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news
Orange County
beaches-more than meets the shore
Story and Photos
By Rochelle M. McCord
Special to the Online
Forty-Niner
If you've been
in Orange County lately, you've probably seen the sticker
that reads "Stop
the waiver."
The Orange
County Sanitation District's (OCSD) two treatment plants,
one in Fountain Valley, the other in Huntington Beach, empty
a combined 240,000,000 gallons of wastewater ("effluent")
every day into the ocean. How does this relate to the sticker?
Greg
Jewell , a member of the Surfrider
Foundation's Huntington Beach chapter, says the OCSD "refuses
to include full secondary treatment of all wastewater as a
method of long term bacteria reduction."
All of the wastewater
dumped by the OCSD does not undergo the highest level of treatment
before being dumped into the ocean, but because they're operating
under provision 301(h) of the
Clean Water Act, they continue to dump water that could
be cleaner, Jewell argued.
THE CLEAN WATER
ACT AND PROVISION 301(h)
- The Clean
Water Act is an amendment (1972) to the Federal Water
Pollution Control Act.
- The 1972 Clean
Water Act requires publicly-owned treatment plants to treat
wastewater with secondary treatment before emptying it into
the ocean.
- Provision 301(h)
was added to the Clean Water Act in 1977, allowing publicly-owned
treatment works who meet specific qualifications to empty
wastewater that has undergone both pre-treatment and primary
treatment, but not secondary treatment.
- According to
the OCSD, half of its wastewater undergoes secondary treatment.
HOW IS THE EFFLUENT
TREATED BEFORE IT REACHES THE OCEAN?
The OCSD
treats wastewater using a three-step method: preliminary
treatment, advanced primary treatment and secondary treatment.
1. Preliminary
Treatment
Wastewater is passed through a screen to remove non-organic
and large materials, then it is sent to grit chambers, where
the heaviest materials (coffee grounds, eggshells, etc.)
are removed and sent to a landfill.
2. Advanced Primary
Treatment (Removes 70% of wastewater solids)
Wastewater is pumped into large "settling basins,"
where chemicals are added to reduce hydrogen sulfide, odors,
and to aid in the consolidation of small solids into larger
solids.
Thickeners are
added to the wastewater to aid the heavier solids in sinking.
The solids are separated; heavy solids scraped off the bottom
and light solids skimmed off the top.
3. Secondary
Treatment (Removes 85% of wastewater solids)
This is the portion of treatment the waiver eliminates
under certain provisions, and only 50% of OCSD's wastewater
undergoes this treatment.
There are two
different processes of secondary treatment: filters and
sludge.Filters
"use revolving arms that spray wastewater over baseball
sized rocks covered in zoogleal slime (microorganisms) to
clarify the water," according to the descriptions on
the districts website.Sludge,
a brown mixture composed mostly of microorganisms, is mixed
with wastewater in large tanks where air and oxygen are
pumped in. The tank's environment encourages the reproduction
of the bacteria, which then eat most of the dissolved organic
material left in the wastewater.
WHERE DO THEY
DUMP IT?
OCSD discharges wastewater between four and five miles offshore,
from a pipe that rests 200 feet underwater.
The pipe
runs perpendicular to the shore, north of the Santa Ana River
in Huntington Beach.
- In summer 1999,
high levels of bacteria caused the closure of most of Huntington
Beach beaches.
- The closure
prompted a lengthy investigation by the OCSD and the city
of Huntington Beach, to determine the cause of the high
bacteria levels
STUDIES AND
PUBLICATIONS
Brett
Sanders, Associate Professor of Civil
and Environmental Engineering at University of California
Irvine with another UCI engineer, and a researcher from
the Scripps Institution
of Oceanography at UCSD completed an in depth study of
how cold water movement might transport sewage, like that
dumped in Huntington Beach, back ashore. The study was published
online in a scientific journal and will be available in print
on May 15th.
The OCSD released
an executive summary of the results of its 2001
Onshore Investigation.
FURTHER INTEREST
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