I – Defined system & identified
hazards (1995)• Reliability Study Phase II – Quantified hazards andevaluated system response (2000)• Reliability Study Phase III – Reliability and risk analysis(2003)• Performance Standards I & II – Developed alternative
performance levels and improvement needs (2004)• Water System Improvement Program – Levels of Serviceand Program Adoption (2005)
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Level of Service Goals
Seismic Reliability
Delivery Reliability
Water Quality
Water Supply

Seismic Reliability LOS

Reduce vulnerability to earthquakes• Design improvements to meet current seismicstandards.
• After a major San Andreas, Hayward, or Calaveras
earthquake:• Deliver “basic service” to 3 region service area (SF,East/South Bay, and Peninsula);• Basic service is Average Winter Month Usage (229mgd);• Delivery to at least 70 percent of the customer turnouts
in each region
13Seismic Reliability LOS• Restore facilities to meet average-day demand (upto 300 mgd) within 30 days after a major
earthquake.

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Before WSIP: San Andreas 7.9M EventReliability Study Phase III, November 200415

After WSIP: San Andreas EventProbabilities of Failure

Reliability Study Phase III, November 2004

16Key Projects

Tesla Treatment Facility• $114 Million• 315 mgd capacity• UV disinfection• Compliance with latest
EPA guidelines• Design-Build contractTesla UV Treatment Facility

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Tesla UV Treatment Facility

New Irvington Tunnel• $340 Million Water
Transmission Tunnel• 3.5-mile long, 13.5-ft dia.
• Convention mining
with roadheaders andcontrolled detonation• Redundancy• Challenging groundconditions• Gassy tunnel

Drill and Blast Excavation

CONVENTIONAL MINING METHODBDPL Reliability Upgrade• $347 Million (tunnel)• $251 Million (pipeline)• 5 mile tunnel under SFBay• 19 mile pipeline in East
Bay & Peninsula• Hayward Fault crossing

Bay Bay Tunnel

TBM at Launch Shaft

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Hayward Fault Crossing

DESIGN CONCEPT AT TRACE B

DESIGN CONCEPT ANIMATION

Typical Section At Fault Zone

Test Bed at Cornell University

45 degrees

Secant pile wall
Precast U Shaped

South box fixed to lab
structure and modular
reaction wall

North box pulled by 4
actuators to create
strike-slip offset of 198
mm (Design offset = 6.5ft)

Ball Joint

Ball Joint and Slip Joint Construction

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Calaveras Dam Replacement• $823 Million• New seismically safedam• Restore original
storage level (31Billion gallon)• Difficult geologicalconditions• Environmental
challenges

8/25 aerial

Water
Treatment
SystemDisposal Sites

Left Abutment

Intake Tower

Spillway

New DamBorrowArea

Old DamStilling Basin

Right Abutment

Dam and Spillway Excavation
Left abutment

Axis of new dam

Spillway

Right abutment

Outlet pipe bench

Stilling basin

Cross Section of Replacement Dam

S - Upstream• Zoned Earth and Rock-Filled Dam• 220 feet high & 1200 feet in length• 80’ Crest and 1,180’ BaseN - Downstream

Construction Time Lapse VideoCalaveras Dam 201938

HTWTP Long-Term Improvements• $359 Million• 140 mgd capacity• Seismic retrofit• Process improvements• New seismic risks• Plant challenges
San Andreas Fault
Raw water quality
Site limitations
Maintain Operations

Project Components

Eastern Fault

Western Fault

New Filters41

11 MG Treated Water Reservoir

TWR Contactor and Storage Cell

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TWR Roof Construction

44Completed Site45

SF Water System Overview• 5 regionaltransmissionmains• 1,240 miles ofdistributionpipeline• 17 storage tanksand reservoirs• 10 pumpstations• 24 pressurezones
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SF Water Distribution System• 1,240 miles of pipelineo Cast irono Ductile irono Steel• 220 miles over 100 yrs• Average age of pipes:
57yrs

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WSIP Local Projects• 27 Seismic Upgrade Projects• Reservoirs, Pump Stations and Tanks• Large transmission pipelines and valves

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SF Potable Water Seismic LOS• WSIP LOS provides post-earthquake water to 4
out of 5 locations in San Francisco• Expand LOS for SF post-earthquake reliability• SF Seismic Reliability LOS being developed• “Critical Network” to be determined• Earthquake Resistant Ductile Iron Pipe (ERDIP)

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SF Potable Water Seismic LOS• Storage: 2 days average day demand + 2 hours of fire
suppression each pressure zone
• Water Supply Restoration• 24 hours - limited services to Critical Care Facilities• 72 hours - limited secondary distribution systempressurized• 7 days - limited transmission and distribution mains
restored to potable service.
• 90 days - secondary distribution system restored topotable service.

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Pipeline Replacement Program• Reliability Analysis (2011)• Total Risk Scores for all pipes• 320 miles identified for priority
replacement• Replacement goal:
miles/year

15• $55M Annual Budget51

320 Miles of Priority Pipeline

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Seismic Backbone System

Summary• LOS need to be matched to customer/stakeholder
expectations, funding/resources, & delivery schedules.
• Consistent LOS help control project scopes and budgets,and assist in recovery planning.
• Resources/facilities needed to achieve and maintain LOS
should be carefully predicted through iterative planningand modeling, and extensive stakeholder involvement.

54Questions?
Contact Information:
Sam Young, P.E.
swyoung@sfwater.org

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