Bab 4 Randrain Silvia Fix 123
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Transcript of Bab 4 Randrain Silvia Fix 123
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BAB IV
DATA DAN ANALISA DATA
4.1. Perhitungan Curah Hujan
4.1.1. Koefisien Thiessen
Menghitung luas daerah pengaruh (luas poligon) untuk setiap stasiun hujan:
Luas Poligon =2
∑ ++ − n1n1nn .YX.YX
Tabe 4.1. Perhitungan Koefisien Thiessen
Stasiun
Luas !"#
$
%
Koefisien
ThiessenStasiun B 71,5625 ,277
Stasiun C 65, ,252
Stasiun D !5, ,"2#
Stasiun & "6,4125 ,141
'u#ah 257,#75 1,
Sumber : Hasil Perhitungan
4.1.$. Perhitungan Curah Hujan Harian (a"si#u# )engan (eto)e Poigon
Thiessen
$tasiun Perhitungan %urah hujan rerata &asing'&asing stasiun dilakukan
dengan jalan &elakukan perkalian antara koeisien hiessen dengan %urah hujan
pada &asing'&asing stasiun* +ari perkalian data %urah hujan tiap stasiun dengan
koeisien hiessen dapat ditentukan hujan rerata daerah* ilai %urah hujan rerata
daerah ter-esar terse-ut &erupakan %urah hujan &aksi&u& dengan &etode
hiessen untuk luasan daerah stasiun terse-ut* Menghitung %urah .ujan harian
&aksi&u& tahunan dengan &etode Poligon hiessen,
dengan: / = %urah hujan daerah (&&)
/ 1,/ 2,/ n = %urah hujan pada titik penga&atan (&&)
01,02,0" = luas total daerah penga&atan (k&2)
erdasarkan perhitungan Poligon Thiessen diperoleh:
Luas Pengaruh $tasiun : 71,5625 k&2
Luas Pengaruh $tasiun : 65, k&2
Luas Pengaruh $tasiun + : !5, k&2
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Luas Pengaruh $tasiun 3 : "6,4125 k&2
Luas otal : 257,#75 k&2
erdasarkan Poligon hiessen luas daerah diperoleh luas &asing'&asing
stasiun dan koeisien hiessen se-agai -erikut:
$tasiun () = 71,5625 257,#75 = *277
$tasiun () = 65, 257,#75 = ,252
$tasiun + (+) = !5, 257,#75 = ,"2#
$tasiun 3 (3) = "6,4125 257,#75 = ,141
Perhitungan %urah hujan rerata &asing'&asing stasiun dilakukan dengan
jalan &elakukan perkalian antara koeisien Thiessen dengan %urah hujan*
e&udian dari data %urah hujan rerata terse-ut, dipilih data %urah hujan ang
paling -esar (&aksi&u&)*
1* ontoh perhitungan %urah hujan tanggal 6 e-ruari 24
$tasiun = 24 &&
$tasiun = "1 &&
$tasiun + = 2! &&
$tasiun 3 = 24 &&
2 * urah hujan &asing'&asing stasiun
/u&us:
* + KT, . *,
dengan:
8 = koeisien Thiessen di stasiun 8
/8 = tinggi %urah hujan di stasiun 8 (&&)
Maka %urah hujan di:
$tasiun = 24 8 ,277 = 6,6576 &&
$tasiun = "1 8 ,252 = 7,!1! &&
$tasiun + = 2! 8 ,"2# = #,2257 &&
$tasiun 3 = 24 8 ,141 = ","!75 &&
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1* .ujan /erata +aerah
/u&us:
* + !KTB.* B% - !KTC.* C% - !KTD.* D% - !KT&.* &%
+ 6,6576 9 7,!1! 9 #,2257 9 ","!75
= 27,!17 &&
Perhitungan selanjutna dita-elkan pada ta-el 4*2*
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Tabe 4.$. Perhitungan Curah Hujan (a"si#u# (eto)e Poigon Thiessen
Tahun Tangga
Curah Hujan *erata
!##%Curah Hujan *erata !##%
'u#ah
H #a"s
STASIN B , KT
B
C , KT
C
D , KT
D
& , KT
&!##%
B C D &
24
6'e- 24 "1 2! 24 6,6576 7,!1! #,2257 ","!75 27,!17
42,1"7
2'0pr 64 "1 "4 "! 17,75"7 7,!1! 11,226 5,"6"6 42,1"7
16'un 44 5" 15 57 12,256 1","54 4,#42" !,454 "!,5474
26'o; 4# 55 "! 12 1",5#26 1",!57# 12,526 1,6#"! 41,664#
1'+e% 1" 64 47 24 ",662 16,1256 15,4!6 ","!75 "!,65"
25
2!'an 72 " 7 1# 1#,#72# 7,55!# 2",64" 2,6!1! 5",277!
6,21#4
11'Mar 51 62 65 64 14,1474 15,6217 21,416! #,""4 6,21#4
15'0pr "1 55 21 52 !,5##4 1",!57# 6,#1#" 7,""#7 "6,716"
22'ul "1 67 "1 26 !,5##4 16,!!15 1,2142 ",66#! "#,"64#
14'o; 4 1" 4 "5 11,#6 ",2755 1",17#6 4,#42 "2,4#1"
26
15'an "7 "5 17 56 1,26"! !,!1!7 5,61" 7,#4" "2,5!!1
4#,!17
4'Mar 1! "7 "1 52 4,##"2 #,"226 1,2142 7,""#7 "1,!6#7
1"'Ma 4# "1 "! 2" 1",5#26 7,!1! 12,526 ",2464 "7,175
6'0ug 25 "1 7" 41 6,#"5 7,!1! 24,527 5,7!7 44,5!56
26'+e% 64 2! 6# 16 17,75"7 7,54# 22,7"4! 2,25!4 4#,!17
27
!'e- "1 2! "1 7 !,5##4 7,54# 1,2142 #,!!" "5,74!#
55,1"4
"'0pr 5# "7 5! 7" 16,"667 #,"226 1#,114 1,""! 55,1"4
1!'un 2! 1! "1 4" 7,7672 4,5"5" 1,2142 6,6#" 2!,5!61
2#'o; 5" 1" 6! 26 14,722 ",2755 22,45" ",66#! 44,52#
1'+e% "5 25 "1 41 #,7# 6,2##1 1,2142 5,7!7 "2,#"
2! 12'e- "1 7 2 21 !,5##4 17,6"74 6,5!#! 2,#641 "5,7#7 45,11#6
!'Mar 4 "5 15 61 11,#6 !,!1!7 4,#42" !,61 "",4671
"'0pr "1 "6 "1 5 !,5##4 #,76 1,2142 7,574 "4,#416
6'$ep 41 47 "1 5" 11,"7"4 11,!422 1,2142 7,4!! 4,#17
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Tahun Tangga
Curah Hujan *erata
!##%Curah Hujan *erata !##%
'u#ah
H #a"s
STASIN B , KT
B
C , KT
C
D , KT
D
& , KT
&!##%
B C D &
12'
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Tahun Tangga
Curah Hujan *erata
!##%Curah Hujan *erata !##%
'u#ah
H #a"s
STASIN B , KT
B
C , KT
C
D , KT
D
& , KT
&!##%
B C D &
14'+e% 64 "1 "7 74 17,75"7 7,!1! 12,1#11 1,444# 4!,25
Sumber : Hasil Perhitungan
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4.1./. Perhitungan Curah Hujan *an0angan )engan (eto)e Log Pearson III
urah hujan &aksi&u& daerah tahunan (24'21")
Men%ari urah .ujan /an%angan dengan Metode Log Pearson
/u&us:
Sd k LogX LogXi *+=
dengan:
a* Pro-a-ilitas
>11 x
n
m P
+=
dengan:
& = no&or urut data 1,2,",?
n = ju&lah data
-* ilai rata'rata
n
LogXi
LogX
n
i
∑=
= 1
dengan:log @i = nilai %urah hujan (dala& Log)
n = ju&lah data
%* ilai de;iasi standar dari log @:
1
)(1
−
−
=
∑=
n
LogX LogXi
Sd
n
i
d* ilai koeisien kepen%engan:
"
1
"
)2)(1(
)((
Sd nn
LogX LogXin
Cs
n
i
−−
−
=
∑=
Menentukan urah hujan /an%angan dengan Metode Log Pearson III
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Tabe 4./. Perhitungan Hujan *an0angan )engan (engguna"an (eto)e Log Pearson III
No i Log i P !2% !Log i 3 Log % !Log i 3 Log %$ !Log i 3 Log %/
1 42,1"7 1,6246 ,## ',6#2! ,4! ',""
$ 42,"5!# 1,626# ,1!1! ',66#" ,44! ',"
/ 45,11#6 1,6544 ,2727 ',"#51 ,156 ',6
4 4!,25 1,6!"1 ,"6"6 ',1!2 ,12 , 4#,!17 1,6#72 ,4545 ,""7 ,1 ,
5 5,!272 1,761 ,5455 ,1222 ,15 ,
6 51,51!5 1,712 ,6"64 ,1!# ,"" ,1
7 51,717 1,71"6 ,727" ,1#7 ,"# ,1
8 55,1"4 1,7412 ,!1!2 ,47" ,224 ,11
19 6,21#4 1,77#7 ,##1 ,!5!6 ,7"7 ,6"
'u#ah 4#6,##6 16,#"!! 5, , ,2144 ,6
*ata3rata 4#,6##1 1,6#"# ,5 , ,214 ,1
S) 5,665 ,4!! ,2752 ,4!!1 ,256 ,26
Sumber : Hasil Perhitungan
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LogX = 1,6#"#
$d = ,4!!
s = *74
$ehingga persa&aanna adalah:
Log @ = s 9 (Log @ rerata 8 $d)
= ,74 9 (1,6#"# 8 ,4!!)
erdasarkan nilai s = ,74, &aka ditentukan nilai k setiap kala ulang ang
digunakan* $ehingga %urah hujan ran%angan dengan kala ulang ang akan digunakan
&enurut kala ulang adalah se-esar:
Tabe 4.4. Perhitungan Hujan *an0angan
Percen
t
Tr
!tahun%
rerataS) Cs
Peuang K
Hujan
ran0angan
!##%
!2% !tabe% Log
5 1,5 1,6#4 ,4# ,74 #5 31:5$ 1,615 41,17
25 1,"" 1,6#4 ,4# ,74 75 39:695 1,65# 45,647
5 2 1,6#4 ,4# ,74 5 39:91$ 1,6#" 4#,"52
75 4 1,6#4 ,4# ,74 25 9:585 1,72! 5",44
! 5 1,6#4 ,4# ,74 2 9:7/7 1,7"5 54,2#!# 1 1,6#4 ,4# ,74 1 1:$78 1,757 57,12
Sumber : Hasil Perhitungan
4.1.4. ji Kesesuaian Distribusi !S#irno;3Ko#ogoro; )an Chi S
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No !##% Log Sn!% K Pr P,!% Sn!%3P,!%
1 42,1"7 1,6246 ,## '1,41#" #2,7"7 ,7#" ,116
$ 42,"5!# 1,626# ,1!1! '1,"712 #1,"!!! ,!61 ,#57
/ 45,11#6 1,6544 ,2727 ',!#5 7!,7252 ,2127 ,6
4 4!,25 1,6!"1 ,"6"6 ',221! 57,5627 ,4244 ,67
4#,!17 1,6#72 ,4545 ,6# 47,14#" ,52!5 ,74
5 5,!272 1,761 ,5455 ,254 4,7471 ,5#25 ,471
6 51,51!5 1,712 ,6"64 ,"76 "6,5"" ,6"5 ,14
7 51,717 1,71"6 ,727" ,4"7 "5,"""5 ,6467 ,!6
8 55,1"4 1,7412 ,!1!2 ,#6#1 17,#27 ,!2#1 ,1#
19 6,21#4 1,77#7 ,##1 1,75# 4,142" ,#5!6 ,4#5Sumber : Hasil Perhitungan
+ari ta-el diatas, didapatlkan nilai + &a8 = ,#57
+ari ta-el nilai kritis untuk uji $&irno;'ol&ogoro,
a* Antuk a = 5 > C +%r = ,4#
-* Antuk a = 1 > C +%r = ,4!6
arena +%r hitung D +%r ta-el &aka distri-usi diteri&a*
$. ji Chi S
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LogX = 1,6#"#
$d = ,4!!
