In 1986, a California city began polishing sewage through constructed marshes

50
Millio
Gallo s
of
Sewage
Flow
Daily
F om
Mexico
I to
Califo ia
Beaches

I
1986,
the
No the
Califo ia
city
of
A cata
completed
a
i ovative
wastewate
t eatme t
system
that
used
co st ucted
wetla ds
to
clea
sewage
while
also
c eati g
valuable
wildlife
habitat.
The
p oject
eve tually
became
pa t
of
the
A cata
Ma sh
a d
Wildlife
Sa ctua y,
a
307-ac e
atu al
a ea
that
combi es
wastewate
t eatme t,
habitat
esto atio ,
ec eatio
a d
e vi o me tal
educatio .
Today,
the
City
of
A cata
epo ts
that
mo e
tha
300
bi d
species
have
bee
eco ded
at
the
sa ctua y,
which
lies
alo g
the
Pacific
Flyway
a d
p ovides
a
impo ta t
stopove
fo
mig ato y
bi ds.

Dece t alized
wetla ds
eplace
a
costly
egio al
pla t

A cata’s
decisio
to
use
wetla ds
fo
wastewate
t eatme t
g ew
out
of
st ict
e vi o me tal
egulatio s
i t oduced
i
the
1970s.
At
the
time,
the
city’s
wastewate
system
discha ged
t eated
wastewate
i to
Humboldt
Bay.
Ea lie
imp oveme ts
to
the
pla t
had
i cluded
oxidatio
po ds
i
1958,
chlo i atio
facilities
i
1968
a d
dechlo i atio
facilities
i
1975.
Califo ia’s
Bays
a d
Estua ies
Policy
the
placed
tighte
limits
o
wastewate
discha ges
i to
bays
a d
estua ies.
The
policy
equi ed
commu ities
to
educe
such
discha ges
u less
they
could
show
that
the
discha ge
would
imp ove
the
eceivi g
wate s.

A
egio al
autho ity
espo ded
by
p oposi g
a
ce t alized
wastewate
t eatme t
pla t
fo
commu ities
a ou d
Humboldt
Bay.
Acco di g
to
EPA
eco ds,
the
p oposal
would
have
equi ed
la ge
pipeli es
a ou d
the
bay,
i cludi g
a
u de wate
pipeli e
be eath
a
active
avigatio
a ea.
The
system
would
also
have
equi ed
sig ifica t
e e gy
a d
ope ati g
esou ces
a d
would
have
discha ged
t eated
wastewate
offsho e
i
a
a ea
exposed
to
st o g
ocea
co ditio s.A cata
i stead
explo ed
a
smalle ,
dece t alized
app oach
usi g
co st ucted
wetla ds.
The
idea
was
i flue ced
by
ea lie
wastewate
aquacultu e
esea ch
i
the
a ea.
Begi i g
i
the
late
1960s,
esea che s
expe ime ted
with
usi g
pa tly
t eated
wastewate
a d
seawate
to
aise
you g
Pacific
salmo
a d
t out.
These
expe ime ts
suggested
that
wastewate
could
be
t eated
as
a
useful
esou ce
athe
tha
simply
as
waste.F om
1979
to
1982,
A cata
ca ied
out
pilot
studies
to
test
whethe
co st ucted
f eshwate
wetla ds
could
t eat
mu icipal
wastewate .
The
esults
showed
that
wetla ds
could
imp ove
wastewate
quality
while
also
suppo ti g
biological
p oductivity.
Based
o
the
successful
expe ime ts,
A cata’s
wastewate
task
fo ce
co cluded
that
a
wetla d-based
system
could
p ovide
eliable
t eatme t
while
offe i g
e vi o me tal
a d
ec eatio al
be efits.
State
app oval
followed
i
1983,
a d
the
full-scale
system
was
completed
i
1986.

How
the
wetla d
system
t eats
sewage

The
A cata
system
combi es
co ve tio al
wastewate
t eatme t
with
atu al
biological
p ocesses.
EPA
docume tatio
ide tifies
seve
mai
stages:
headwo ks,
p ima y
cla ificatio ,
solids
ha dli g,
oxidatio
po ds,
t eatme t
ma shes,
e ha ceme t
ma shes
a d
fi al
disi fectio .Fi st,
aw
sewage
e te s
the
headwo ks,
whe e
sc ee s
a d
g it
sepa ato s
emove
la ge
pieces
of
i o ga ic
mate ial.
The
wastewate
the
moves
i to
settli g
ta ks,
called
p ima y
cla ifie s,
whe e
suspe ded
solids
settle
to
the
bottom.
These
solids
a e
se t
to
digeste s
fo
fu the
t eatme t.
The
emai i g
liquid
flows
i to
oxidatio
po ds,
whe e
it
stays
fo
a
exte ded
pe iod.
Natu al
biological
p ocesses
i
the
po ds
emove
about
50
pe ce t
of
the
emai i g
biochemical
oxyge
dema d
a d
suspe ded
solids.The
wate
the
e te s
app oximately
7.5
ac es
of
t eatme t
ma shes
pla ted
with
ative
ha dstem
bul ush
(Schoe oplectus
acutus).
Pla ts
a d
mic oo ga isms
i
the
ma sh
help
emove
additio al
o ga ic
matte
a d
suspe ded
solids.
Afte
i te mediate
disi fectio ,
the
wate
moves
th ough
31
ac es
of
e ha ceme t
ma shes:
Geo ge
Alle
Ma sh,
Robe t
Gea hea t
Ma sh
a d
Da
Hause
Ma sh.
Sluice
gates
a d
woode
wei s
co t ol
the
flow
th ough
these
ma shes
befo e
the
wate
eceives
fi al
disi fectio
a d
is
discha ged
i to
Humboldt
Bay.The
wetla d
pla ts
pe fo m
seve al
impo ta t
fu ctio s.
Thei
leaves
p ovide
shade,
helpi g
limit
excessive
algae
g owth
a d
keepi g
wate
tempe atu es
lowe .
Pla ts
a d
mic oo ga isms
also
help
emove
ut ie ts
a d
b eak
dow
o ga ic
mate ial.
Bacte ia
a d
fu gi
livi g
i
the
wetla d
sedime ts
co t ibute
to
the
b eakdow
of
complex
substa ces,
while
the
sedime ts
ca
hold
metals
a d
othe
mate ials,
educi g
thei
moveme t
th ough
the
system.

