OUR MISSION: To provide our customers with high-quality, efficient and reliable water, power and sewer services in a manner that values environmental and community interests and sustains the resources entrusted to our care.
CITY DISTRIBUTION DIVISION
1990 Newcomb Avenue
San Francisco, CA 94124
T 415.550.4900
DATE: December 4, 2023
TO: Commissioner Tim Paulson, President
Commissioner Anthony Rivera, Vice President
Commissioner Sophie Maxwell
Commissioner Newsha K. Ajami
Commissioner Kate H. Stacy
THROUGH: Dennis Herrera, General Manager
Steven R. Ritchie, Assistant General Manager, Water
FROM: Bill Teahan, City Distribution Division Manager
Angela Cheung, Water Supply and Treatment Division Manager Andrew DeGraca, Water Quality Division Manager
SUBJECT: Water Pipeline Assessment: January 1, 2023 through June 30, 2023
Purpose
This memorandum covers maintenance and construction activities that the City Distribution Division (CDD), Water Supply and Treatment Division (WSTD), and Water Quality Division (WQD) performed to the linear assets between January 1, 2023, through June 30, 2023. This report includes four sections below:
1 The Lead User Service Line Program
• Contract WD -2889, “As -Needed Water Service Line Replacement Project” started construction on June 27, 2023.
2 Local Pipeline Renewal and Replacement Program
• 5.6 miles of L ocal Water System distribution and transmission pipelines were installed and placed into service.
• A 20-inch EFWS pipeline along 19 th Avenue from Irving to Kirkham and a 36- inch welded steel pipe are being constructed under the Public Works Department Contract 2652J. 3 Regional Pipeline Renewal and Replacement Program
• The construction contract for slip lining Bay Division Pipelines 3 and 4 under new Union Pacific Railroad tracks in Santa Clara was awarded.
4 Pipeline Inspection Program
• Approximately 9.2 miles of large diameter pipelines in t he Regional Water System were inspected during this reporting period.
5 Local Pipeline Failures
• There were 92 natural main breaks in the Local Water System during this reporting period, 87 were on older cast iron pipes . The total main break repair cost for the Local Water System was $1,710,700.
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1 Lead User Service Line Program
The SFPUC has identified approximately 1,400 public utility owned water ser vices needing replacement. WQD has employed a Water Enterprise Professional Services Contract to assist with identifying the material for the approximately 176,000 customer owned water services. To date, 404 SFPUC-owned galvanized service lines have been replaced and 66 (16.3%) were c onnected to lead whips. 171 (42.3%) replaced services were in disadvantaged neighborhoods. Chart 1 identifies the 404 replaced galvanized service lines based upon the year the service was originally installed and the presence of a lead whip. Map 1 identifies 404 g alvanized service lines that were replaced with a copper service.
Chart 1
Galvanized Service Lines Replaced
Map 1
Galvanized Service Lines Replaced within San Francisco
1 19 16 15
1 11 2 11 9
25 23
82 127
33 36
2 0
50 100
150
1900 1910 1920 1930 1940 1950 1960 1970 1980
Lead Whip No Lead Whip
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2 Local Pipeline Renewal and Replacement Program
Potable Pipelines
At the beginning of FY23 (Q1), the annual mileage for distribution system pipeline replacement was projected to be 8.2 miles. By FY23 Q4, 9 miles have been installed, a 10% increase over the projected miles. During this reporting period, 5.6 miles have been installed and placed in service, a 65% increase when compared to the last reporting period of 3.4 miles. The cost per mile for streetscape, transit, or ERDIP-type projects is approximately $8.6 million, an increase of approximately $0.6 million from the prior fiscal year. Table 1 identifies the number of miles completed during this period.