s = *74
$e-aran peluang untuk 4 kelas
$ehingga ;aria-el data penga&atan dapat dikelo&pokkan se-agai -erikut:
a* $u- kelo&pok 1 (, H 45,647)
-* $u- kelo&pok 2 (45,647 H 4#,"52)
%* $u- kelo&pok " (4#,"52 H 5",44)
d* $u- kelo&pok 4 (5",44 H I )
Tabe 4.5. Perhitungan ji Keseuaian Distribusi Chi S !!?>3&>%$%@&>
' 45,647 2,5 " ,1
45,647 ' 4#,"52 2,5 1 ,#
4#,"52 ' 5",44 2,5 4 ,#
5",44 ' I 2,5 2 ,1
'u#ah 1 2,
Sumber : Hasil Perhitungan
+ari ta-el diatas didapatkan @2 hitung = 2,
+ari ta-el Aji hi $Euare didapatkan nilai:
a* Antuk a = 1 > C @2 ta-el 1",277
-* Antuk a = 5> C @2 ta-el #,4!!
arena @2 hitung D @2 ta-el &aka distri-usi diteri&a
4.1.. (eto)e (ononobe )an Kur;a Intensitas
Metode Monono-e dite&ukan oleh +r* Monono-e dari epang, Monono-e
&eneliti se-aran hujan di Filaah +0$ epang dan &ene&ukan &etode esti&asi hujan ja&'ja&an* +engan &etode Monono-e ini kita dapat &engesti&asi hujan setiap ja&na
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24 ×= T t
t ! !t
5!
dari hujan satuan ang ada* Monono-e &eru&uskan or&ulasi se-agai -erikut
(Li&antara, 21):
= / 24248(24t)n
= intensitas %urah hujan (&&ja&)
t = Faktu konsentrasi hujan (ja&), untuk ndonesia 5'7 ja&
/ 24 = %urah hujan &aksi&u& dala& 1 hari (&&ja&)
n = tetapan (untuk indonesia diperkirakan 2")
$e-aran hujan ja&'ja&an dipakai &odel Monono-e, dengan ru&us:
dengan:
/ t = ntensitas hujan rata'rata dala& ja& (&&ja&)
/ 24 = urah hujan eekti dala& satu hari (&&)
t = Jaktu &ulai hujan (ja&)
= Jaktu konsentrasi hujan (ja&)
Antuk daerah di ndonesia rata'rata t = 6 ja&, &aka:
= 1 ja& / 1 = / 246*(61)2" = ,55 */ 24
= 2 ja& / 2 = / 246*(62)2" = ,"47*/ 24
= " ja& / " = / 246*(6")2" = ,265 */ 24
= 4 ja& / 4 = / 246*(64)2" = ,21! */ 24
= 5 ja& / 5 = / 246*(65)2" = ,1!! */ 24
= 6 ja& / 6 = / 246*(66)2" = ,167 */ 24
+istri-usi hujan ja&'ja&an dihitung untuk &endapatkan hidrogra -anjir
ran%angan dengan %ara unit hidrogra, untuk &endapatkan %urah hujan ja&'ja&an
dihitung !ational "ethod dianggap hujan terpusat sela&a 6 ja& setiap hari dengan
ru&us se-agai -erikut:
a* /erata hujan sa&pai ja& ke &aka:
/t = /o (t
6 ) 2"
dengan: /t = intensitas hujan sela&a t ja& (&&ja&)
t = la&a hujan (ja&)
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/o = hujan harian rerata (&&) =6
24 !
/ 24 = hujan harian eekti
-* urah hujan ja& ke t ialah
/ t = t * /t H (t H 1) */ ( t H 1 )
dengan : / = %urah hujan pada ja& ke t (&&)
/t = intensitas hujan sela&a t ja&
= la&ana hujan (ja&)
/ ( t H 1 ) = intensitas hujan sela&a (t'1) ja&*
Prosentase Hujan 'a#3'a#an
/u&us
dengan / t = prosentase intensitas
1 ja& / 1 = (1 8 ,55/ 24) ' ((1'1) 8 / )
= ,55/ 24 H
= ,55 8 1> = 55 >2 ja& / 2 = (2 8 ,"47/ 24) ' ((2'1) 8 ,55/ 24)
= *6#4/ 24 ' *55/ 24
= ,14" 8 1> = 14>
" ja& / " = (" 8 ,265/ 24) ' (("'1) 8 ,"47/ 24)
= ,7#5/ 24 H ,6#4/ 24
= ,1 8 1> = 1>
4 ja& / 4 = (4 8 ,21!/ 24) ' ((4'1) 8 ,265/ 24)
= ,!72/ 24 H ,7#5/ 24 = ,! 8 1> = ! >
5 ja& / 5 = (5 8 ,1!!/ 24) ' ((5'1) 8 ,21!/ 24)
= ,#4/ 24' ,!72/ 24
= *67 8 1> = 7 >
6 ja& / 6 = (6 8 *167/ 24) ' ((6'1) 8 *1!!/ 24)
= ,5# 8 1> =6>
Tabe 4.7. Harga Prosentase Intensitas !* t%
/ t = (t 8 / t) ' ((t'1)(/ t'1))
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Tabe 4.8. Perhitungan
Hujan 'a#3'a#an (eto)e
(ononobe
'a#
Ke*asio
Ko#uatif Hujan 'a#3'a#an !##@ja#%
1:9 1:// $ 4 19
1 55> 55> 1",5#4 15,72 16,2#6 17,646 17,#2# 1!,!65
2 "5> 14> !,564 #,4#5 1,266 11,116 11,2#4 11,!!14
" 26> 1> 6,5"5 7,246 7,!"4 !,4!" !,61# #,672
4 22> !> 5,"#5 5,#!1 6,467 7," 7,115 7,4!4!1
5 1#> 7> 4,64# 5,155 5,57" 6,"5 6,1"2 6,4521
6 17> 6> 4,117 4,565 4,#"5 5,"44 5,4" 5,711#!
Hujan *an0angan !##% 41,16#6 45,647" 4#,"51! 5",441 54,2#75# 57,11#!
Koefisien Pengairan ,6 ,6 ,6 ,6 ,6 ,6
Hujan &fe"tif !##% 24,72 27,"!! 2#,611 "2,64 "2,57# "4,272
Sumber : Hasil Perhitungan
Contoh Perhitungan
/ ran%angan 1*5 th = 41,16# &&
= ,6 kaFasan pe&uki&an kepadatan
sedang
(didapatkan dari a-el oeisien Pengaliran,
su&-er: +rainasi Perkotaan, r* $* .indarko)
/ e 1*5 th = / ran%angan 8
= 41,16# 8 ,6
= 24,72 &&
/ ja&'ja&an 1*5 th = / t 8 / e 1*5 th
= 55> 8 24,72
= 1",5#4 &&
'a# "e3 * t !2%
1 55
$ 14
/ 1
4 !
7
5 6
'u#ah 1
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Ga&-ar 4*1* Graik ur;a ntensitas
4.$. Perhitungan Perta#bahan 'u#ah Pen)u)u"
4.$.1. Geometric Rate of Growth !Pertu#buhan =eo#etri%
/u&us: Pn + Po !1-r%n
dengan:
Po : ju&lah penduduk pada aFal tahun
r : angka pertu&-uhan penduduk (>)
n : ju&lah Faktu dala& tahun
Pn : ju&lah penduduk tahun n
ontoh Perhitungan:
+iketahui pada tahun 2#, ju&lah penduduk 52 jiFa dengan laju pertu&-uhan
penduduk " >, &aka proeksi ju&lah penduduk pada tahun 2# adalah se-agai
-erikut:
Pn + Po !1-r%n
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= 52 * (19,")7
=6415 jiFa
Tabe 4.19. Perhitungan Proe"si Pen)u)u" (eto)e =eo#etri
No. Tahun'u#ah Pen)u)u" !Pn%
!'ia%
$998 $99
1 21 6415
2 211 7#14
" 212 #76"
4 21" 1244
5 214 14!5!
6 215 1!""
7 216 2261"
Sumber : Hasil Perhitungan
4.$.$ Exponential Rate of Growth !Pertu#buhan &"sonensia%
/u&us: Pn + Po.ern
dengan:
Po : ju&lah penduduk pada aFal tahun
r : angka pertu&-uhan penduduk (>)
n : ju&lah Faktu dala& tahun
Pn : ju&lah penduduk tahun n
ontoh Perhitungan:
+iketahui pada tahun 2!, ju&lah penduduk 6 jiFa dengan laju pertu&-uhan
penduduk ",6>, &aka proeksi ju&lah penduduk pada tahun 2# adalah se-agai
-erikut:
Pn + Po.ern
= 52 * 2,71!," * 7
= 6415 jiFa
Tabe 4.11. Perhitungan Pertu#buhan Pen)u)u" (eto)e &"sonensia
No Tahun'u#ah Pen)u)u" !Pn%
'ia
$998 $99
1 21 6415
2 211 7#14
" 212 #76"
4 21" 1244
5 214 14!5!
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No Tahun'u#ah Pen)u)u" !Pn%
'ia
6 215 1!""
7 216 2261"
Sumber : Hasil Perhitungan
4./. Perhitungan Luas Tata =una Lahan Daerah Per"otaan
Pe&-agian tata guna lahan:
Luas Pengaruh $tasiun : 71,5625 k&2
Luas Pengaruh $tasiun : 65, k&2
Luas Pengaruh $tasiun + : !5, k&2
Luas Pengaruh $tasiun 3 : "6,4125 k&2
Luas otal : 257,#75 k&2
4.4. Perhitungan Pa)a (asing3#asing *en0ana Sauran Drainase Per"otaan
4.4.1. S"e#a Sauran Drainase a)a Daerah ang Diren0ana"an
ambar !encana saluran rencana dapat dilihat pada lampiran
4.4.$. Intensitas Hujan )an Ea"tu Konsentrasi
+istri-usi hujan &enggunakan &etode Log Pearson, perhitungan dan hasil
terdapat pada a- 4*1 Perhitungan urah .ujan*
Perhitungan area &enurut tata guna lahanna:
1* Kona Peru&ahan
a* Luas angunan
-* Luas a&an
2* Kona asa
a* Lapangan
-* a&an
"* Kona ndustri
a* Luas -angunan
4* alan /aa
a* alan 0spal
-* alan /u&put
5* Lahan osong
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ntensitas %urah hujan ( ) &enggunakan ru&us Monono-e:
= "2
24 2424
t
!
dengan:
= intensitas %urah hujan (&&ja&)
t = durasi %urah hujan (ja&)
/ 24 = %urah hujan &aksi&u& dala& 24 ja& (&&)
0ir hujan ang jatuh pada suatu daerah aliran, pada saat &enentuh per&ukaan
daerah aliran ang paling jauh lokasina dari &uara, &aka Faktu konsentrasina &ulai
dihitung, Faktu ini dise-ut to aitu a"tu i#asan er#u"aan* +ari sini air
&engalir &enuju &uara, dan Faktu ang diperlukan untuk &engalir didala& saluran
drainasi sa&pai &uara daerah aliran dise-ut a"tu i#asan sauran atau td*
Penju&lahan Faktu terse-ut &erupakan a"tu "onsentrasi atau t%*
t% = to 9 td
Ea"tu i#asan er#u"aan to
esarna tergantung pada -e-erapa aktor penentu:a* arak aliran sa&pai saluran terdekat
-* e&iringan per&ukaan daerah aliran
%* oeisien pengaliran daerah aliran
e-erapa siat Faktu li&pasan per&ukaan se-agai -erikut:
a* $e&akin %ura& daerah aliran se&akin ke%il to
-* $e&akin -esar resapan kedala& daerah aliran, atau se&akin ke%il koeisien
pengaliran, &aka se&akin -esar to*%* $e&akin jauh jarak li&pasan per&ukaan, &aka se&akin -esar to*
Ea"tu i#asan sauran t)
$etelah &eli&pas pada per&ukaan daerah aliran, &aka aliran air &asuk ke
dala& saluran drainasi dan &engalir &enuju &uara* Jaktu li&pasan saluran ini
tergantung pada: ukuran, jenis, -entuk, ke&iringan dasar, dan -ahan saluran*
Ea"tu "onsentrasi t0
Antuk daerah aliran ke%il dengan pola drainasi sederhana, la&a Faktu
konsentrasi -isa sa&a dengan la&a Faktu pengaliran dari te&pat ang terjauh* nilah
salah satu se-a- ru&us rasional hana dapat digunakan untuk daerah aliran ke%il*
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t% = *1#5
77*
S
L
dengan:
L = panjang pengaliran (&)
$ = ke&iringan pengaliran
4.4./. Luas Ca"uan: Panjang: Slope: )an Debit *en0ana
Panjang )an Slope Sauran
ontoh perhitungan slope di P1 :
3le;asi 0Fal = 9 1",!46
3le;asi 0khir = 9 1",62
Panjang $aluran = " &
Slope =
="
1",62)'(1",!46
= ,75
Tabe 4.1$. Perhitungan Panjang )an Slope Sauran
Daerah !1%Sauran
!$%&e;asi Aa !/%
&e;asi A"hir
!4%
'ara"
!%Soe !5%
Peru#ahan P1 1",!46 1",62 ", ,75
P2 1",62 1",#4 !, ,66
P" 1",!46 1","2 !, ,66
P4 1","2 1",#4 ", ,75
P5 1",#4 12,72" "6,! ,11
P6 1",!!! 1",41 7, ,7P7 1",41 1",1!" ", ,72
P! 1",!!! 1",6!" ", ,6!
