to system reliability and sustainability
by improving local water supply and
availability during normal years, dry years,
and in emergencies. LADWP is focusing on
a combination of two ongoing initiatives:
the Local Water Supply Program and the
San Fernando Groundwater Basin (SFB)
Cleanup and Remediation Program (See
SOURCE Spring 2015). Its 2015 Urban
Water Management Plan (UWMP)
incorporates goals set as part of the mayor’s
Sustainable City Plan for developing local
water supplies through groundwater
remediation, stormwater capture, water
conservation, and water recycling. All
these initiatives are being developed
simultaneously and are generally of equal
importance to achieve the goal of 50
percent reduction in purchase of imported
supplies by 2025 and sourcing locally 50
percent of all water used in the city by 2035.
By 2040, the percentages of local water
supplies projected in the 2015 UWMP
are as follows: groundwater: 24 percent
(including increased pumping from aquifer
recharge with stormwater and recycled
water, up from the 2011-2015 average of
12 percent; new conservation: 16 percent
including stormwater reuse; and recycled
water: seven percent, up from the 2011-2015
average of two percent. The 2015 UWMP
also addresses cleanup and remediation of
contamination in the San Fernando Basin
(SFB) to ensure extracted water meets safe
drinking water standards. A healthy SFB
also sets a foundation for implementing
conjunctive use, recycled water and
stormwater capture projects that would
utilize the basin for storage.
Develop a Seismic Resilient
Pipeline Network
The objective of developing a seismic
resilient pipe network is twofold: to assure
that the system will be able to accommodate
damage and continue to provide water in
support of community recovery and/or to
limit outage duration. Developing a seismic-resilient
pipe network entails replacing
the entirety of the 7,000 miles of Water
System piping with either earthquake-resistant
pipes or other new pipes. Because
Water System piping is mostly built-out,
improvements to create a seismic resilient
pipe network will primarily consist of
strategic replacement of existing pipes
with earthquake-resistant pipe in regions
with the greatest risk while simultaneously
replacing deteriorating infrastructure to
improve overall water system resilience.
This is considered a cost-effective way to
address long-term seismic vulnerabilities
and maintain safe and reliable water
supplies on a daily basis for such a large
system. Because the earthquake-resistant
pipe is proposed to be placed as part of
the normal and ongoing pipe replacement
program, it is estimated that the effort will
take 120 years to complete based on the
planned pipe replacement rate of 300,000
feet per year. Earthquake hazards are being
incorporated into the pipe replacement
prioritization scheme with the goal of
reducing completion time. The cost for
implementation is incremental to normal
pipe replacement and depends on actual
seismic pipe costs, which are expected
to decrease in the future as the market is
developed.
Earthquake-resistant pipes may in-clude
ductile iron pipe, HDPE, specially
designed welded steel pipe, and polyvi-nylchloride
(PVC) among others that pro-vided
sufficient robustness against design
level ground deformations. (“Robustness”
meaning that the component is sufficiently
strong to resist the expected seismic forces
without serious damage. This differs from
overall system resilience, which means
the system can take a blow from a serious
earthquake, handle severe service losses,
and bounce back in a timely manner.)
As it relates to the fire protection
service, which is critical after a seismic
event, the proposed resilient network
will be developed by placing earthquake-resistant
pipe in a grid to form an arterial
subnetwork at intervals consistent with
capabilities of firefighting equipment to
relay water as well as system performance
criteria. From the arterial subnetwork,
earthquake-resistant pipes can be placed to
critical facilities such as hospitals, schools,
and emergency evacuation centers. This
network will also serve to reduce restoration
times for other less critical customers.
Improve Firefighting Water Supply
LADWP, Los Angeles Fire Department
(LAFD), the Mayor’s Office Emergency
Management Department, and other key
stakeholders are working collaboratively to
reduce risks of fire following an earthquake.
A key aspect is risk assessment, which will
be undertaken as three separate tasks: an
assessment of fire hazards, a fire vulnerabil-ity
study focusing on earthquake effects on
water system hydraulics and the ability to
meet fire protection services, and fire con-sequence
studies. In addition, a program is
being implemented to identify alternative
water supplies citywide that can be used to
fight fires. These include LADWP storage
facilities, swimming pools, rivers, creeks,
lakes, ponds, and temporary storage facil-ities
(e.g., stormwater detention basins).
Alternatives for reducing fire risks are
classified as short-term (a matter of years)
and long-term (multiple years to decades
to complete). Review of short-term alter-natives
identified the need to investigate:
• Improved access to existing storage and
production facilities.
• Methods to preserve water supply at
storage facilities.
• Utilizing temporary storage facilities.
• Developing additional new storage
facilities in high-risk regions.
• Developing drafting connections to
rivers, creeks, lakes, and ponds.
• Procurement of additional water
tankers.
Long-term alternatives require the
LADWP to:
• Develop performance objectives for re-silience
improvements consistent with
About LADWP
• Founded 1902;
provides water/
power to 4 million
people.
• Water sales:
549,000 acre-feet a year.
• Water supply is 86 percent
imported: Los Angeles Aqueduct
(owned/operated by LADWP,
Colorado River Aqueduct
(Metropolitan Water District
of Southern California) and
California Aqueduct (State Water
Project). Other sources: local
groundwater, local recycled
water.
• 473-square-mile service
area; 681,000 water service
connections.
• 7,337 miles of distribution mains;
113 pressure zones.
• 119 tanks/reservoirs; 96 pump
stations; 325 regulator stations;
60,714 fire hydrants.
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