TEN-YEAR CAPITAL IMPROVEMENT PROGRAM - LA Differentiated

WATER SYSTEM OVERVIEW
LADWP delivers water to its customers
through a complex and expansive
network of large and small pipes, with
varied functions, measuring more than
7,200 miles in length. Trunk lines are
pipes with a diameter greater than
20 inches that transport water from
wells and aqueducts to reservoirs and
enable the movement of water from
one area of the city to another. Trunk
lines connect to smaller pipes known
as distribution mains that supply water
to the customer’s service connection.
Water meters at the connection site
then measure the customer’s water
usage. LADWP’s water distribution
system is so extensive, that if all the
pipes from trunk lines and distribution
mains were laid end to end in a straight
line, they would stretch from Los
Angeles to New York and back again.
Thirty years ago, 75% of L.A.’s water
supply began as snowmelt on the
slopes of the Eastern Sierra Nevada
Mountains. An additional 15% of water
came from local groundwater supplies
and approximately 10% was purchased
from Metropolitan Water District (MWD).
However, today the city’s traditional
water sources continue to change.
As a result of several significant
environmental restoration projects in
the Owens Valley, LADWP has reduced
the amount of water delivered from the
Eastern Sierra Nevada Mountains via
the Los Angeles Aqueduct from 75%
to approximately 35%. These projects
include restoring Mono Lake, controlling
dust pollution at Owens Dry Lake, and
re-watering the Lower Owens River.
In addition to a shrinking supply from
the Eastern Sierra, L.A.’s growing water
demand, and extended periods of
drought have led LADWP to augment
its water supply by increasing its water
purchases from MWD. Over the last
several years, LADWP has seen its
annual average purchase of water from
MWD increase from 15% to 53%, and its
groundwater supply decrease from 15%
to 11%. In an effort to supplement these
sources, Los Angeles is increasing its use
of recycled water – currently representing
about 1% of the total water supply. The
Water System is also moving aggressively
to meet the city’s growing demand
for water through increased water
conservation, watershed management,
groundwater banking, stormwater
capture and water transfers.
TEN-YEAR CAPITAL IMPROVEMENT PROGRAM
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