P# 1",6!" 1",1!" 7, ,71
P1 1",1!" 1",27 1#,# ,7#
P11 1",255 12,7"6 !, ,65
P12 12,7"6 12,57 ", ,76
P1" 1",255 1",27 ", ,76
P14 1",27 12,5! !, ,65
P15 12,5! 12,266 25,4 ,#5
P16 14,1"! 1",56" 6, ,#6
P17 1",56" 1",4# ", ,24
P1! 14,1!" 14,!4 ", ,""
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P1# 14,!4 1",4# 6, ,##
P2 1","22 1",14# 17,5 ,##
P21 1","21 12,!6" 6, ,76
P22 12,!6" 12,665 ", ,66
P2" 1","21 1",14# ", ,57
P24 1",14# 12,665 6, ,!1
P25 12,665 12,4" 2#,1 ,!1
P26 12,66" 12,245 !, ,52
P27 12,245 11,#!# ", ,!5
P2! 12,66" 12,47 ", ,!5
P2# 12,47 11,#!# !, ,52
P" 11,#!# 11,7"# 2#, ,!6P"1 1","" 12,71 7, ,!!
P"2 12,71 12,56# ", ,47
P"" 1","" 1",241 ", ,"
P"4 1",241 12,56# 7, ,#6
P"5 12,461 12,"47 14,! ,77
P"6 12,545 12,1#1 5, ,71
P"7 12,1#1 11,#77 ", ,71
P"! 12,545 12,"47 ", ,66
P"# 12,"47 11,#77 5, ,74
P4 11,#77 11,764 24,4 ,!7
P41 12,26 11,7"# 6, ,4!
P42 11,7"# 11,475 ", ,!!
P4" 12,26 11,764 ", ,!7
P44 11,454 1,#25 6, ,!!
P45 11,764 11,475 5"," ,54
P46 12,1!1 12,2# ", ,51
P47 12,2# 1,6!2 14, ,#6
P4! 12,1!1 1,!75 14, ,#"
P4# 1,!75 1,6!2 ", ,65P5 1,6!2 1,461 55,5 ,4
P51 11,521 11,45# ", ,21
P52 11,45# 1,"#1 1#,2 ,#!
P5" 11,521 1,461 1#,2 ,#7
P54 1,461 1,"#1 ", ,2"
P55 1,"#1 1,2# 5,7 ,2
In)ustri
1 12,7"# 12,"6 5, ,!7
2 12,"6 11,!71 #, ,4!
" 12,7"# 12,6#5 #, ,5
4 12,"5 11,!71 5, ,!7
5 11,!71 11,61! 51,7 ,4#
'asa 1 1,#25 1,2# 6, ,16
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2 1,2# 1,65 1, ,22
" 1,#25 1,722 1, ,2
4 1,722 1,65 6, ,1#
5 1,65 #,!4! 6,1 ,"6
Laangan
L1 12,4" 11,5"" !, ,64
L2 11,5"" 1,##6 1, ,54
L" 12,4" 11,527 6, ,!6
L4 11,527 1,##6 6, ,!!
L5 1,##6 1,76 46," ,51
(ain)rainM1 1,76 #,!4! #1, ,1
M2 #,!4! #,774 "5,# ,21
Saah
$1 1",521 1",!" 5, ,!!$2 1",!" 12,7#4 6, ,4!
$" 1",521 1",2"2 6, ,4!
$4 1",2"2 12,7#4 5, ,!!
$5 12,7#4 12,6!! 22, ,4!
eterangan:
1 ata Guna Lahan 4 3le;asi 0khir
2 o&or $aluran 5 Panjang $aluran (&)
" 3le;asi 0Fal 6 ("'4)5
Luas Ca"uan
ontoh perhitungan saluran P*1 (Peru&ahan)
+iketahui:
Luas /u&ah = u&lah /u&ah 8 15 &2 = 8 15 &2 = , &2
Luas angunan = 6> 8 Luas /u&ah = 6> 8 &2 = , &2
Luas .ala&an = 4> 8 Luas /u&ah = 4> 8 &2 = , &2
Luas alan 0spal = Le-ar 8 ,! 8 Panjang = 8 ,! 8 8 14#,!2 = 11#,!6 &2
( karena di P1 tidak ada jalan, kalau ada jalan dikali dengan le-ar dan panjang jalan)
Luas alan /u&put = Le-ar 8 ,2 8 Panjang= & 8 ,2 8 8 14#,!2 & = 2#,#6 &2
( karena di P1 tidak ada jalan, kalau ada jalan dikali dengan le-ar dan panjang jalan)
Luas Lahan osong = 625," &2
L (panjang saluran) = " &
s = ,75
• % =77*
6
1#5,
s
L
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6!
=
77*
75,
"
6
1#5,
= ,72 ja&
• ="
2
24 24
24
Tc
!
="
2
72,
24
24
4!,!6!
= #7,5"4 &&ja&
• oeisien ga-ungan (F):
Area C
Bangunan 9:7
Haa#an 9:/
'aan Asa 9:8
'aan *u#ut 9:$
Lahan Kosong 9:/
F = ((Luas -angunan 8 -angunan) 9 (Luas hala&an 8 hala&an) 9 (Luas aspal
8 aspal) 9 (Luas ru&put 8 ru&put) 9 (Luas lahan kosong 8 lahan
kosong)) (Luas -angunan 9 Luas hala&an 9 Luas aspal 9 Luas ru&put
9 Luas lahan kosong)
= ((, 8 ,!) 9 (, 8 ,"5) 9 (11#,!6 8 ,#) 9 (2#,#6 8 ,2) 9 (625,"
8 ,"5)) (, 9 , 9 11#,!6 9 2#,#6 9625,")
= ,42#
• Luas Ga-ungan (0)
= Luas -angunan 9 luas hala&an 9 luas aspal 9 luas ru&put 9 luas lahan
kosong
= , 9 , 9 11#,!6 9 2#,#6 9 625,"
= 774,!5 &2
• +e-it .ujan Ga-ungan
N = ,27! 8 F 8 8 0 16
= ,27! 8 ,42# 8 #7,5"4 8 774,!5 16
= ,# &"dt
Antuk perhitungan selanjutna dapat dilihat pada ta-el 4*1"*
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Tabe 4.1/. Perhitungan Debit Hujan *an0angan Kaa ang Tahun
Daerah
!1%
Sauran
!$%
Luas
*u#ah!/%
Luas
Bangunan!4%
Luas
Haa#an !%
Luas 'aan
Asa!5%
Luas 'aan
*u#ut!6%
Luas Lahan
Kosong!7%
T0
!8%
I
!19%
C
!11%
Luas
=abungan !1$%
F
gabungan!1/%
#$ #$ #$ #$ #$ #$ !ja#% !##@ja#% #$ !#/@)t%Peru#aha
nP1 , , , 11#,!6 2#,#6 625," ,72 #7,5"4 ,42# 774,!5 ,#
P2 24, 144, #6, 274,52 6!,6" 7!!,"1 ,162 56,#" ,57" "5"1,46 ,"2
P" , , , , , 2421,"6 ,162 56,#14 ,"5 2421,"6 ,1"4
P4 , , , 44," 11,7 "2",62 ,72 #7,4!# ,6! !7",## ,144
P5 , , , 2#,"4 7,"" , ,76 #4,62" ,76 "6,67 ,7
P6 , , , 1#5,7" 4!,#" 277," ,14" 61,!52 ,"#" 2"21,6# ,157
P7 21, 126, !4, 1"7,!1 "4,45 1"1,6 ,74 #6,512 ,615 24",!6 ,"#7
P! , , , , , 1!6",6 ,75 #5,126 ,"5 1!6",6 ,172
P# , , , 412,5 1",1" 1!"6,# ,142 62,2"7 ,44 2"51,72 ,17#
P1 , , , 27,51 6,!! , ,52 121,766 ,76 "4,"# ,#
P11 , , , 2",6# 5,#2 176!,45 ,16" 56,77 ,42 22",6 ,12!
P12 24, 144, #6, 144,!2 "6,2 1#7,4 ,72 #7,!"1 ,61 277!,42 ,461
P1" , , , 145,24 "6,"1 25",25 ,72 #7,765 ,521 4"4,! ,62
P14 , , , 26!,51 67,1" #"4,!4 ,16" 56,72 ,45! 127,4! ,#2
P15 , , , 2!,25 7,6 , ,5! 112,!56 ,76 "5,"1 ,!
P16 , , , 1!1,74 45,4" "2,!2 ,11" 72,67! ,526 52#,## ,56P17 1!, 1!, 72, 124,54 "1,1" 12",2 ,112 72,772 ,615 27!,6# ,25!
P1! , , , , , 416,61 ,## 7!,#6 ,"5 416,61 ,"2
P1# , , , 154,1 "!,52 #76,!# ,111 7",261 ,41! 116#,51 ,##
P2 , , , ",!" 7,71 , ,4" 1"7,765 ,76 "!,54 ,11
P21 , , , 144,66 "6,16 11#,1 ,12" 6!,51 ,47 12!#,!" ,1
P22 , , , 1"4,1" "",5" ""5,"2 ,76 #4,"1# ,4!7 52,#! ,64
P2" , , , 124,62 "1,15 171,1 ,!1 #,!2 ,545 "26,!7 ,45
P24 1!, 1!, 72, 21",! 5",45 !5"," ,12 6#,5"4 ,554 2#2,55 ,"1"
P25 , , , 2!,4! 7,12 , ,6# 1,754 ,76 "5,6 ,!
P26 , , , 1!7,#7 46,## 1"!,11 ,177 5",64# ,412 154",7 ,#5
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Daerah !1%
Sauran!$%
Luas
*u#ah
!/%
Luas
Bangunan
!4%
Luas
Haa#an
!%
Luas 'aan
Asa
!5%
Luas 'aan
*u#ut
!6%
Luas Lahan
Kosong
!7%
T0
!8%
I
!19%
C
!11%
Luas
=abungan
!1$%
F
gabungan
!1/%
#$ #$ #$ #$ #$ #$ !ja#% !##@ja#% #$ !#/@)t%
P27 24, 144, #6, 12#,41 "2,"5 147,51 ,6# 1,64 ,614 27#,27 ,465
P2! , , , 1"",#1 "",4! 2",42 ,6# 1,64 ,5"5 "7,!1 ,56
P2# , , , 227,5" 56,!! 1!#,!6 ,177 5",64# ,4"5 1"74,27 ,!#P" , , , 26,6! 6,67 , ,67 12,76# ,76 "","5 ,7
P"1 , , , 2"4,61 5!,65 111!, ,1"1 65,776 ,4"5 1411,26 ,112
P"2 , , , 124,"# "1,1 !",16 ,!7 !6,475 ,617 2"!,65 ,"5
P"" , , , , , "5#,#4 ,14 76,6#2 ,"5 "5#,#4 ,27
P"4 , , , 1!5,"7 46,"4 6"",#" ,127 67,174 ,46 !65,64 ,74
P"5 , , , 26,1 6,5" , ,42 14,!4 ,76 "2,6" ,1
P"6 , , , 1"6,"6 "4,# 576,6 ,11 7",!2 ,444 746,51 ,6!
P"7 15, #, 6, 122,75 ",6# 21!,"" ,74 #6,156 ,6 1!71,77 ,"
P"! , , , 12,4! ",12 1!2,"5 ,76 #4,1!5 ,5"5 ""2,#5 ,47
P"# , , , 1!1,2 45,26 7!1,7# ,1! 74,6#4 ,442 1!,7 ,#"
P4 , , , 2!,42 7,11 , ,5! 112,6" ,76 "5,5" ,!
P41 , , , 165,66 41,41 716,15 ,147 6,!# ,442 #2",22 ,6#
P42 1!, 1!, 72, 1!,26 27,6 155,12 ,6! 11,41# ,6# 2#,44 ,"5#
P4" , , , 127,#4 "1,#! 111,! ,6! 11,"2 ,5#1 271,72 ,45
P44 , , , 161,# 4,4! 657,#7 ,116 71,117 ,446 !6,"5 ,76
P45 , , , 2#,5" 7,"! , ,12! 66,67" ,76 "6,#1 ,5
P46 , , , 217,46 54,"7 "476,47 ,!4 !!,7! ,"! "74!," ,"4#
P47 , , , "!!,62 #7,16 2#4",#2 ,216 47,!6 ,4! "42#,7 ,1!"