Table 1
Water Main Replacement Program FY 23 (Q3 and Q4)
Project Contract No. Miles
8-inch Ductile Iron Pipe & 24-Inch Earthquake Resistant Ductile Iron Pipe Water Main Installation on Prospect, Fair and Coso Avenues & Coleridge Street
WD-2718 0.91
16, 12, And 8-Inch Ductile Iron Water Main Replacement on Diamond St (27th St To Diamond Heights Blvd), 28th And
Duncan St (Douglass To Noe Sts.), Valley St (Diamond to Noe Sts.), And Noe St (Duncan to Valley Sts.)
WD-2843 1.55
16-Inch & 36-Inch, and 8-Inch Ductile Iron Water Mains at Various Locations on 19th Ave from Holloway Ave to Lincoln Way
WD-2775 0.30
36-inch Steel and 8-inch Ductile Iron Pipe Water Main
Installation on Vicente St. (19th to 25th Ave.)
WD-2806
0.49 L-Taraval Improvement Project (Sunset Blvd. to West Portal) WD-2859R 2.35 Total 5.6 miles
Emergency Firefighting Water System (EFWS) Pipelines
The EFWS is used to suppress multiple alarm fires as well as the protection of property from fire following an earthquake. Notable EFWS work includes:
• The EFWS pipeline from Lake Merced Pump Station to the Sloat Blvd /19th Avenue intersection and from 23rd/Vicente Street intersection to Lawton Street is under design. • New fireboat manifolds are in the planning stages for Fort Mason, Pier 35.5, Terry Francois Blvd, and Treasure Island at Ferry Landing.
• A new 20-inch EFWS pipeline (19th Avenue from Irving Street to Kirkham Street), and a new 36- inch diameter welded steel Potable Emergency Firefighting Water System (PEFWS) pipeline (19th Avenue from Vicente Street to Sloat Boulevard) are under construction as a part of the Public Works Department ’s 19th Avenue Roadway Improvements, Contract 2652J. Construction is expected to be completed July 2023.
• A new EFWS water supply and pipeline near the crest of Clarendon Avenue at Dellbrook Avenue is under construction.
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3 Regional Pipeline Renewal and Replacement Program
Capital improvement projects for the regional water pipelines progressed steadily during this reporting period. Planning and design continued for several pipeline projects that will replace and rehabilitate deteriorated pipe line segments. Table 2 identifies the regional water facility projects in the planning, design, and construction phases.
Table 2
Regional Pipeline Replacement Projects under Planning, Design, and Construction Title Limits Description Phase Milestone
Crystal Springs
Pipeline 2 (CSPL
2)
Reaches 2 and
3 Realign pipe, replace lining,
install new access manholes
Planning CER
completed
Bay Division
Pipeline 4 (BDPL
4)
Valve D50 to
D70
Replace pipeline Planning CER in
progress
Bay Division
Pipeline 1, 2, 3,
and 4
East Bay, South
Bay, Peninsula
Remove corrosion, replace
pipe lining, install new
isolation valves
Planning CER
completed
Crystal Springs
Pipeline 2 (CSPL
2)
Reach 5;
Valves K40 to
K50
Replace coal tar lining,
install new access
manholes, install new
isolation valves
Design 35% design
in progress
Town of Sunol Arroyo de la
Laguna Creek
Crossing
Replace pipeline at creek
crossing
Design 95%
complete
Town of Sunol I-680 Crossing Relocate raw and potable
water lines for freeway
widening
Construction 80%
complete
Bay Division
Pipeline 3 & 4
(BDPL 3 & 4)
Union Pacific
Railroad
Company
(UPRR)
Crossing
Slipline the pipelines under
railroad crossing
Construction 50%
complete
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4 Local and Regional Pipeline Inspection Programs
Local Water Facilities
AT&T has discontinued its 3G services and the service stoppage has affected the 160 monitoring sensors installed within the Diamond Heights neighborhood. Therefore, CDD is analyzing the feasibility of upgrading the 160 monitors to 4G.
