San Diego Water Pollution (SANDIEGO)
CASE NUMBER: 60
CASE MNEMONIC: SANDIEGO
CASE NAME: San Diego-Tijuana Water Problems
1. The Issue
Untreated Mexican sewage of mostly residential origin, flowing
at a rate of 13-15 million gallons per day, contaminates the
Tijuana River Valley and drains on the U.S. side of the border near
San Diego. While this has been a problem for nearly 60 years, it
has been recently growing much worse. A health quarantine was in
effect at Imperial Beach, California, for over 140 days during 1993
due to the sewage, which adversely impacted that city's tourism
industry. Average annual losses have cost the city an estimated
$100 million. An agreement was reached in 1990 between the United
States and Mexico to build a $200 million border facility by 1995
to handle sewage flowing from Tijuana into San Diego. The city of
San Diego originally planned to build its own treatment facility
alongside the international one, but later canceled these plans.
The federal commission in charge of construction of the
international plant then announced that completion of the plant
would be delayed until at least 1998, partly due to the city of San
Diego's change in construction plans and winter floods. The need
for funding could threaten or delay completion of the project.
The U.S.-Mexican border area in recent times has come under
heightened scrutiny for high levels of environmental degradation.
Among a wide variety of different water pollution and depletion
problems affecting the border region, water pollution in the San
Diego-Tijuana area represents a highly-visible and serious
challenge to environmental quality. The problem is not new.
Untreated Mexican sewage has contaminated the Tijuana River Valley
in San Diego for 60 years. However, most experts agree that the
pollution problem has grown worse (see TIJUANA case).
Water quality is deteriorating along the border largely due to
overdevelopment. In 1991, the Council on Scientific Affairs of the
American Medical Association described the border region as "a
virtual cesspool" of pollution and disease, noting that 46 million
liters (about 13-15 million gallons) of raw sewage flow each day
into the Tijuana River. Much of the sewage that enters the river
in Mexico and crosses the border, sometimes referred to as
"renegade" flows, and travels through aged, inadequate or non-
The raw sewage has created an environment where mosquito
breeding is rampant and the potential for the transmission of
vector-borne diseases is high. At the beach, swimmers are in
danger of contracting hepatitis, dysentery, and other diseases from
bathing in waters polluted by sewage. Swimmers most frequently
suffer from gastroenteritis -- an illness characterized by
vomiting, diarrhea, stomach aches, and fever.
Imperial Beach, California (next to San Diego), first issued
a quarantine for hazardous ocean water quality in 1959.
Quarantines have been reimposed intermittently ever since, mostly
due to sewage releases in Mexico. Since the early 1980s, the
Playas de Tijuana treatment plant, located one mile south of the
border, has discharged about one million gallons per day of raw
sewage into the ocean due to leakages and system failures.
Drainage from the Tijuana River appears to have contributed the
most towards unsanitary conditions at the beach. Health
quarantines were in effect at Imperial Beach, for 146 days from
January through August of 1993, dampening the city's summer tourism
and commerce activity.
Most local marine biologists emphasize that sewage
contamination of the coastal margins is not a long-term problem.
Nature will take care of most of the clean-up on its own. Strong
offshore currents carry away most effluent before it has a chance
to cause long-term damage, and sunlight helps to break down
whatever remains. However, over the short-term, raw sewage can
accelerate the deoxygenation of the water, depriving plants and
animals of a necessary component for their survival. The release
of sewage particles into the water, called organic loading, can
block sunlight and in the process prevent normal plant growth and
photosynthesis. Sediment that settles on the ocean floor can kill
off bottom-feeders like brittle stars, sea urchins, starfish, sea
worms, clams, and mollusks as well as an entire generation of kelp
The water pollution problem in the San Diego-Tijuana area does
not emanate exclusively from Mexico. The California Regional Water
Quality Control Board has accused the city of San Diego of under-
reporting sewage spills and dumping 20,000 tons of sewage solids
into the Pacific Ocean over the past five and a half years. The
water agency threatened the city with a $3.3 million fine for
violations of environmental standards for sewage disposal. If the
fine is levied against the city, it will not be the first time. In
March, 1991, U.S. District Court Judge Rudi Brewster imposed a $3
million fine, citing 3,701 spills between July 1983 and December
1990 that released 99 million gallons of raw sewage and contributed
to some 400 health quarantines of beaches and public waterways.
One of the worst sewage spills in the nation's history took
place at Point Loma in February, 1992, when an outfall pipe
ruptured. Bacteria counts soared to more than 1,000 times the
legal limit, prompting local officials to close beaches from the
border to the mouth of the San Diego River for about two months.