F om
damaged
i dust ial
la d
to
wildlife
habitat

The
p oject
also
cha ged
a
heavily
distu bed
wate f o t
i to
a
dive se
wetla d
ecosystem.
Befo e
esto atio ,
the
a ea
co tai ed
a
aba do ed
lumbe
mill
po d,
cha elized
sloughs,
pastu ela d
a d
a
closed
mu icipal
la dfill.
The
p oject
t a sfo med
these
distu bed
a eas
i to
a
co ected
la dscape
co tai i g
f eshwate
ma shes,
salt
ma shes,
b ackish
po ds,
tidal
sloughs,
mudflats
a d
g assy
upla ds.Seve al
pa ts
of
the
sa ctua y
we e
built
by
eusi g
p eviously
distu bed
la d.
Robe t
Gea hea t
Ma sh
was
developed
o
fo me
pastu ela d,
while
Geo ge
Alle
Ma sh
was
co st ucted
ove
a
aba do ed
timbe
log
sto age
deck.
Da
Hause
Ma sh
was
c eated
f om
a
g avel
bo ow
pit
used
du i g
la dfill
wo k.
F a k
Klopp
Lake
was
also
fo med
f om
a
bo ow
pit
a d
late
became
habitat
fo
ive
otte s
a d
divi g
bi ds.
The
closed
la dfill
was
eclaimed
as
Mou t
T ashmo e,
a
g assy
public
hill.The
wildlife
espo se
was
sig ifica t.
Ea ly
EPA
epo ts
eco ded
mo e
tha
200
bi d
species
usi g
the
esto ed
a ea.
Today,
the
City
of
A cata
epo ts
mo e
tha
300
bi d
species
at
the
sa ctua y,
maki g
the
ma sh
a
impo ta t
habitat
fo
sho ebi ds,
wate fowl,
apto s
a d
mig ato y
bi ds.It
is
also
impo ta t
to
disti guish
the
o igi al
t eatme t
p oject
f om
the
sa ctua y’s
p ese t
size.
The
City
of
A cata’s
histo ical
timeli e
shows
that
the
ma sh
a ea
expa ded
ove
time,
eachi g
154
ac es
i
1986
a d
eve tually
g owi g
to
its
cu e t
307
ac es
th ough
late
la d
acquisitio s
a d
esto atio
p ojects.

Rec eatio
a d
atio al
ecog itio

Public
access
was
pa t
of
the
p oject’s
lo g-te m
visio .
Today,
the
sa ctua y
i cludes
about
five
miles
of
walki g
a d
biki g
t ails
a d
a
I te p etive
Ce te
with
educatio al
exhibits
a d
i fo matio
about
the
ma sh’s
wildlife,
histo y
a d
wastewate
t eatme t
system.The
p oject
also
eceived
atio al
atte tio .
I
1987,
the
City
of
A cata
eceived
ecog itio
th ough
the
Fo d
Fou datio
fo
its
i ovative
local
gove me t
wo k.
EPA
eco ds
state
that
the
awa d
i cluded
$100,000,
which
helped
suppo t
developme t
of
the
A cata
Ma sh
I te p etive
Ce te .The
A cata
Ma sh
p oject
became
a
impo ta t
example
of
atu e-based
i f ast uctu e.
I stead
of
t eati g
wastewate
a d
e vi o me tal
esto atio
as
sepa ate
goals,
A cata
combi ed
them
i
o e
system.
The
esult
was
i f ast uctu e
that
met
wastewate
t eatme t
eeds
while
also
esto i g
damaged
la d,
c eati g
wildlife
habitat,
suppo ti g
educatio
a d
esea ch,
a d
p ovidi g
a
public
ec eatio al
space.
The
p oject
demo st ated
how
a
mu icipal
utility
could
become
pa t
of
a
la ge
u ba
ecosystem
athe
tha
simply
bei g
a
piece
of
i dust ial
i f ast uctu e.

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