More reading if interested.
The New River channel begins at a
volcanic lake, near
Cerro Prieto.
[1] Today this lake feeds the
Cerro Prieto Geothermal Power Station. The river flows north 15 miles (25 km) through Baja California and another 66 miles (100 km) through California into the Salton Sea, the largest
lake in California. Flow at the border is approximately 200
ft³/s (6
m³/s), and about three times this flow at the Salton Sea because of collected agricultural discharges.
The New River’s flow is composed of waste from agricultural and chemical runoff from the farm industry
irrigation in the U.S. (18.4%) and Mexico (51.2%),
sewage from
Mexicali (29%), and manufacturing plants operating in Mexico (1.4%). By the time the New River crosses the U.S./Mexico border near
Calexico, California, the channel contains a stew of about 100
contaminants:
volatile organic compounds,
heavy metals (including
selenium,
uranium,
arsenic and
mercury), and
pesticides (including
DDT) and
PCBs. The waterway also holds the
pathogens that cause
tuberculosis,
encephalitis,
polio,
cholera,
hepatitis and
typhoid; levels for many of these contaminants are in violation of
United States Environmental Protection Agency (EPA) and Cal/EPA standards by several hundredfold.
[3] Fecal
coliform bacteria are at levels of 100,000 to 16 million
colonies per milliliter at the border checkpoint (possibly more, as this is the measuring capacity threshold), far above the
U.S.-Mexico treaty limit of 240 colonies.
[4][5]
The combined effects of increasing, highly polluted inflow from the New River and agricultural runoff have resulted in elevated bacterial levels and large algal blooms in the Salton Sea. With the lack of an outlet, salinity has increased by approximately 1% per year. Due to high selenium levels, the public was strictly advised to limit fish consumption from the Salton Sea in 1986, after which any amount was likely a health risk. Increasing water temperature, salinity and bacterial levels led to massive
fish die-offs (1992, 1994, 1996, 1999, 2006, 2008), and created the ideal breeding grounds for
Botulismavian botulism,
cholera and
Newcastle disease, which also led to massive avian epizootics from 1992-2008. Currently, the Salton Sea has a salinity of 4.4% (4.4 parts per 100), making it saltier than ocean water (3.5% for Pacific), and many species of fish are no longer able to reproduce or survive in the Salton Sea. It is now believed the
tilapia may be the only fish species able to persist there for a limited time. Without restoration actions, the sea will likely increase in toxicity, and remain an
ecological trap for avian species.