P4! , , , , , 457,5 ,21! 46,711 ,"5 457,5 ,1!4
P4# 42, 252, 16!, , , 15!,2 ,77 #",6#2 ,566 525!,2 ,775
P5 , , , 42,42 1,61 , ,14# 6,"45 ,76 5"," ,7
P51 , , , "7,#7 76,## 2"2#,74 ,11# 7,44 ,4! 2714,7 ,216
P52 , , , 275,46 6!,!7 274,#6 ,177 5",715 ,"#6 "4#,2# ,1!
P5" , , , 4",5" 1,!! 2#2,#6 ,17! 5",61 ,411 "47,"7 ,2#
P54 ", 1!, 12, , , !!#,75 ,11" 72,276 ,55! "!!#,75 ,4"6
P55 , , , 2#,5" 7,"! , ,1!1 52,#6" ,76 "6,#1 ,4
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Sumber : Hasil Perhitungan
eterangan :
1 = ata Guna Lahan 5 = Luas .ala&an (&) # = (*1#5O(arak (Slope*5) ) *77) 6
2 = a&a $aluran 6 = Luas alan 0spal (&) 1 = /2424 8 (24 t%) (2")
" = Luas /u&ah (&) 7 = Luas alan /u&put (&) 11 = oeisien Ga-ungan
4 = Luas angunan (&) ! = Luas Lahan osong (&) 12 = Luas Ga-ungan
1" = *27! 8 F 8 8 0 ga-ungan 16 (&"dt)
Tabe 4.14. Perhitungan Debit Hujan *an0angan Kaa ang Tahun
Daerah
!1%
Sauran
!$%
LuasIn)ustri
!/%
LuasBangunan
!4%
LuasHaa#an
!%
Luas 'aanAsa
!5%
Luas 'aan*u#ut
!6%
Luas LahanKosong
!7%
T0
!8%
I
!19%
C
!11%
Luas=abungan
!1$%
Fgabungan
!1/%
#$ #$ #$ #$ #$ #$ !ja#% !##@ja#% #$ !#/@)t%
In)ustri
1 1125, 675, 45, 227,46 56,!6 #",# ,12 77,7! ,5" 2""#,41 ,26!
2 1125, 675, 45, 421," 15,"" 2"5,#2 ,2 4#,475 ,4! 42,55 ,264
" 1125, 675, 45, 6"1,27 157,!2 4226,1 ,4!4 27,4#" ,452 614,1# ,212
4 1125, 675, 45, , , 1##6,2# ,12 77,757 ,447 "121,2# ,"2
5 , , , 2!,25 7,6 , ,1" 66,26 ,76 "5,"1 ,5
Sumber : Hasil Perhitungan
eterangan :
1 = ata Guna Lahan 5 = Luas .ala&an (&) # = (*1#5O(arak (Slope*5) ) *77) 6
2 = a&a $aluran 6 = Luas alan 0spal (&) 1 = /2424 8 (24 t%) (2")
" = Luas /u&ah (&) 7 = Luas alan /u&put (&) 11 = oeisien Ga-ungan
4 = Luas angunan (&) ! = Luas Lahan osong (&) 12 = Luas Ga-ungan
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1" = *27! 8 F 8 8 0 ga-ungan 16 (&"dt)
Tabe 4.1. Perhitungan Debit Hujan *an0angan Kaa ang Tahun
Daerah
!1%Sauran
!$%
Luas
'asa
!/%
Luas
Bangunan
!4%
Luas
Haa#an
!%
Luas 'aan
Asa
!5%
Luas 'aan
*u#ut
!6%
Luas Lahan
Kosong
!7%
T0
!8%
I
!19%
C
!11%
Luas
=abungan
!1$%
F
gabungan
!1/%
#$ #$ #$ #$ #$ #$ !ja#% !##@ja#% #$ !#/@)t%
'asa
1 15, #, 6, "27,26 !1,!2 14#,!7 ,1! 74,564 ,51! ""##,#5 ,"65
2 15, #, 6, , , "11,## ,2#2 "!,5" ,4"! 461,## ,216
" 15, #, 6, , , "#"2,46 ,"" "7,572 ,425 54"2,46 ,241
4 15, #, 6, , , 574!,55 ,17 75,1!! ,46 724!,55 ,615
5 , , , ,! ,2 , ,164 56,47 ,76 1, ,
Laangan
L1 15, #, 6, "!1,!2 #5,45 274,55 ,164 56,456 ,47! 46!1,!2 ,"51
L2 15, #, 6, 42!,51 17,1" ""4,21 ,2! 4!,1!2 ,466 5"75,!5 ,""6
L" 15, #, 6, 2!,7! 52,2 645,61 ,117 7,671 ,56" 246,5# ,266
L4 15, #, 6, 4","6 17,5# 215,17 ,116 71,1#2 ,4## 41!!,12 ,414
L5 , , , 27,# 6,#7 , ,11! 7,5#4 ,76 "4,!7 ,5
Sumber : Hasil Perhitungan
eterangan :
1 = ata Guna Lahan 5 = Luas .ala&an (&) # = (*1#5O(arak (Slope*5) ) *77) 6
2 = a&a $aluran 6 = Luas alan 0spal (&) 1 = /2424 8 (24 t%) (2")
" = Luas /u&ah (&) 7 = Luas alan /u&put (&) 11 = oeisien Ga-ungan
4 = Luas angunan (&) ! = Luas Lahan osong (&) 12 = Luas Ga-ungan
1" = *27! 8 F 8 8 0 ga-ungan 16 (&"dt)
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Tabe 4.15. Perhitungan Debit Hujan *an0angan Kaa ang Tahun
Daerah
!1%
Sauran
!$%
Luas
(ain)rain
!/%
Luas
Bangunan
!4%
Luas
Haa#an
!%
Luas
'aan
Asa
!5%
Luas
'aan
*u#ut
!6%
Luas
Lahan
Kosong
!7%
T0
!8%
I
!19%
C
!11%
Luas
=abungan
!1$%
F
gabungan
!1/%#$ #$ #$ #$ #$ #$ !ja#% !##@ja#% #$ !#/@)t%
(an)rainM1 , , , , , , ,15" 5#,"44 , , ,
M2 , , , , , , ,1"7 6",7## , , ,
Sumber : Hasil Perhitungan
eterangan :
1 = ata Guna Lahan 5 = Luas .ala&an (&) # = (*1#5O(arak (Slope*5) ) *77) 6
2 = a&a $aluran 6 = Luas alan 0spal (&) 1 = /2424 8 (24 t%) (2")
" = Luas /u&ah (&) 7 = Luas alan /u&put (&) 11 = oeisien Ga-ungan
4 = Luas angunan (&) ! = Luas Lahan osong (&) 12 = Luas Ga-ungan
1" = *27! 8 F 8 8 0 ga-ungan 16 (&"dt)
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Perhitungan Debit Kotor Peru#ahan
Prosedur perhitungan:
+ata ang ada:
P (216) = 2261" jiFa
e-utuhan air -ersih = !5 ltorghari
0ir ang ter-uang = 75 > dari ke-utuhan air -ersih
Luas area peru&ahan = ,66 k&2
Perhitungan:
/ = u&lah Penduduk luas area
= 2261" ,66
= "41#!","62 jiFak&2
0ir -uangan = 1 8 75>
= 6",75 ltorghari
N per k&2 = / 8 air -uangan
= "41#!","62 8 6",75
= 21!14"#," ltharik&2
= ,252"" &"dtk&2
Antuk perhitungan selanjutna dapat dilihat pada ta-el 4*17*
Tabe 4.16. Perhitungan Debit Kotor Peru#ahan
No#or Luas * < F air "otor
Sauran (k&2) (jiFa k&2) (ltorghari) (&"dt)
1 2 " 4 6P1 , , 6",75 ,
P2 ,24 "575,217 6",75 ,66
P" , , 6",75 ,P4 , , 6",75 ,
P5 , , 6",75 ,
P6 , , 6",75 ,
P7 ,21 "6#,!14 6",75 ,5"
P! , , 6",75 ,
P# , , 6",75 ,
P1 , , 6",75 ,
P11 , , 6",75 ,
P12 ,24 "575,217 6",75 ,66
P1" , , 6",75 ,
P14 , , 6",75 ,
P15 , , 6",75 ,
P16 , , 6",75 ,
P17 ,1! 26"6,412 6",75 ,454
P1! , , 6",75 ,
P1# , , 6",75 ,
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No#or Luas * < F air "otor
Sauran (k&2) (jiFa k&2) (ltorghari) (&"dt)
1 2 " 4 6P2 , , 6",75 ,
P21 , , 6",75 ,
P22 , , 6",75 ,
P2" , , 6",75 ,
P24 ,1! 26"6,412 6",75 ,454
P25 , , 6",75 ,
P26 , , 6",75 ,
P27 ,24 "575,217 6",75 ,66
P2! , , 6",75 ,
P2# , , 6",75 ,
P" , , 6",75 ,P"1 , , 6",75 ,
P"2 , , 6",75 ,
P"" , , 6",75 ,
P"4 , , 6",75 ,
P"5 , , 6",75 ,
P"6 , , 6",75 ,
P"7 ,15 21#22,1 6",75 ,"7!
P"! , , 6",75 ,
P"# , , 6",75 ,
P4 , , 6",75 ,
P41 , , 6",75 ,
P42 ,1! 26"6,412 6",75 ,454P4" , , 6",75 ,
P44 , , 6",75 ,
P45 , , 6",75 ,
P46 , , 6",75 ,
P47 , , 6",75 ,
P4! , , 6",75 ,
P4# ,42 61"!1,62# 6",75 ,16
P5 , , 6",75 ,
P51 , , 6",75 ,
P52 , , 6",75 ,
P5" , , 6",75 ,
P54 ," 4"!44,21 6",75 ,757
P55 , , 6",75 ,
u&lah ,2"4 "41#!","62
Sumber : Hasil Perhitungan
eterangan:
1 = no&or saluran
2 = luas area %akupan (k&2)
" = kepadatan penduduk (jiFak&2)
4 = ke-utuhan air per orang per hari (ltoranghari)
5 = de-it air kotor (&"dt)
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Perhitungan Debit Kotor 'asa
Prosedur perhitungan:
+ata ang ada:
0ir ang ter-uang = " &"dt
Luas area asa = *44 k&
ontoh perhitungan +e-it otor per $aluran
+ata : (dia&-il %ontoh saluran 1)
0 (catchment# = 15 &2
0 (total) = 1** &2
0ir ang ter-uang = " &"dt
Maka:
+e-it kotor pada saluran 1 adalah:
= 0ir ang ter-uang 8 (00 total)
= " 8 (151**)
= ,12!4 &"dt
Antuk perhitungan selanjutna dapat dilihat pada ta-el 4*1!
Tabe 4.17. Perhitungan Debit Kotor 'asa
No#or
Luas
Area
F air
"otor
Sauran (k&$% (&"dt)
1 2 "
1 ,15 ,12!4
2 ,15 ,12!4
" ,15 ,12!44 ,15 ,12!4
5 , ,
L1 ,15 ,12!4
L2 ,15 ,12!4
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L" ,15 ,12!4
L4 ,15 ,12!4
L5 , ,Sumber : Hasil Perhitungan
eterangan:
1 = no&or saluran
2 = luas daerah %akupan
" = (luas arealuas total jasa) 8 air ang ter-uang
Perhitungan Debit Kotor In)ustri
Prosedur perhitungan:
+ata ang ada:
0ir ang ter-uang = " &"dt
Luas area ndustri = ,22 k&
ontoh perhitungan +e-it otor per $aluran
+ata: (dia&-il %ontoh saluran 1)
0 (catchment ) = 1125 k&2
0 (total) = *22 k&2
Maka:
+e-it kotor pada saluran 1 adalah:
= N -uangan 8 (00 total)
= 2,5 8 (*1125 *2#)
= ,1 &"dt
Antuk perhitungan selanjutna dapat dilihat pada ta-el 4*1#*
Tabe 4.18.Perhitungan Debit Air Kotor In)ustri
No#or Luas
F air
"otor
Sauran !"#$% !#/@)t%
1 2 "
1 ,11 ,15"1
2 ,11 ,15"1
" ,11 ,15"1
4 ,11 ,15"1
5 , ,
Sumber : Hasil Perhitungan
eterangan:
1 = no&or saluran
2 = luas daerah %akupan
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" = (luas daerah %akupanluas total industri) 8 de-it air -uangan
Perhitungan Debit *an0angan
ontoh Perhitungan:
$aluran Peru&ahan (P1)
+ata:
N air hujan = *#2 &"dt
N air otor = * &"dt
Maka:
N ran%angan = N air hujan 9 N air otor
= *#2 9 *= *#2 &"dt
Antuk perhitungan selanjutna dapat dilihat pada ta-el 4*2*
Tabe 4.$9. Perhitungan Debit *an0angan
Daerah Tata Na#aF air
hujan
F air
"otor
F
ran0angan
=una Lahan Sauran !#/@)t% !#/@)t% !#/@)t%
G1 G$ G/ G4 G
Peru#ahan P1 ,#2 , ,#2
P2 ,"2" ,66 ,"26"
P" ,1"41 , ,1"41P4 ,1441 , ,1441
P5 ,7" , ,7"
P6 ,157 , ,157
P7 ,"#6! ,5" ,421
P! ,1724 , ,1724
P# ,17# , ,17#
P1 ,!! , ,!!
