<s>
EPANET	B-Language
(	O
Environmental	O
Protection	O
Agency	O
Network	O
Evaluation	O
Tool	O
)	O
is	O
a	O
public	O
domain	O
,	O
water	O
distribution	O
system	O
modeling	O
software	O
package	O
developed	O
by	O
the	O
United	O
States	O
Environmental	O
Protection	O
Agency	O
's	O
(	O
EPA	O
)	O
Water	O
Supply	O
and	O
Water	O
Resources	O
Division	O
.	O
</s>
<s>
EPANET	B-Language
first	O
appeared	O
in	O
1993	O
.	O
</s>
<s>
EPANET	B-Language
2	O
is	O
available	O
both	O
as	O
a	O
standalone	O
program	O
and	O
as	O
an	O
open-source	O
toolkit	O
(	O
Application	B-Application
Programming	I-Application
Interface	I-Application
in	O
C	B-Language
)	O
.	O
</s>
<s>
Its	O
computational	O
engine	O
is	O
used	O
by	O
many	O
software	O
companies	O
that	O
developed	O
more	O
powerful	O
,	O
proprietary	O
packages	O
,	O
often	O
GIS-centric	O
.	O
</s>
<s>
The	O
EPANET	B-Language
"	O
.inp	O
"	O
input	O
file	O
format	O
,	O
which	O
represents	O
network	O
topology	O
,	O
water	O
consumption	O
,	O
and	O
control	O
rules	O
,	O
is	O
supported	O
by	O
many	O
free	O
and	O
commercial	O
modeling	O
packages	O
.	O
</s>
<s>
EPANET	B-Language
provides	O
an	O
integrated	O
environment	O
for	O
editing	O
network	O
input	O
data	O
,	O
running	O
hydraulic	O
and	O
water	O
quality	O
simulations	O
,	O
and	O
viewing	O
the	O
results	O
in	O
a	O
variety	O
of	O
formats	O
.	O
</s>
<s>
EPANET	B-Language
provides	O
a	O
fully	O
equipped	O
and	O
extended	O
period	O
of	O
hydraulic	O
analysis	O
that	O
can	O
handle	O
systems	O
of	O
any	O
size	O
.	O
</s>
<s>
EPANET	B-Language
's	O
water	O
quality	O
modeling	O
functionality	O
allows	O
users	O
to	O
analyze	O
the	O
movement	O
of	O
a	O
reactive	O
or	O
non-reactive	O
tracer	O
material	O
which	O
spreads	O
through	O
the	O
network	O
over	O
time	O
.	O
</s>
<s>
The	O
visual	O
network	O
editor	O
of	O
EPANET	B-Language
simplifies	O
the	O
process	O
of	O
building	O
piping	O
network	O
models	O
and	O
editing	O
their	O
properties	O
.	O
</s>
<s>
These	O
various	O
types	O
of	O
data	B-General_Concept
reporting	I-General_Concept
visualization	O
tools	O
are	O
used	O
to	O
assist	O
to	O
analyze	O
the	O
networks	O
,	O
which	O
include	O
the	O
graphics	O
views	O
,	O
tabular	O
views	O
,	O
and	O
special	O
reports	O
.	O
</s>
<s>
EPANET	B-Language
hydraulics	O
engine	O
computes	O
headlosses	O
along	O
the	O
pipes	O
by	O
using	O
one	O
of	O
the	O
three	O
formulas	O
:	O
</s>
<s>
Within	O
EPANET	B-Language
,	O
pumps	O
are	O
modeled	O
using	O
a	O
head-flow	O
curve	O
,	O
which	O
defines	O
the	O
relationship	O
between	O
hydraulic	O
head	O
imparted	O
to	O
the	O
system	O
by	O
the	O
pump	O
and	O
flow	O
conveyed	O
by	O
the	O
pump	O
.	O
</s>
<s>
EPANET	B-Language
can	O
also	O
model	O
a	O
pump	O
as	O
a	O
constant	O
power	O
input	O
,	O
effectively	O
adding	O
a	O
given	O
amount	O
of	O
energy	O
to	O
the	O
system	O
downstream	O