Current allegations of water pollution by the city of San
Diego center largely around the operations of the Point Loma sewage
treatment plant near the northern part of San Diego Bay. The plant
receives about 180 million gallons of sewage each day from San
Diego and 16 other areas (including Tijuana), which includes about
200 tons of solids. In order to comply with federal permits under
the Clean Water Act, the plant must remove 75 percent of the solids
it receives. About 13 tons per day are allowed to be disposed of
at sea, and the remaining processed solids (called sludge) must be
kept on land in landfills or as compost. According to a state
sanitary engineer, at certain times during 1992 and 1993, the
plant's efficiency dropped as low as 17 percent because from 20 to
250 tons of solids that had previously been removed were returned
into the city's sewer system at a sludge-drying facility on Fiesta
The greatest effort to tackle the San Diego-Tijuana area water
pollution came in the form of a joint agreement signed in mid-1990
to build a $200-million facility along the border to handle sewage
flowing from Tijuana into San Diego. The plant would cleanse waste
effluent from Mexico to U.S. standards and discharge it several
miles from the coastline via a huge outfall. A new sewage
treatment plant for the city of San Diego would be built on the
same site, and the two plants would share a 12-foot diameter pipe
to dispose of the treated waste water. The city has since canceled
plans to build its own plant. Originally, Mexico was expected
to contribute about $41 million to the project, the U.S. Government
about $100 million, and the state of California and city of San
Diego the remainder. The plant was expected to become operational
In April, 1993, the International Boundary and Water
Commission (IBWC) -- a U.S. federal agency that addresses water
pollution along the border and is overseeing construction of the
border plant -- announced that completion had been delayed until at
least 1998. A commission spokesman blamed winter floods and the
city of San Diego for the delay. Some officials have expressed
concern that the treatment plant as currently proposed is already
undersized. Juan Vargas, a San Diego City Councilman, believes
that by the time the 25-million-gallon-a-day treatment plant is
operational, the flow of Mexican sewage will exceed the plant's
Funding problems could endanger the project further as work
continues on it. Estimates for the total cost of the plant now are
around $235 million. Congress approved $58 million towards
construction, less than the $70 million proposed by President
Clinton. State and local budget shortfalls are having an effect on
current treatment activities. In 1990, San Diego began treating
overflow Mexican sewage on a temporary basis, with the IBWC and the
California state government helping to pay for treatment costs.
Those funds have since dried up, forcing the city to curtail its
treatment of overflow. The city can handle 13 million gallons of
Mexican sewage daily. When rains or river flows exceed that
amount, the sewage is now allowed to flow through the Tijuana River
In September, 1993, the San Diego city and county governments
issued emergency declarations, hoping to spur the IBWC to spend up
to $10 million on temporary sewage treatment projects. Some short-
term measures that could be undertaken include: (1) construction of
an "equalization basin" in which Tijuana sewage would be stored
during the day and sent back to Tijuana at night when the system is
not as overburdened -- and (2) construction of 10 acres of
"oxidation" ponds capable of handling up to 30 million gallons a
day of raw sewage, which would be chlorinated and piped into
Mexican waters. The IBWC has opted for the latter plan.
A longer term solution to the U.S.-Mexican border water
pollution problems is needed. A border-bond plan as announced by
the Clinton Administration in July, 1993 could be a step in the
right direction. The border-bond plan would create a joint U.S.-
Mexican agency that would issue around $8 billion worth of bonds to
pay for the cleanup of the border. The bonds would be used to
build treatment plants for sewage and drinking water along border-
area rivers. Sewage and water fees from local residents on both
sides of the border would be used to repay the bonds.
In the overall picture, both the United States and Mexico have
demonstrated an increased willingness to peacefully negotiate to
overcome water pollution and depletion problems along their common
border. However, high levels of pollution have built-up over a
period of many years to contaminate water in the region. Even with
strong measures, it will take time for pollution levels to return
to acceptable levels.
3. Related Cases
(1): Domain = North America [NAMER]
(2): Bio-geography = DRY
(3): Environmental Problem = WATER
4. Draft Author: Steve Pearson
B. LEGAL Clusters
5. Discourse and Status: AGReement and INPROGress
The treaty to jointly build and operate an international
treatment facility was signed in 1990. As the facility has not yet
been completed, and funding to complete it remains uncertain, the
case could be considered to be moving towards resolution. While
the treaty addresses the pollution problem, it does nothing
physically to stop the pollution, nor does it specify any legal
measures on pollution control in the interim. Even after the
treatment facility is completed, there remain serious questions
about how much pollution will be prevented from entering the
6. Forum and Scope: NAFTA and REGION
Although this was originally a bi-lateral agreement between
the United States and Mexico, it is no doubt covered in provisions,
or related to them, in the NAFTA agreement.
7. Decision Breadth: 3 (USA, MEXICO, CANADA)
8. Legal Standing: TREATY
C. GEOGRAPHIC Clusters
9. Geographic Locations
a. Geographic Domain : North America [NAMER]
b. Geographic Site : Western North America [WNAMER]
c. Geographic Impact : MEXico
10. Sub-National Factors: YES
Both San Diego County and the California Regional Water
Quality Control Board act to monitor and enforce sanitary water
standards in the San Diego area. Primary responsibility for sewage
treatment rests with the county. The state imposes fines on the
county for violations of the standards.
11. Type of Habitat: DRY
The greatest impact will be along the U.S.-Mexico border.