P11 ,12!1 , ,12!1
P12 ,46# ,66 ,467
P1" ,616 , ,616
P14 ,#1! , ,#1!
P15 ,!4 , ,!4
P16 ,56" , ,56"
P17 ,25!4 ,454 ,26"
P1! ,"2 , ,"2
P1# ,##5 , ,##5
P2 ,112 , ,112
P21 ,11 , ,11
P22 ,642 , ,642
P2" ,45 , ,45
P24 ,"127 ,454 ,"17"
P25 ,76 , ,76
P26 ,#4# , ,#4#P27 ,4652 ,66 ,4712
P2! ,555 , ,555
P2# ,!#1 , ,!#1
P" ,72 , ,72
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P"1 ,112" , ,112"
P"2 ,"54 , ,"54
P"" ,26# , ,26#P"4 ,74" , ,74"
P"5 ,#7 , ,#7
P"6 ,6! , ,6!
P"7 ,"2 ,"7! ,"4
P"! ,467 , ,467
P"# ,#25 , ,#25
P4 ,!5 , ,!5
P41 ,6# , ,6#
P42 ,"5# ,454 ,"6"5
P4" ,45" , ,45"
P44 ,75# , ,75#
P45 ,52 , ,52P46 ,"4!5 , ,"4!5
P47 ,1!"2 , ,1!"2
P4! ,1!44 , ,1!44
P4# ,7747 ,16 ,7!5"
P5 ,6! , ,6!
P51 ,2157 , ,2157
P52 ,1!5 , ,1!5
P5" ,2!6 , ,2!6
P54 ,4"6" ,757 ,44"#
P55 ,41 , ,41
In)ustri
1 ,267# ,15"126 ,17##2
2 ,2642 ,15"126 ,17#54
" ,2122 ,15"126 ,174"5
4 ,"1! ,15"126 ,1!""1
5 ,4# , ,4#
'asa )an Laangan
1 ,"654 ,12! ,1"!62
2 ,2162 ,12! ,12"71
" ,24# ,12! ,12617
4 ,614# ,12! ,16"5!
5 ,1 , ,1
L1 ,"515 ,12! ,1"72"
L2 ,""57 ,12! ,1"565
L" ,2661 ,12! ,12!6#L4 ,41"# ,12! ,14"4!
L5 ,52 , ,52
(an)rainM1 , , ,
M2 , , ,
Sumber : Hasil Perhitungan
eterangan :
1 = daerah tata guna lahan 4 = perhitungan de-it air kotor
2 = no&or saluran 5 = " 9 4
" = perhitungan de-it kala ulang 5 tahun
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Perhitungan Debit *an0angan Tota
ontoh Perhitungan:
$aluran Peru&ahan (P2)
+ata:
Nran%angan P*1 = *# &"dt
Nran%angan P*" = *"26 &"dt
Maka:
N ran%angan total P*" = Nran% P*1 9 Nran% P*"
= *417 &"
dtAntuk perhitungan selanjutna dapat dilihat pada ta-el 4*1!*
Tabe 4.$1. Perhitungan Debit *an0angan Tota
Daerah Tata Na#aF
ran0angan Keterangan
F ran0angan
tota=una Lahan Sauran !#/@)t% !#/@)t%
G1 G$ G/ G4 G
Peru#ahan P1 ,# tetap ,#
P2 ,"26 P19P2 ,417
P" ,1"4 tetap ,1"4
P4 ,144 P"9P4 ,27!
P5 ,7 P29P49P5 ,72
P6 ,157 tetap ,157
P7 ,42 P69P7 ,55#
P! ,172 tetap ,172P# ,17# P!9P# ,"51
P1 ,# P79P#9P1 ,#1#
P11 ,12! tetap ,12!
P12 ,467 P59P119P12 ,12#7
P1" ,62 tetap ,62
P14 ,#2 P19P1"9P14 ,17"
P15 ,! P129P149P15 ,2"7!
P16 ,56 tetap ,56
P17 ,26" P169P17 ,"1#
P1! ,"2 tetap ,"2P1# ,## P1!9P1# ,1"1
P2 ,11 P179P1#9P2 ,462
P21 ,1 tetap ,1
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P22 ,64 P219P22 ,164
P2" ,45 tetap ,45
P24 ,"17 P29P2"9P24 ,!24
P25 ,! P229P249P25 ,##6
P26 ,#5 tetap ,#5
P27 ,471 P159P269P27 ,2#44
P2! ,56 tetap ,56
P2# ,!# P259P2!9P2# ,1141
P" ,7 P279P2#9P" ,4#2
P"1 ,112 tetap ,112
P"2 ,"5 P"19P"2 ,14!
P"" ,27 tetap ,27
P"4 ,74 P""9P"4 ,11
P"5 ,1 P"29P"49P"5 ,25#
P"6 ,6! tetap ,6!
P"7 ,"4 P"69P"7 ,"72
P"! ,47 tetap ,47
P"# ,#" P"59P"!9P"# ,"#!
P4 ,! P"79P"#9P4 ,77!
P41 ,6# tetap ,6#
P42 ,"6" P"9P419P42 ,4525
P4" ,45 tetap ,45
P44 ,76 P49P4"9P44 ,!##
P45 ,5 P429P449P45 ,542#
P46 ,"4# tetap ,"4#
P47 ,1!" P469P47 ,5"2
P4! ,1!4 tetap ,1!4
P4# ,7!5 P4!9P4# ,#7
P5 ,7 P479P4#9P5 ,15!
P51 ,216 tetap ,216
P52 ,1! P519P52 ,"#6
P5" ,2# tetap ,2#
P54 ,444 P59P5"9P54 ,2161
P55 ,4 P529P549P55 ,2561
In)ustri
1 ,17## tetap ,17##
2 ,17#5 192 ,"5#5
" ,174" tetap ,174"
4 ,1!"" "94 ,"577
5 ,5 29495 ,7176
'asa 1 ,1"!6 P4591 ,6!16
2 ,12"7 P559192 1,614
" ,1262 tetap ,1262
4 ,16"6 "94 ,2!#!
5 , 29495 1,"511
L1 ,1"72 tetap ,1"72
L2 ,1"57 L19L2 ,272#
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L" ,12!7 tetap ,12!7
L4 ,14"5 L"9L4 ,2722
L5 ,5 L29L49L5 ,5456
(an)rainM1 , L59M1 ,5456
M2 , 59M19M2 1,!#67
Sumber : Hasil Perhitungan
eterangan :
1 = tata guna lahan
2 = no&or saluran
" = de-it ran%angan (&"dt)
4 = peta tata guna lahan
5 = de-it ran%angan total (&"dt)
4.4.4. Di#ensi Sauran
4.4.4.1. Di#ensi Sauran Per#u"aan
ontoh perhitungan:
$aluran peru&ahan (P*1)
+ata:
N ren%ana = ,127 &"dt
Q = 1,
$ = ,1
k = 45, -h = 1
Maka :
0 = (-9Q h)O h
= 2 h2
P = - 9 2h O (Q291),5
= ",!2! h
/ = P $
=h
h
!2!4,"
22
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!"
= ,522 h
R = k 8 / 2" 8 $,5
= 45 8 (,522 h)2" 8 ,1,5
= 2,#1# h2"
N hitung = 0 8 R
= 2 h2 8 2,#1# h2"
= 5,!"! h!"
N hitung = N ren%ana
5,!"! h
!"
= ,126 &
"
dth = ,1 &
-h = 1
- = ,1 &
F = 1" h
= 1" (,1)
= ,"" &
anggul = 4" h= 4" (,1) = ,1"4 &
0 total = (- 9 ( Q 8 4" h))) 8 (4" h)
= (,1 9 (18 4"8,1)))8(4" 8 ,1)
= ,"1 &2
Antuk perhitungan selanjutna dapat dilihat pada ta-el 4*22*
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Tabe 4.$$. Perhitungan Di#ensi Sauran Drainase
Daerah
TataNa#a
F
ren0ana s " b@h
A @
Gh$
P @
Gh* Gh
V
Gh$@/F Gh7@/ h b 4@/ h
A
tota
=una
LahanSauran !#/@)t% !#% !#% !#% !#@)t% !#/@)t% !#% !#% !#% !#% !#$%
G1 G$ G/ G4 G G5 J G7 G8 G19 G11 G1$ G1/ G14 G1 G15 G16
Peru#ahan P1 ,# 1, ,75 45, 1, 2, ",!2! ,522 2,5"5 5,7 ,#" ,#" ,"1 ,124 ,27P2 ,417 1, ,66 45, 1, 2, ",!2! ,522 2,"66 4,7"" ,17 ,17 ,57 ,226 ,!#
P" ,1"4 1, ,66 45, 1, 2, ",!2! ,522 2,"67 4,7"5 ,111 ,111 ,"7 ,14! ,"!
P4 ,27! 1, ,75 45, 1, 2, ",!2! ,522 2,5"" 5,66 ,142 ,142 ,47 ,1!# ,6"
P5 ,72 1, ,11 45, 1, 2, ",!2! ,522 2,#"2 5,!6" ,1# ,1# ,6" ,254 ,11"
P6 ,157 1, ,7 45, 1, 2, ",!2! ,522 2,4"6 4,!72 ,116 ,116 ,"# ,155 ,42
P7 ,55# 1, ,72 45, 1, 2, ",!2! ,522 2,4!4 4,#67 ,1!6 ,1!6 ,62 ,24! ,1!
P! ,172 1, ,6! 45, 1, 2, ",!2! ,522 2,415 4,!2# ,121 ,121 ,4 ,161 ,45
P# ,"51 1, ,71 45, 1, 2, ",!2! ,522 2,465 4,#"1 ,157 ,157 ,52 ,2# ,76
P1 ,#1# 1, ,7# 45, 1, 2, ",!2! ,522 2,5#1 5,1!2 ,22 ,22 ,7" ,2#4 ,151
P11 ,12! 1, ,65 45, 1, 2, ",!2! ,522 2,"51 4,71 ,1# ,1# ,"6 ,146 ,"7
P12 ,12#7 1, ,76 45, 1, 2, ",!2! ,522 2,55 5,1 ,252 ,252 ,!4 ,""6 ,1#!
P1" ,62 1, ,76 45, 1, 2, ",!2! ,522 2,547 5,#4 ,!1 ,!1 ,27 ,17 ,2
P14 ,17" 1, ,65 45, 1, 2, ",!2! ,522 2,"5 4,7 ,242 ,242 ,!1 ,"2" ,1!"
P15 ,2"7! 1, ,#5 45, 1, 2, ",!2! ,522 2,!52 5,74 ,"4 ,"4 ,11 ,45 ,2!7P16 ,56 1, ,#6 45, 1, 2, ",!2! ,522 2,!5# 5,717 ,75 ,75 ,25 ,## ,17
P17 ,"1# 1, ,24 45, 1, 2, ",!2! ,522 1,4"" 2,!66 ,1!5 ,1!5 ,62 ,247 ,17
P1! ,"2 1, ,"" 45, 1, 2, ",!2! ,522 1,67! ","55 ,74 ,74 ,25 ,#! ,17
P1# ,1"1 1, ,## 45, 1, 2, ",!2! ,522 2,#4 5,!7 ,12 ,12 ,"4 ,1"6 ,"2
P2 ,462 1, ,## 45, 1, 2, ",!2! ,522 2,!#! 5,7#6 ,16" ,16" ,54 ,21! ,!"