of	O
the	O
pump	O
element	O
.	O
</s>
<s>
The	O
network	O
hydraulics	O
solver	O
employed	O
by	O
EPANET	B-Language
uses	O
the	O
"	O
Gradient	O
Method	O
"	O
first	O
proposed	O
by	O
Todini	O
and	O
Pilati	O
,	O
which	O
is	O
a	O
variant	O
of	O
Newton	O
–	O
Raphson	O
method	O
.	O
</s>
<s>
EPANET	B-Language
includes	O
the	O
capability	O
to	O
model	O
water	O
age	O
and	O
predict	O
flow	O
of	O
non-reactive	O
and	O
,	O
under	O
simplified	O
conditions	O
,	O
reactive	O
materials	O
.	O
</s>
<s>
While	O
the	O
internal	O
water	O
quality	O
simulation	O
capabilities	O
only	O
evaluates	O
decay	O
or	O
growth	O
of	O
a	O
single	O
constituent	O
,	O
an	O
extension	O
is	O
available	O
(	O
EPANET-MSX	O
)	O
,	O
which	O
allows	O
modeling	O
of	O
interactions	O
between	O
constituents	O
.	O
</s>
<s>
EPANET	B-Language
's	O
computational	O
engine	O
is	O
available	O
for	O
download	O
as	O
a	O
separate	O
dynamic	O
link	O
library	O
for	O
incorporation	O
into	O
other	O
applications	O
.	O
</s>
<s>
The	O
source	O
code	O
for	O
EPANET	B-Language
2	O
is	O
available	O
on	O
the	O
EPA	O
's	O
EPANET	B-Language
website	O
.	O
</s>
<s>
In	O
2012	O
the	O
EPANET	B-Language
toolkit	O
,	O
written	O
in	O
C	B-Language
,	O
was	O
rewritten	O
in	O
Java	O
in	O
a	O
more	O
object-oriented	B-Language
style	O
.	O
</s>
<s>
EPANET	B-Language
uses	O
a	O
binary	O
file	O
format	O
,	O
but	O
also	O
includes	O
the	O
capability	O
for	O
importing	O
and	O
exporting	O
data	O
in	O
dxf	O
,	O
metafile	O
,	O
and	O
ASCII	O
file	O
formats	O
.	O
</s>
<s>
EPANET	B-Language
's	O
ASCII	O
file	O
format	O
is	O
called	O
an	O
input	O
file	O
within	O
EPANET	B-Language
,	O
and	O
uses	O
a	O
file	O
extension	O
"	O
.inp	O
"	O
.	O
</s>
<s>
While	O
EPANET	B-Language
is	O
used	O
as	O
the	O
computational	O
engine	O
for	O
most	O
water	O
distribution	O
system	O
models	O
,	O
most	O
models	O
are	O
developed	O
and	O
maintained	O
in	O
hydraulic	O
modeling	O
packages	O
based	O
on	O
EPANET	B-Language
's	O
computational	O
engine	O
.	O
</s>
<s>
,	O
open	O
source	O
GIS	B-Application
software	I-Application
to	O
manage	O
water	O
pipes	O
and	O
consumers	O
,	O
developed	O
by	O
available	O
at	O
.	O
</s>
<s>
Most	O
of	O
these	O
applications	O
allow	O
for	O
multiple	O
demand	O
conditions	O
,	O
planning	O
scenarios	O
,	O
and	O
various	O
methods	O
of	O
integrating	O
with	O
other	O
data	O
sources	O
an	O
agency	O
may	O
already	O
have	O
in	O
place	O
not	O
supported	O
in	O
EPANET	B-Language
,	O
such	O
as	O
GIS	B-Application
,	O
and	O
support	O
additional	O
types	O
of	O
analyses	O
not	O
found	O
in	O
EPANET	B-Language
.	O
</s>
<s>
ESurvey	O
Water	O
is	O
developed	O
to	O
create	O
Auto	O
Designed	O
Longitudinal	O
Profiles	O
,	O
and	O
auto	O
generation	O
of	O
the	O
final	O
outputs	O
after	O
the	O
hydraulic	O
design	O
is	O
completed	O
in	O
EPANET	B-Language
and	O
other	O
software	O
.	O
</s>
