1. 20 percent saltier than the ocean, according to The Bee.
Desalinated water is fluoridated and chlorinated in
preparation for delivery to the San Diego County Water
Authority, which has a 30-year Water Purchase Agreement
with the plant’s developer and owner, Poseidon Water. A
private company, Poseidon Water specializes in developing
reverse osmosis seawater desalination plants.
The Water Authority started exploring the potential for a
desalination plant in the early 1990s. “This pioneering
project is the result of more than 17 years of planning,
permitting and construction,” stated Poseidon Water Chief
Executive Officer Carlos Riva in a news release. “It required
teamwork between Poseidon Water, the Water Authority,
our contractors, NRG Energy, and the cities of Carlsbad,
Vista and San Marcos.”
Coating consultant Denis Amyot, NACE Level 1, of TPC
Consultants, Inc., recalled his early involvement with the
project more than 10 years ago.
“I was first involved back in 2005-2006 with coating
contractor Parada Painting,” Amyot observed. “In 2007, I
provided Parada Painting budget numbers on a variety of
coating systems that were eventually used on the project.
With its dedication in December, 2015, the $1 billion Claude
“Bud” Lewis Carlsbad Desalination Plant opened a spigot
to the Pacific Ocean, creating a new, drought-proof source
of drinking water for 3.1 million people in San Diego County,
California.
As the largest ocean desalination plant in the nation and
Western Hemisphere, the Carlsbad Plant is considered the
future of water desalination in the U.S. by its proponents.
Citing officials of the International Desalination Association,
the Los Angeles Times reported, “San Diego is the
epicenter of desalination and water reuse development in
the U.S.A., and the undisputed birthplace of commercial
reverse osmosis.”
According to an article in The San Diego Union-Tribune,
the plant represents the “mainstreaming” of seawater
desalination in California. “About 15 other desalination
projects have been proposed for the state’s coastline, from
the San Francisco Bay Area to Southern California,” the
Union-Tribune article observed.
Located adjacent to the NRG Energy’s Encina Power
Station in Carlsbad, the desalination plant uses the same
water intake system used to draw cooling water from the
ocean into the power plant. After the water is filtered for
sediments, it is pumped through plastic-coated reverse
osmosis membranes that remove more than 99 percent of
the salt and other minerals.
“To produce 50 million gallons per day of fresh water,
Carlsbad will draw in 100 million gallons of seawater,” The
Sacramento Bee noted. “The difference is returned to the
ocean as discharge water, but with its salinity doubled.”
By mixing the discharge water with cooling water from the
Encina power plant, the discharge water will be only about
PLANT TAPS PACIFIC OCEAN AS
SOURCE OF DRINKING WATER
TNEME-NEWS
QUARTER ONE 2016

2. It took six to seven years to determine the project’s
feasibility.”
Among Amyot’s recommendations were coating systems
for structural steel, miscellaneous ferrous metals, exterior
surfaces of valves and piping, exterior polyvinyl chloride
(PVC) and chlorinated polyvinyl chloride (CPVC) piping, and
cast-in-place concrete infrastructure.
“All of the project’s coating systems met San Diego
Air Pollution Control District limits for volatile organic
compounds (VOCs), which is 250 grams per liter or less,”
Amyot explained. “Coating systems for drinking water
environments also complied with NSF/ANSI Standard
61 requirements for materials that come in contact with
potable water.”
The selection of coatings for interior and exterior structural
steel, pipes and valves included Series V69 Hi-Build
Epoxoline II, an advanced generation polyamidoamine
epoxy, Series 1075 and 1095 Endura-Shield, an aliphatic
acrylic polyurethane coating.
Coatings for non-submerged, exterior PVC and CPVC piping
were Series 115 Uni-Bond DF, a hydrophobic acrylic and
Series 1029 Enduratone, a low-VOC, High Dispersion Pure
(HDP) acrylic polymer.
The plant’s concrete surfaces were patched and filled with
Series 218 MotarClad, an epoxy-modified cementitious
mortar, to eliminate voids and bugholes, prior to being
topcoated with high-performance epoxies or polyurethanes.
Epoxy coatings for the plant’s concrete channels included
Series 22 Epoxoline, a 100 percent solids
polyamine epoxy, and
Series V140
Pota-Pox Plus, a polyamidoamine epoxy. Concrete secondary
containment structures used Series 239SC ChemBloc, a
novolac polyamine epoxy, and Series 282 Tneme-Glaze. The
secondary containment system for fluorosilicic acid tanks
used multiple coats of 252SC ChemBloc, a novolac vinyl
ester mat-reinforced mortar system.
Series 406 Elasto-Shield, a fast-setting polyurethane lining,
was part of the coating system for concrete in drinking water
environments, while Series 290 CRU, an extremely hard
urethane coating, provided additional protection against
abrasion and impact for concrete secondary containment
areas.
“Holiday testing was performed on all the concrete tanks,”
Amyot added. “Coating specifications included 19 color
designations, ranging from grays and browns to safety
red, yellow and orange. When you look at this plant, it’s
impressive.”
Approximately 16,000 desalination plants exist worldwide
in 150 countries, according to the Global Water Intelligence
and IDA Worldwide Desalting Plant Inventory.
“In the next 10 years, you are probably going to have three
big plants built in Southern California and another plant or
two in Northern California,” suggested Tom Pankratz, editor
of the Water Desalination Report newsletter. “The trend is
toward more desal.They are the most reasonable insurance
policy against a long, protracted drought.”
Tnemec Company, Inc. 6800 Corporate Drive Kansas City, Missouri 64120-1372 1-800-TNEMEC1 Fax:1-816-483-3969 www.tnemec.com