P21 ,1 1, ,76 45, 1, 2, ",!2! ,522 2,54! 5,#6 ,#7 ,#7 ,"2 ,12# ,2#
P22 ,164 1, ,66 45, 1, 2, ",!2! ,522 2,"75 4,75 ,11# ,11# ,4 ,15# ,44
P2" ,45 1, ,57 45, 1, 2, ",!2! ,522 2,26 4,41" ,76 ,76 ,25 ,11 ,1!
P24 ,!24 1, ,!1 45, 1, 2, ",!2! ,522 2,62" 5,245 ,211 ,211 ,7 ,2!1 ,1"!
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!5
Daerah
TataNa#a
F
ren0ana s " b@h
A @
Gh$
P @
Gh* Gh
V
Gh$@/F Gh7@/ h b 4@/ h
A
tota
=una
LahanSauran !#/@)t% !#% !#% !#% !#@)t% !#/@)t% !#% !#% !#% !#% !#$%
G1 G$ G/ G4 G G5 J G7 G8 G19 G11 G1$ G1/ G14 G1 G15 G16
P25 ,##6 1, ,!1 45, 1, 2, ",!2! ,522 2,62 5,2"# ,226 ,226 ,75 ,"2 ,15#
P26 ,#5 1, ,52 45, 1, 2, ",!2! ,522 2,11 4,22 ,12 ,12 ,"4 ,1"6 ,"2P27 ,2#44 1, ,!5 45, 1, 2, ",!2! ,522 2,6#5 5,"# ,""6 ,""6 ,112 ,44! ,"52
P2! ,56 1, ,!5 45, 1, 2, ",!2! ,522 2,6#5 5,"# ,76 ,76 ,25 ,11 ,1!
P2# ,1141 1, ,52 45, 1, 2, ",!2! ,522 2,11 4,22 ,25! ,25! ,!6 ,"44 ,27
P" ,4#2 1, ,!6 45, 1,5 2,5 4,"2! ,57! 2,#1 7,25" ,"4 ,51 ,11" ,454 ,4"7
P"1 ,112 1, ,!! 45, 1, 2, ",!2! ,522 2,746 5,4#2 ,#! ,#! ,"" ,1"1 ,"
P"2 ,14! 1, ,47 45, 1, 2, ",!2! ,522 2,5 4,11 ,122 ,122 ,41 ,16" ,47
P"" ,27 1, ," 45, 1, 2, ",!2! ,522 1,5!7 ",174 ,7 ,7 ,2" ,#4 ,15
P"4 ,11 1, ,#6 45, 1, 2, ",!2! ,522 2,!61 5,722 ,#" ,#" ,"1 ,124 ,27
P"5 ,25# 1, ,77 45, 1, 2, ",!2! ,522 2,557 5,115 ,1"! ,1"! ,46 ,1!4 ,5#
P"6 ,6! 1, ,71 45, 1, 2, ",!2! ,522 2,456 4,#11 ,!5 ,!5 ,2! ,11" ,22
P"7 ,"72 1, ,71 45, 1, 2, ",!2! ,522 2,466 4,#"2 ,16 ,16 ,5" ,21" ,!
P"! ,47 1, ,66 45, 1, 2, ",!2! ,522 2,"6! 4,7"7 ,75 ,75 ,25 ,## ,17
P"# ,"#! 1, ,74 45, 1, 2, ",!2! ,522 2,51" 5,25 ,16" ,16" ,54 ,217 ,!"
P4 ,77! 1, ,!7 45, 1, 2, ",!2! ,522 2,72# 5,45! ,2" ,2" ,6! ,271 ,12!
P41 ,6# 1, ,4! 45, 1, 2, ",!2! ,522 2,2 4,4 ,#2 ,#2 ,"1 ,122 ,26P42 ,4525 1, ,!! 45, 1,5 2,5 4,"2! ,57! 2,#25 7,"12 ,"52 ,52! ,117 ,47 ,46#
P4" ,45 1, ,!7 45, 1, 2, ",!2! ,522 2,7" 5,461 ,7 ,7 ,2" ,#" ,15
P44 ,!## 1, ,!! 45, 1, 2, ",!2! ,522 2,74 5,4! ,214 ,214 ,71 ,2!6 ,14"
P45 ,542# 1, ,54 45, 2, ", 4,!2! ,621 2,41 7,22# ,"7# ,75! ,126 ,55 ,6"!
P46 ,"4# 1, ,51 45, 1, 2, ",!2! ,522 2,7! 4,157 ,166 ,166 ,55 ,222 ,!6
P47 ,5"2 1, ,#6 45, 1, 2, ",!2! ,522 2,!64 5,727 ,17" ,17" ,5! ,2"1 ,#"
P4! ,1!4 1, ,#" 45, 1, 2, ",!2! ,522 2,!1# 5,6"# ,117 ,117 ,"# ,156 ,4"
P4# ,#7 1, ,65 45, 1, 2, ",!2! ,522 2,"44 4,6!! ,2"4 ,2"4 ,7! ,"11 ,17
P5 ,15! 1, ,4 45, 1, 2, ",!2! ,522 1,!41 ",6!1 ,"2 ,"2 ,11 ,42 ,2!"
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!6
Daerah
TataNa#a
F
ren0ana s " b@h
A @
Gh$
P @
Gh* Gh
V
Gh$@/F Gh7@/ h b 4@/ h
A
tota
=una
LahanSauran !#/@)t% !#% !#% !#% !#@)t% !#/@)t% !#% !#% !#% !#% !#$%
G1 G$ G/ G4 G G5 J G7 G8 G19 G11 G1$ G1/ G14 G1 G15 G16
P51 ,216 1, ,21 45, 1, 2, ",!2! ,522 1,"" 2,66 ,164 ,164 ,55 ,21# ,!4
P52 ,"#6 1, ,#! 45, 1, 2, ",!2! ,522 2,!!7 5,774 ,154 ,154 ,51 ,26 ,74P5" ,2# 1, ,#7 45, 1, 2, ",!2! ,522 2,!76 5,752 ,122 ,122 ,41 ,162 ,46
P54 ,2161 1, ,2" 45, 1, 2, ",!2! ,522 1,414 2,!2! ,"!1 ,"!1 ,127 ,5! ,452
P55 ,2561 1, ,2 45, 1, 2, ",!2! ,522 1,"4 2,6! ,41# ,41# ,14 ,55! ,546
In)ustri
1 ,17## 1, ,!7 45, 1, 2, ",!2! ,522 2,71# 5,4"! ,27# ,27# ,#" ,"71 ,241
2 ,"5#5 1, ,4! 45, 1,5 2,5 4,"2! ,57! 2,16! 5,41# ,"62 ,542 ,121 ,4!2 ,4#4
" ,174" 1, ,5 45, 1, 2, ",!2! ,522 ,645 1,2#1 ,472 ,472 ,157 ,62# ,6#"
4 ,"577 1, ,!7 45, 1,5 2,5 4,"2! ,57! 2,#5 7,26" ,"2" ,4!5 ,1! ,4"1 ,"#5
5 ,7176 1, ,4# 45, 2, ", 4,!2! ,621 2,2#" 6,!! ,42! ,!57 ,14" ,571 ,!16
'asa
1 ,6!16 1, ,6!16 45, 2, ", 4,!2! ,621 27,5 !1,151 ,167 ,""" ,56 ,222 ,12"
2 1,614 1, 1,614 45, 2, ", 4,!2! ,621 "",756 11,26# ,1!1 ,"62 ,6 ,241 ,146
" ,1262 1, ,1262 45, 1, 2, ",!2! ,522 1,"6! 2,7"6 ,14! ,14! ,4# ,1#7 ,6!
4 ,2!#! 1, ,2!#! 45, 1, 2, ",!2! ,522 15,712 "1,424 ,172 ,172 ,57 ,2" ,#"
5 1,"511 1, 1,"511 45, 2, ", 4,!2! ,621 "!,!6 114,25# ,1!# ,"7# ,6" ,252 ,15#
L1 ,1"72 1, ,1"72 45, 1, 2, ",!2! ,522 1,!1" 21,626 ,15 ,15 ,5 ,2 ,7
L2 ,272# 1, ,272# 45, 1, 2, ",!2! ,522 15,24! ",4#6 ,171 ,171 ,57 ,227 ,#1L" ,12!7 1, ,12!7 45, 1, 2, ",!2! ,522 1,471 2,#42 ,14! ,14! ,4# ,1#! ,6!
L4 ,2722 1, ,2722 45, 1, 2, ",!2! ,522 15,22! ",456 ,17 ,17 ,57 ,227 ,#
(an)rain
L5 ,5456 1, ,5456 45, 2, ", 4,!2! ,621 24,22 72,66 ,16 ,"2 ,5" ,21" ,11"
M1 ,5456 1, ,1 45, 2, ", 4,!2! ,621 ",27# #,!"! ,""! ,676 ,11" ,451 ,5!
M2 1,!#67 1, ,21 45, 2, ", 4,!2! ,621 1,4# 4,46# ,725 1,45 ,242 ,#67 2,""7
Sumber : Hasil Perhitungan
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!7
eterangan:
1 = ata guna lahan 1 = ! 9 #
2 = no&or saluran 11 = 5 8 #2" 8 4,5
" = Perhitungan de-it ran%angan 12 = ! 8 11
4 = ta-el de Ros 1" = ("12)"!
5 = Slope ala&i 14 = 1" 8 7
6 = ta-el de Ros 15 = 1" "
7 = ta-el de Ros 16 = 1" 8 (4")
! = " 9 6 17 = (149(4816))816
# = 6 9 (28(("291),5))
4.4.4.$. Di#ensi Sauran Baah Per#u"aan
Perhitungan Di#ensi Tile Drain )an Drain Spacing
a* Perhitungan +i&ensi Tile %rain
+iketahui: +% = ,4# %&hari
= ,4# &hari
n = ,15
s = ,51
0 = ,6 .a
= 6 &2
Perhitungan:
Rolu&e = 0 8 +%
= 6 8 ,4#
= 2,#"2 &"hari
N = Rolu&e (248686)
= ,"#" &"detik
Luas (0) = r 2
P = r
/ = 0P
= r
N = (1n) 8 (r 2") 8 s,5 8 0
,# = (1,15) 8 (r 2") 8 ,51,5 8 r 2
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!!
,# = r !"
r = ,1" &
+ = ,26 &
Panjang lapangan = 1 &
arak = ",6!2 &
anakna pipa = 27 -uah pipa
-* Perhitungan +rain $pa%ing
+iketahui:
a = ," &hari n = ,15
- = ,"5 &hari s = ,1#
F = 1,1 & ++ = 7,! &
h = ," & r o = ,1 &
+% = ,4# &hari
E = 1> 8 / 24
= 1> 8 4!,!6!
= ,4!# &&hari
= ,4# &hari
+ = ++ H (F9h)
= 7 H (1,19,")
= 5,6 &
L2 = (!- 8 d*h 9 4a*h2) E
= (! 8 ,"5 8 ,5d 9 4 8 ,"8,"2
) ,4#
= 171!,#22 d 9 221,442!
Perhitungan dilakukan dengan %ara:
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!#
Menggunakan Graik o&ogra&
1* Men%ari nilai +h dan hu
+h = 5,6 ,"
= 1!,67
hu = h(r o8",14)
= ," ,4
= 7,424
+ari ta-el no&ogra&, dengan &elihat +h dan hu didapatkan titik
2* Men%ari nilai -d% dan ad%
-E = 716,2
aE = 61",#
"* Menghu-ungkan titik dari hasil point 1 dengan nilai -d% sa&pai
&e&otong nilai -d% dan ad%
+ari ta-el o&ogra& didapat:
LSh = 2
+engan nilai h = ," &
$ehingga nilai LS = 6
4* Menghu-ungkan nilai LSh dengan nilai ad% sa&pai &e&otong garis
aS
+ari ta-el no&ogra& didapat a = 1,"7
5* Menghitung nilai L
L = a 8 LS
= 62,22 &
Menghitung nilai dia&eter
L2 = (!- 8 d*h 9 4a*h2) E
= 171!,#22 d 9 221,4
$ehingga d = 2,12 &
+engan &elihat nilai:
Panjang lapangan olahraga = 1 &
Le-ar lapangan olahraga = 6 &
+ia&eter = ,26 &
arak antar Pipa = ",6!2 &
$ehingga diren%anakan ju&lah pipa = 27,161 = 27 -uah
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#
%* Perhitungan +i&ensi $aluran olektor
+ata :
Nren%ana = ,546 &"detik
Panjang sal*kolektor = 46," &
3le;asi aFal (titik tinggi) = 9 1,##6
3le;asi akhir (titik rendah) = 9 1,76
Q = 1
oe*Manning (n) = ,15
-h = 2
Maka :
Slope saluran kolektor =Saluran Pan&ang
Tinggi 'eda
=( )
",46
76,1##6,1 −
= ,51
0 = (-h9Q)
= " h2
P = -h 9 2 8 (Q291),5
= 4,!2! h
/ = P
$
=h
h
!2!,4
"2
= ,621 h
R =n
1 8 / 2" 8 $,5
=15,
1 8 (,522 h)2" 8 ,51,5
= ",466 h2"
N hitung = 0 8 R
= 2 h2 8 4,515 h2"
= 1,"## h!"
