When rabbis in Brooklyn spotted a tiny crustacean
swimming in New York City's tap water last spring, the
ensuing debate about whether it rendered the city's water
unkosher seemed like an amusing, but esoteric dispute in a
particularly exacting Jewish enclave.
But in the months since, the discovery has changed the
daily lives of tens of thousands of Orthodox Jews across the
city. Plumbers in Brooklyn, Manhattan and Queens have been
summoned to install water filters - some costing more than
$1,000 - and dozens of restaurants have posted signs in
their windows trumpeting that they filter their water. As a
result, an entirely new standard is being set for what
constitutes a kosher kitchen.
"I don't want people in the community to be uncomfortable
in my home," said Laurie Tobias Cohen, executive director of
the Lower East Side Conservancy, explaining why she put a
filter on the faucet of her Washington Heights apartment.
The issue has created the perfect conditions for a
Talmudic tempest, allowing rabbis here and in Israel to
render sometimes conflicting and paradoxical rulings on
whether New York City water is drinkable if it is not
filtered. As with the original Talmudic debates, the
distinctions rendered for various situations have been
super-fine, with clashing judgments on whether unfiltered
water can be used to cook, wash dishes, or brush teeth, and
whether filtering water on the Sabbath violates an obscure
The creature, a crustacean known as a copepod that comes
in several species, is found in water all over the world and
is perfectly harmless. But it is a distant cousin of the
dreaded shrimp and lobster, shellfish whose consumption
violates the biblical prohibition against eating water-borne
creatures that lack fins and scales.
The prohibition refers only to species that can be seen
with the unaided eye - not, say, an amoeba - and the
question of whether the copepod is indeed visible is central
to the dispute. Some are so small as to be invisible, while
others can grow to a millimeter and a half in length, large
enough to be seen in water as small white specks.
The tumult is confined largely to New York because it is
one of the few cities that is exempt from federal filtering
requirements. Boston and Seattle are also exempt, but they
have nothing like the city's numbers of Orthodox. In New
York City, there are 331,200 Orthodox Jews, a third of the
Jewish population, according to a 2002 study done for UJA-Federation
of New York.
The sure winners in this theological tizzy are plumbers
and water filter entrepreneurs.
"We've had a 500 percent increase in sales," said Houston
Tomasz, vice president of Sun Water Systems of Fort Worth,
Tex., which manufacturers the Aquasana filter, whose
full-house version can cost more than $1,500 installed. "Not
everyone was a kosher Jew. When you start talking about
visible bugs in water, Jews aren't the only people who
In Brooklyn, a landlord started a firm overnight that he
called Eshel Filters. In September just before the Sukkot
holidays, when many Jews invite neighbors over, the company
installed 30 filters a day ranging in cost from $99 to
$1,150. Its motto: "The bug stops here."
The controversy is indicative of deepening religious
conservatism in the American Orthodox world. William B.
Helmreich, a professor of sociology and Judaic studies at
the City University of New York Graduate Center, said that
"in a society where people feel via the Internet and
television their very values are under constant attack,
there's a need for people to reassert their level of
religiosity, and one way this is done is by discovering new
restrictions which give people the opportunity to
demonstrate their adherence to their faith."
For generations, the most pious Jews - even revered
rabbis like Joseph B. Soloveitchik and Moses Feinstein -
drank unfiltered New York water with no evident concern. But
six months ago, a group of Brooklyn rabbis were examining
some lettuce imported from Israel that was supposed to be
bug-free, but which appeared to have insects on its leaves.
After an investigation, they determined that the "bugs" had
arrived after the lettuce was washed in New York City water,
and said that in the right light they could see the telltale
specks with their own eyes.
At some point, a delegation of rabbis took a field trip
to the city's reservoirs and asked officials some detailed
questions about the origins of the water and the copepods.
(Of the three reservoir systems, only one - the Croton - is
in the process of introducing filtering, with a plant that
will cost an estimated $1 billion but will not be completed
The question lingered unresolved by a major communal
authority until the Orthodox Union, which certifies as
kosher 275,000 products in 68 countries, weighed in last
August after checking some water samples.
"When they saw the first sample they didn't feel it
reached the threshold of being visible," said Rabbi Menachem
Genack, the rabbinic administrator for the Orthodox Union.
"What changed people's minds is when they saw a sample taken
from a pond and saw them scooting around. Those are beyond
The Orthodox Union recommended that restaurants and
caterers under its supervision filter their water before
using it in drinking and cooking, a policy that quickly was
adopted by many homes as well. The policy considered
different practical possibilities. Dishes may be washed by
hand in unfiltered water, it said, if the dishes are towel
dried or left to drip-dry without puddles of water in them.
But it also said water should not be filtered on the
Sabbath because one of the 39 varieties of work forbidden by
the sages includes "selection," or sifting of food, like
separating wheat from the chaff or raisins from a noodle
The organization issued the policy to make sure even the
most stringent consumers would be satisfied that what they
were eating was kosher to the highest standards. But a
debate continues within its own rabbinical ranks about how
the filtering policy should be applied in ordinary homes,
and some rabbis have suggested the filtering frenzy may have
gone too far.
Rabbi Yisroel Belsky, one of the leaders of Torah Vodaath
rabbinical seminary in Brooklyn and an important voice on
Orthodox Union kosher matters, said in an interview that
there was no requirement to check for things that were
impossible to see in the years before microscopes.
"If everybody goes around thinking that whoever doesn't
filter water is actually eating things that are treyf," he
said, using a Hebrew word for unkosher, "there will probably
be all kinds of disputes between individuals and marriage
problems that can cause a cleavage."
Many Jews have been left confused. Fran B., a marketing
manager for a software firm who asked that her last name be
withheld, said she did not want to tear up the granite
countertops in her Manhattan apartment to install a filter
under the sink, so she lugged bottled water from the
"On the one hand, I'm drinking bottled water, but on the
other hand I'm eating at friends' houses who have never even
heard of this," she said.
Others are perplexed about whether to filter at all,
filter on Sabbath, or filter for purposes of cooking,
washing dishes or brushing teeth.
"The difference in opinions is driving a lot of people
crazy," said Rabbi Ephraim Buchwald, director of the
National Jewish Outreach Program in Manhattan, who hauls
bottled water to his apartment so he will not have to filter
on Sabbath. "You can't imagine what a turmoil it is."
In an article in The Jewish Press, David Berger, a
professor of history at the City University Graduate Center
and a rabbi, said, "The notion that God would have forbidden
something that no one could know about for thousands of
years, thus causing wholesale, unavoidable violation of the
Torah, offends our deepest instincts about the character of
both the Law and its Author."
Rabbi Moshe Dovid Tendler, who is a professor of biology
and of Talmudic law at Yeshiva University, said he spotted
the telltale specks only after first looking at copepods
through a 60-power dissecting microscope.
But having seen them, he said he thought they should be
filtered out. Nevertheless, he does not believe the filters
should be turned off on Sabbath - Jewish law already allows
people to pick algae or other vegetation out of water. And
he certainly does not worry about whether pious Jews who
drank unfiltered tap water in the past sinned.
"The hidden things belong to God," he said. "We are
responsible for what we see. If you don't know about it and
don't see it, then it doesn't exist. So those who drank the
water before were drinking kosher water."