D. TRADE Clusters
12. Type of Measure: Regulatory Standards [REGSTD]
A $239 million facility to treat human and other types of
waste is supposed to be completed by 1995. Waste that includes
lead, cyanide and others, is dumped at the rate of 20 million tons
per year into the Tijuana River. The Mexican portion of cost is 16
percent, and is a response to NAFTA criticisms (see NAFTA case). However, the Pacific pocket
mouse is home to the site of the facility, listed in February 1994
as an endangered species by the U.S. Fish and Wildlife Service.
This may delay or change the site of the project. Others have
proposed an integrated pond system followed by secondary treatment
through constructive wetlands.
13. Direct vs. Indirect Impacts: INDirect
14. Relation of Measure to Environmental Impact
a. Directly Related : NO
b. Indirectly Related : NO TOURism
c. Not Related : NO
d. Process Related : YES Pollution Sea [POLS]
15. Trade Product Identification: TOURism
16. Economic Data
Local officials estimate that pollution of the Tijuana River
has forced about 2.5 miles of shoreline to remain quarantined on a
near-permanent basis. Quarantines have cost Imperial Beach more
than $100 million a year in lost tourism and recreation
17. Impact of Measure on Trade Competitiveness: NA
18. Industry Sector: TOURism
19. Exporter and Importer: MANY and USA
The San Diego area receives millions of tourists each year,
from the United Sates and many foreign countries.
E. ENVIRONMENT Clusters
20. Environmental Problem Type: Pollution Sea [POLS]
Disease is a serious problem in this case. Diseases such as
malaria, dysentery, and hepatitis tend to flourish where large
quantities of raw sewage inundate the local surroundings. No
significant impact has been observed on the fishing or marine
harvesting industries, although the president of the urchin
producers association of San Diego has expressed deep concern about
high levels of sewage -- equating its potential damaging effects on
sea floor marine life with the effects of radiation.
21. Name, Type, and Diversity of Species
22. Resource Impact and Effect: HIGH and REGULatory
Economic growth has already elevated this problem, NAFTA may
only add to it.
23. Urgency and Lifetime: LONG and 100s of years
24. Substitutes: Bio-degradable [BIODG] products
VI. OTHER Factors
25. Culture: NO
26. Trans-Border: YES
The problem is caused because the Tijuana River flows across
the U.S.-Mexico border (see COLORADO case).
27. Human Rights: YES
Serious abuses of the environment have resulted in a variety
of diseases and deformities in the Mexican border area.
28. Relevant Literature
Balint, Kathryn. "$58 Million Agreed On For Sewage Plant Near
Border." San Diego Union-Tribune (October 2, 1993): B1.
Balint, Kathryn. "Opening of Sewage Facilities Postponed:
Golding Hits Lag on Plant to Treat Tijuana Wastes." San
Diego Union-Tribune (April 28, 1993): B1+.
Bradsher, Keith. "Trade Pact May Hinge on Border-Bond Plan."
New York Times (July 29, 1993): D1+.
Bramham, Daphne. "Lack of Enforcement Called Root of Problem on
Workers' Safety." The Vancouver Sun (October 19, 1993): A4.
Diringer, Elliot. "Water Sales' Flip Side -- Local Economic
Fallout." San Francisco Chronicle (June 7, 1993): A5.
Glionna, John M. "Spill Stirs Concerns Over the Health of
Coastal Sea; Marine Life: Most Oceanographers Believe
There is Little to Fear in the Long Run, But Admit Short-
Term Dangers." Los Angeles Times (San Diego Edition,
February 12, 1992): B1.
Kelly, Mary E., Dick Kamp and Michael Gregory. "U.S.-Mexico Free
Trade Negotiation and the Environment: Exploring the
Issues." Columbia Journal of World Business 26 (Summer
LaRue, Steve. "State Eyes Sewage Fines for San Diego: City
Accused of Excess Dumping, False Reports." San Diego
Union-Tribune (September 10, 1993): B1.
LaRue, Steve and Philip J. LaVelle. "Sewage Emergency Declared
in South Bay." San Diego Union-Tribune (September 8,
McDonnell, Patrick. "U.S., Mexico Sign Pact on Sewage Plant."
Los Angeles Times (July 3, 1990): A25.
National Research Council. Monitoring Southern California's
Coastal Waters. Washington, DC: National Academy Press,
Satchell, Michael. "Poisoning the Border." U.S. News & World
Report 110/17 (May 6, 1991): 32.
Staff Report. "U.S.-Mexico Plant Pushed in New Pact." Engineering
News Record 224 (June 21, 1990): 21-2.
Stammer, Larry B. and Granberry, Michael. "S.D., L.A. Counties
Top Fouled-Beaches Listing; Pollution: Sewage Spills Were
Top Cause. Big San Diego Spills This Year Will Make Next
Listing Even Worse." Los Angeles Times (San Diego County
edition, July 24, 1992): A1.
Szekely, Alberto. "Emerging Boundary Environmental Challenges
and Institutional Issues: Mexico and the United States."
Natural Resources Journal 33/1 (Winter 1993): 33-46.
"Tijuana River Cleanup on Track, Hill Told," Washington Post
(Thursday April 14, 1994), p. A3.
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