N hitung = N ren%ana
1,"## h!" = ,1 &"dt
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#1
h = ,546 &
-h = 1
- = ,662 &
F = 1" h
= 1" (,""1)
= ,11 &
anggul = 4" h
= 4" (,""1)
= ,441 & 0 total = (- 9 (- 9 (2 8 Q 8 4" h))) 8 (4" h)2
= (,662 9(,662 9(281,84" 8 ,""1)))8(4" 8 ,""1)2
= " &2
4.4.. Vou#e =aian )an Ti#bunan Serta Biaa Pe#buatan Sauran
Perhitungan Vou#e )an Biaa =aian !P.1%
+ata:
.arga galian tanah = /p* 16* &"
Panjang saluran = 2 &
0 = ,"1 &2
Maka :
• Rolu&e galian = L 8 0
= 2 8 ,"1 = ,627 &"
• iaa galian = Rolu&e galian 8 harga galian
= ,627 &
"
8 /p* 16* &
"
= /p* 1*"5,""
Antuk perhitungan selanjutna dapat dilihat pada ta-el 4*2"*
Tabe 4.$/. Perhitungan Vou#e )an Biaa =aian
Daerah Tata Na#a Panjang !L% Luas Vou#eBiaa
=una Lahan Sauran !#% !#$% !#/)
G1 G$ G/ G4 G G5Peru#ahan P1 ", ,27 ,!! /p "2*""6,15
P2 !, ,!# 7,152 /p 2!6*65,#4
P" !, ,"! ",56 /p 122*221,!#
P4 ", ,6" 1,!!" /p 75*"4,"1
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P5 "6,! ,11" 4,144 /p 165*761,#!
P6 7, ,42 2,#45 /p 117*!!,7#
P7 ", ,1! ",225 /p 12#*!,5P! ", ,45 1,"6" /p 54*5"",5"
P# 7, ,76 5,"42 /p 21"*677,25
P1 1#,# ,151 ",1 /p 12*"!4,!4
P11 !, ,"7 2,#6! /p 11!*721,1
P12 ", ,1#! 5,#44 /p 2"7*74",!!
P1" ", ,2 ,65 /p 24*27,#!
P14 !, ,1!" 14,615 /p 5!4*5!2,"1
P15 25,4 ,2!7 7,2#1 /p 2#1*645,55
P16 6, ,17 1,"! /p 41*54,46
P17 ", ,17 ",2 /p 12!*14,!4P1! ", ,17 ,56 /p 2*254,"5
P1# 6, ,"2 1,#"7 /p 77*4!1,14
P2 17,5 ,!" 1,452 /p 5!*!!,4#
P21 6, ,2# 1,742 /p 6#*667,!7
P22 ", ,44 1,""1 /p 5"*245,76
P2" ", ,1! ,5"" /p 21*"!,6"
P24 6, ,1"! !,2!4 /p ""1*"7,#
P25 2#,1 ,15# 4,6"5 /p 1!5*4",1!
P26 !, ,"2 2,571 /p 12*!25,44
P27 ", ,"52 1,547 /p 421*!62,76P2! ", ,1! ,5"7 /p 21*464,5
P2# !, ,27 16,5#2 /p 66"*6#!,#4
P" 2#, ,4"7 12,6!" /p 57*"15,#1
P"1 7, ," 2,#4 /p !"*76#,!7
P"2 ", ,47 1,"#5 /p 55*!14,2!
P"" ", ,15 ,46" /p 1!*521,71
P"4 7, ,27 1,!7! /p 75*11#,#"
P"5 14,! ,5# ,!7" /p "4*#22,1#
P"6 5, ,22 1,116 /p 44*641,47
P"7 ", ,! 2,"!# /p #5*545,6!
P"! ", ,17 ,51# /p 2*765,2"
P"# 5, ,!" 4,12! /p 165*1"1,75
P4 24,4 ,12! ",1"2 /p 125*2!5,41
P41 6, ,26 1,56! /p 62*71!,2#
P42 ", ,46# 14,61 /p 562*4"2,46
P4" ", ,15 ,456 /p 1!*2"5,25
P44 6, ,14" !,55# /p "42*"56,11
P45 5"," ,6"! "",#!4 /p 1*"5#*"6!,44
P46 ", ,!6 2,5!6 /p 1"*442,6#
P47 14, ,#" 1",27 /p 521*7#,56
P4! 14, ,4" 5,#56 /p 2"!*24!,#
P4# ", ,17 5,# /p 2"*6#,56
P5 55,5 ,2!" 15,72" /p 62!*#",6"
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P51 ", ,!4 2,522 /p 1*!#2,27
P52 1#,2 ,74 !,1 /p "2"*##2,24
P5" 1#,2 ,46 5,2 /p 2*7#!,5
P54 ", ,452 1",56" /p 542*525,75
P55 5,7 ,546 27,667 /p 1*16*6#!,
In)ustri
1 5, ,241 12,6! /p 4!2*722,55
2 #, ,4#4 44,442 /p 1*777*67!,#6
" #, ,6#" 62,"!4 /p 2*4#5*"7#,#!
4 5, ,"#5 1#,745 /p 7!#*7#,12
5 51,7 ,!16 42,171 /p 1*6!6*!27,47
'asa )an Laangan
1 6, ,12" 7,"#! /p 2#5*#26,"7
2 1, ,146 14,55! /p 5!2*"27,5#
" 1, ,6! 6,77! /p 271*114,56
4 6, ,#" 5,554 /p 222*177,77
5 6,1 ,15# #,57! /p "!"*1"7,14
L1 !, ,7 5,5#6 /p 22"*!"1,#5
L2 1, ,#1 #,51 /p "62*5#,55
L" 6, ,6! 4,#7 /p 16"*!7!,2!
L4 6, ,# 5,426 /p 217*22,4
L5 46," ,11" 5,252 /p 21*72,66
(an)rainM1 #1, ,5! 46,21# /p 1*!4!*761,5"
M2 "5,# 2,""7 !",# /p "*"55*#!!,51
Tota Biaa =aian /p 27*6!1*51,!"
Sumber : Hasil Perhitungan
Perhitungan Biaa Penutuan Sauran Dengan Beton !P.1%
+ata:
.arga -eton = /p* 12* &"
Panjang sal = " &
Maka:
o = - 9 (2 8 Q 8 h)
= ,#" 9 (2 8 1 8 ,#")
= ,"41 &
o Luas = L 8
= " 8 ,"41
= 1,2"7 &2
o iaa -eton = Luas 8
harga -eton= 1,2"7 &2 8 /p* 12* &2
= /p* 1,22!,4!4*65
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Antuk perhitungan selanjutna dapat dilihat pada ta-el 4*24*
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Tabe 4.$4. Perhitungan Biaa Peaisan Beton
Daerah Tata Na#a Panjang !L% A h
T b LuasBiaa Beton
=una Lahan Sauran !#% !#$% !#% !#% !#% !#$%
G1 G$ G/ G4 G G5 G6 G7 G8 G19
Peru#ahan P1 ", ,27 ,#" 1, ,"41 ,#" 1,2"7 /p 1*22!*4!4,65
P2 !, ,!# ,17 1, ,622 ,17 4#,724 /p 5*#66*!2,74P" !, ,"! ,111 1, ,46 ,111 "2,51 /p "*#*177,!#
P4 ", ,6" ,142 1, ,521 ,142 15,62" /p 1*!74*715,!4
P5 "6,! ,11" ,1# 1, ,6#! ,1# 25,671 /p "*!*571,5"
P6 7, ,42 ,116 1, ,426 ,116 2#,!4! /p "*5!1*!11,#7
P7 ", ,1! ,1!6 1, ,6!2 ,1!6 2,44! /p 2*45"*77,5"
P! ", ,45 ,121 1, ,44" ,121 1",2#5 /p 1*5#5*"55,"
P# 7, ,76 ,157 1, ,574 ,157 4,1## /p 4*!2"*!42,14
P1 1#,# ,151 ,22 1, ,!! ,22 16,!! /p 1*#"*5"",5"
P11 !, ,"7 ,1# 1, ,4 ,1# "2,"" /p "*!4"*#15,!5
P12 ", ,1#! ,252 1, ,#25 ,252 27,75# /p "*""1*42,!4
P1" ", ,2 ,!1 1, ,2#5 ,!1 !,!5! /p 1*62*#",4"
P14 !, ,1!" ,242 1, ,!!# ,242 71,!1 /p !*52#*6!,1#
P15 25,4 ,2!7 ,"4 1, 1,114 ,"4 2!,2# /p "*"#4*762,#7
P16 6, ,17 ,75 1, ,27" ,75 16,42 /p 1*#6!*2!4,64
P17 ", ,17 ,1!5 1, ,67# ,1!5 2,"6# /p 2*444*"6,74P1! ", ,17 ,74 1, ,27 ,74 !,12 /p #72*265,7
P1# 6, ,"2 ,12 1, ,"74 ,12 22,411 /p 2*6!#*2#5,67
P2 17,5 ,!" ,16" 1, ,5## ,16" 1,4! /p 1*257*56,75
P21 6, ,2# ,#7 1, ,"54 ,#7 21,251 /p 2*55*#7,64
P22 ", ,44 ,11# 1, ,4"! ,11# 1",1"7 /p 1*576*45,!7
P2" ", ,1! ,76 1, ,277 ,76 !,"1 /p ##7*24!,2#
P24 6, ,1"! ,211 1, ,772 ,211 46,"46 /p 5*561*567,2#
P25 2#,1 ,15# ,226 1, ,!" ,226 24,14" /p 2*!#7*14",4#
P26 !, ,"2 ,12 1, ,"7" ,12 2#,!11 /p "*577*""#,!!
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P27 ", ,"52 ,""6 1, 1,2"" ,""6 "6,#77 /p 4*4"7*221,!6
P2! ", ,1! ,76 1, ,27! ,76 !,"41 /p 1**!!#,!
P2# !, ,27 ,25! 1, ,#47 ,25! 75,7"! /p #*!!*56!,"1
P" 2#, ,4"7 ,"4 1, 1,41! ,51 41,11" /p 4*#""*555,!2
P"1 7, ," ,#! 1, ,"6 ,#! 25,17 /p "*2*"54,#
P"2 ", ,47 ,122 1, ,44! ,122 1",45 /p 1*61"*#!,2!
P"" ", ,15 ,7 1, ,25! ,7 7,74! /p #2#*74#,67P"4 7, ,27 ,#" 1, ,"4 ,#" 2",!"5 /p 2*!6*167,#
P"5 14,! ,5# ,1"! 1, ,55 ,1"! 7,472 /p !#6*6#!,6"
P"6 5, ,22 ,!5 1, ,"11 ,!5 15,52# /p 1*!6"*456,1
P"7 ", ,! ,16 1, ,5!7 ,16 17,5#7 /p 2*111*6#4,4"
P"! ", ,17 ,75 1, ,27" ,75 !,24 /p #!4*45,47
P"# 5, ,!" ,16" 1, ,5#7 ,16" 2#,!66 /p "*5!"*#77,"
P4 24,4 ,12! ,2" 1, ,745 ,2" 1!,17" /p 2*1!*771,6
P41 6, ,26 ,#2 1, ,""6 ,#2 2,16" /p 2*41#*567,2
P42 ", ,46# ,"52 1, 1,46! ,52! 44,2# /p 5*2!"*45,25
P4" ", ,15 ,7 1, ,256 ,7 7,6!! /p #22*5"2,
P44 6, ,14" ,214 1, ,7!5 ,214 47,1! /p 5*65"*7,!