The 150 monitoring sensors installed in the Portola and Bernal Heights neighborhood utilizes 4G services; therefore, a sensor upgrade will not be needed. No new potential points of interest have been discovered this reporting period. This signifies that there are minimal, if any, non-surfacing leaks within the Portola and Bernal Height neighborhoods. Consequently, SFPUC is investigating the feasibility of moving the sensors to another neighborhood that may benefit from the monitoring program, such as the Bayview, Visitation Valley, Portola, and the Excelsior neighborhood.
Regional Water Facilities
A total of 4 regional water facilities were inspected between January and June 2023, equating to 9.2 miles of transmission pipeline. Majority of the inspections were completed from inside the pipe, using the visual and sounding method. For Prestressed Concrete Cylinder Pipe (PCCP), Electromagnetic Technology (EM) and visual and sounding methods were used to identify broken prestressed wires and to detect delamination of th e inner concrete liner. Additionally, a new technology from Syrinix Pipeminder-T was installed to continuously monitor leaks and transient pressure for BDPL4.
Deficiencies found were minor and will either be repaired or be monitored in future inspections. Table 3 identifies the inspections that were conducted, summarizes the findings, and lists follow-up actions.
Table 3
Regional Water Facilities Inspections
Location
Inspection
Length Assessment Inspection Findings Follow-Up Actions Tesla
Manifold
Pipeline
Inlet and
outlet
Pipes
(0.15 mi)
Internal pipe
lining
Defects on lining
system; minor
blistering; cracks
found on CO2
injection pipe
− Defects were minor;
monitor in future
inspections; replacement
not necessary at this time
− Cracks on CO2 injection
pipe were repaired; monitor
in future inspections
Bay
Division
Pipeline 4
(BDPL4)
8.5 mi
segment
PCCP EM +
visual and
sounding
inspections,
internal pipe
lining
Mortar spalling at
joints; small opened
circumferential
cracks and joint
openings were
found; wire break
counts were low
− Exposed lining was
repaired
− Defects were minor and
pipe replacement was not
needed; monitor in future
inspections
Alameda
Siphon 2
(AS2)
0.5 mi
segment
Leak
investigation
and internal
inspection of
pipe lining
Failure at a pipe
joint, where the joint
had separated (most
likely caused by
creep from the
Calaveras Fault).
Multiple small lining
defects were found.
− The leak was repaired with
an internal steel band to
seal the joint
− Lining defects were covered
with sealant to prevent
further corrosion
Bay
Division
Pipeline 4
(BDPL4)
Valve D50
to D80
(1.25 mi
segment)
Installation of
Syrinix’s
Pipeminder-T to
continuously
monitor leaks
and transient
pressure
The Pipeminder-T
has consistently
detected small,
active leak and was
able to monitor
pressure remotely
− None at this time. Continue
monitoring
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5 Local Pipeline Failures
105 distribution main breaks occurred during this reporting period. Of this total, 92 (88%) were due to natural pipeline breaks out of which 87 (95%) occurred on cast iron pipes, 4 (4%) occurred on ductile iron pipe and 1 (1%) occurred on steel pipe.
The number of miles of pipe replaced varies year to year ; therefore, main break failures have been normalized to facilitate pipe break data comparisons. During this reporting period , pipelines installed in the 1880s experienced the highest main break rate with 21 breaks per 100 miles of pipeline and pipelines installed in the 1890s and 1920’s through 1950’s also experienced high break rates of 9 to 17 breaks per 100 miles of pipeline. Pipelines installed in other decades experienced 4 breaks or less per 100 mil es of pipe installed, which is more than an 80% decrease from the 1880’s. See C hart 2 identifying the number of breaks per 100 miles of pipe installation.
Chart 2
FY 22-23 Q3 & Q4 Normalized Pipeline Failures
21 9
3 11
17 12 11
4 2 3
0 5
10 15
20 25
1880 1890 1910 1920 1930 1940 1950 1960 1970 1980
No. Breaks per Mile of Pipe
Decade