P45 5"," ,6"! ,"7# 1, 1,76! ,75! #4,211 /p 11*"5*2!4,24
P46 ", ,!6 ,166 1, ,61 ,166 1!,"1 /p 2*1#7*22#,6#
P47 14, ,#" ,17" 1, ,6"4 ,17" !!,777 /p 1*65"*221,46
P4! 14, ,4" ,117 1, ,42# ,117 6,2# /p 7*2"*51,5P4# ", ,17 ,2"4 1, ,!56 ,2"4 25,6!# /p "*!2*652,#4
P5 55,5 ,2!" ,"2 1, 1,16 ,"2 61,4# /p 7*"6#*71,74
P51 ", ,!4 ,164 1, ,6" ,164 1!,!" /p 2*16#*#7",77
P52 1#,2 ,74 ,154 1, ,566 ,154 61,!25 /p 7*41!*#6!,72
P5" 1#,2 ,46 ,122 1, ,446 ,122 4!,672 /p 5*!4*5!,7
P54 ", ,452 ,"!1 1, 1,"#! ,"!1 41,#"" /p 5*"1*#4",1"
P55 5,7 ,546 ,41# 1, 1,5"6 ,41# 77,!5! /p #*"42*#"7,#
In)ustri 1 5, ,241 ,27# 1, 1,21 ,27# 51,64 /p 6*127*717,25
2 #, ,4#4 ,"62 1, 1,56 ,542 1"5,57! /p 16*26#*""2,17
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" #, ,6#" ,472 1, 1,7"1 ,472 155,766 /p 1!*6#1*#45,##
4 5, ,"#5 ,"2" 1, 1,"47 ,4!5 67,"57 /p !*!2*!15,"1
5 51,7 ,!16 ,42! 1, 1,### ,!57 1","5# /p 12*4"*!#,##
'asa )an
Laangan
1 6, ,12" ,167 1, ,777 ,""" 46,6"! /p 5*5#6*5",15
2 1, ,146 ,1!1 1, ,!45 ,"62 !4,46 /p 1*1"5*215,15
" 1, ,6! ,14! 1, ,541 ,14! 54,12 /p 6*4#4*4"4,5"
4 6, ,#" ,172 1, ,6"2 ,172 "7,#5 /p 4*55"*#77,25 6,1 ,15# ,1!# 1, ,!!4 ,"7# 5",111 /p 6*"7"*2!#,62
L1 !, ,7 ,15 1, ,55 ,15 4",#!" /p 5*27!*1!,#!
L2 1, ,#1 ,171 1, ,625 ,171 62,542 /p 7*55*7",2
L" 6, ,6! ,14! 1, ,54" ,14! "2,5#" /p "*#11*12,#2
L4 6, ,# ,17 1, ,625 ,17 "7,57 /p 4*5*!2!,5
L5 46," ,11" ,16 1, ,746 ,"2 "4,51! /p 4*142*1"7,#2
(an)rainM1 #1, ,5! ,""! 1, ,676 ,676 61,525 /p 7*"!"*1",27
M2 "5,# 2,""7 ,725 1, 1,45 1,45 52,65 /p 6*247*!4,#
Tota biaa beton/p ""6*1!5*742,1!
Sumber:Hasil Perhitungan
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4.4.5. =a#bar Potongan (e#anjang )an (eintang Sauran (Collector
Drain Channel dan Receptor Drain Channel)
=a#bar Detai )an S"e#a Sauran Drainase Per"otaan
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=a#bar Potongan (e#anjang )an (eintang Sauran (an)rain
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4.4.6. Peren0anaan Di#ensi Su#ur *esaan
onsep aFal peren%anaan su&ur resapan aitu se-agai pengganti tanah
resapan air hujan ang &engala&i perkerasan ang &ene-a-kan air hujan ang
jatuh tidak dapat langsung &eresap ke dala& tanah* Antuk &ereduksi li&pasan
ang terjadi di sekitar saluran drainase, &aka su&ur resapan di-angun di sekitar
saluran drainase di Filaah ang ter&asuk dala& daerah tangkapan air saluran
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terse-ut* erdasarkan perti&-angan dipilih konstruksi su&ur resapan dengan -atu
-ata karena dianggap dengan &enggunakan -atu -ata dapat &e&per%epat
re&-esan ang terjadi, dapat dipakai padase&ua jenis tanah, dan le-ih eisien
dala& hal ketersediaan &aterial dan pelaksanaan pekerjaan*
+e-it ang akan &asuk su&ur resapan diasu&si se-esar 1> dari %urah
hujan ran%angan kala ulang 5 tahun, tidak &e&perti&-angkan de-it air kotor*
Peren%anaan di&ensi su&ur resapan dala& tugas ini hana &enghitung untuk
daerah tata guna lahan peru&ahan dan jasa* Perhitungan di&ensi su&ur resapan
dan ju&lah su&ur resapan &enggunakan ru&us dala& $ "'245"'22*
ontoh Perhitungan:
+aerah Peru&ahan 1
• Luas lahan peru&ahan (0t) = 1#27, 61&2
• .ujan ran%angan (/) = 5,542 &&hari• F (koeisien ga-ungan) = ,641
+i&ensi $u&ur /esapan
• +ia&eter su&ur (d) = 1,1 &•
ari'jari su&ur (r) = ,55 &• edala&an air su&ur (.) = 1," &• edala&an su&ur resapan (.$/ ) = 1,5 &• aktor geo&etrik () = 2,2• oeisien per&ea-ilitas (k) = ,1 &dt
= ,!64 &&hari
• .ujan eekti (t%) = (,# 8 / ,#2) 6
= (,# 8 5,542,#2) 6
= ,72 ja&
• Luas $u&ur (0) = luas dinding su&ur 9 luas alas
= (",14 8 d 8 h) 9 (,25 8 ",14 8 d2
)= (",14 8 1,1 8 1,") 9 (,25 8 ",14 8 1,12)
= 5,445 &2
• Rolu&e air ang &eresap (Rrsp)
= (t% 24) 8 0 total 8 k 8 a%tor geo&etrik
= (,72 24) 8 5,445 8 ,!64 8 2,2
= ,"1 &"
• Rolu&e 0ir ang Meli&pas (Ra-)
= ,!55 8 F 8 0t 8 /
= (,!55 8 ,641 8 1#27,61 8 5,542)1
= 5,!5" &"
• . total = (Ra- H Rrsp) luas alas
= (5,!5" H ,"1) (,25 8 ",14 8 1,12)
= 6,15# &
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• u&lah $u&ur = . total . ren%ana
= 6,15# 1,"
= 5 -uah
Perhitungan selanjutna untuk penentuan ju&lah su&ur resapan pada daerah tata
guna lain se%ara lengkap disajikan pada ta-el 4*25*
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Tabe 4.$. Perhitungan Vou#e Air ang (ei#as )an 'u#ah Su#ur *esaan
NoDaerah Tata
=una Lahan
Luas
Lahan !A%
Durasi
Hujan
&fe"tif
!t0%
h
!#%) !#%
A
su#ur
Vou#e
Air ang
(eresa
!Vrs%C
Vou#e
Air ang
(ei#as
!Vab%
H tota
'u#ah
Su#ur
!n%
#$ ja# #$ #/ #/ # buah
1 Peru&ahan 1 1#27*61 *72 1*" 1*1 5*445 *"1 *641 5*!5" 6*15# 5
2 Peru&ahan 2 "#1*5! *72 1*" 1*1 5*445 *"1 *64" #*415 #*#! !" Peru&ahan " "4!7*!5 *72 1*" 1*1 5*445 *"1 *645 1*667 11*227 #
4 Peru&ahan 4 "4#*# *72 1*" 1*1 5*445 *"1 *646 1*67! 11*2"# #
5 Peru&ahan 5 "51#*77 *72 1*" 1*1 5*445 *"1 *64! 1*!5 11*"72 #
6 Peru&ahan 6 2"27*4 *72 1*" 1*1 5*445 *"1 *657 7*247 7*626 6
7 Peru&ahan 7 1754*1 *72 1*" 1*1 5*445 *"1 *62! 5*21# 5*4#1 4
! Peru&ahan ! !77*#1 *72 1*" 1*1 5*445 *"1 *67! 2*!1# 2*#64 2
# Peru&ahan # 22#5*!6 *72 1*" 1*1 5*445 *"1 *645 7*12 7*"7# 6
1 Peru&ahan 1 76*! *72 1*" 1*1 5*445 *"1 *625 2*251 2*"67 2
11 Peru&ahan 11 21"*27 *72 1*" 1*1 5*445 *"1 *651 6*27 6*5"1 5
12 Peru&ahan 12 1652*!# *72 1*" 1*1 5*445 *"1 *654 5*12" 5*"# 4
1" asa 1 #1*4 *72 1*" 1*1 5*445 *"1 *62" 2*6!7 2*!26 2
14 asa 2 1""7*2! *72 1*" 1*1 5*445 *"1 *721 4*567 4*!5 4
Sumber: Hasil perhitungan
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4.4.7. =a#bar Peren0anaan Su#ur *esaan
4.. Perhitungan Peren0anaan Sauran Drainase Persaahan
4..1. S"e#a Sauran Drainase a)a Daerah ang Diren0ana"an
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ambar !encana saluran rencana dapat dilihat pada lampiran
4..$. Data3Data Te"nis
+ata'data ang diperlukan dala& perhitungan drainase &odul adalah
se-agai -erikut: / n ( " harian ) = 1"5 &&hari / (ke-utuhan air irigasi) = 1 ltrdtha
= !,64 &&hari 3o = ",5 &&hari P = 1,5 &&hari $n = 6 && Luas Petak $aFah otal = " ha = " &2
4../. Perhitungan Drainase (o)u
Menghitung -esarna de-it drainase dengan &enggunakan ru&us se-agai
-erikut:
(+n) = (/n) 9 (n 8 (/ ' 3o ' P)) H $n
= 1"5 9 (1 8 (!,64 H ",5 H 1,5)) H 6
= 7!,64 &&hari
+& = (+n) (n 8 !,64)
= 7!,64 (1 8 !,64)
= #,12 ltdtha
Luas lahan se-esar " ha (" &2) sehingga de-it drainase ang harus
di-uang se-esar ,6! &"dt*
4..4. Di#ensi Sauran
+ari perhitungan drainase &odul didapatkan data de-it ang harus
di-uang untuk &asing'&asing saluran se-agai -erikut:
$aluran +rainase ersier 1 = ,1 &"dt
$aluran +rainase ersier 2 = ,6! &"dt
$aluran +rainase ersier " = ,6! &"
dt$aluran +rainase ersier 4 = ,1 &"dt
$aluran +rainase $ekunder 1 = ,6# &"dt
$aluran +rainase $ekunder 2 = ,1"7 &"dt
$aluran +rainase Pri&er = ,1"! &"dt
$elanjutna data de-it di atas digunakan untuk &eren%anakan di&ensi
&asing'&asing saluran, &ulai saluran drainase tersier sa&pai saluran drainase
pri&er ang &enuju sungai*
Contoh Perhitungan Di#ensi Sauran Drainase Tersier 1
1* Men%ari - dan h
0 =(i&in
)
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= ,4 &2
0 = - * h
,4 = h * h ,4 = h2
h = ,65 &
- = h = ,65 &
2* Men%ari nilai R
P = - 9 2h
= h 92h
= "h
= ,1#6 &
/ = P
$=
1#6,
,4= ,22 &
R = 21
"
21
S !n×
= 21
"
2
)#7,()22,(25,
1×
R = ,"7 &dt
"* Men%ari nilai NhitungNhitung = 0 * R
= ,4 * ,"7= ,1 &"dt
r = )("!4,65,
"!4,
* subkritis
h g
( ==
4* inggi jagaan
F =
= 1" 8 ,65
= ,22 &
Perhitungan selanjutna dapat dilihat pada ta-el -erikut*
-
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Tabe 4.$. Perhitungan Di#ensi Sauran Drainase Persaahan
Tana Lining
ode $aluran
N
ren%ana -h n sh - F 0 P / R r N hitung
(&"dt) (&) (&) (&) (&2) (&) (&) (&dt) (&"dt)
1 2 " 4 5 6 7 ! # 1 11 12 1"
$aluran +rainase ersier 1 *1 1* *25 *#7 *65 *65 *22 *4 *1#6 *22 *"7 *"!4 *1$aluran +rainase ersier 2 *6! 1* *25 *#7 *2!7 *2!7 *#6 *!" *!62 *#6 *!25 *4#1 *6!
$aluran +rainase ersier " *6! 1* *25 *#7 *2!7 *2!7 *#6 *!" *!62 *#6 *!25 *4#1 *6!
$aluran +rainase ersier 4 *1 1* *25 *#7 *66 *66 *22 *4 *1#7 *22 *"! *"!4 *1
$aluran +rainase
$ekunder 1*6# 1* *25 *147 *26! *26! *!# *72 *!" *!#
*#6! *5#!*6#
$aluran +rainase
$ekunder 2*1"7 1* *25 *147 *"45 *"45 *115 *11# 1*"6 *115
1*14! *624*1"7
$aluran +rainase Pri&er *1"! 1* *25 *147 *"46 *"46 *115 *12 1*"# *115 1*15 *624 *1"!
Sumber: Hasil perhitungan
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4... =a#bar Peren0anaan Drainase Persaahan