ABSTRAK Suplai air bersih di Kota Tebing Tinggi dilayani oleh PDAM Tirta Bulian. Namun penambahan jumlah konsumen yang tidak diikuti dengan peningkatan kapasitas jaringan, penyediaan dan pelayanan air bersih, telah menimbulkan suatu kesulitan dimana air bersih yang tersedia tidak cukup bagi penduduk yang membutuhkannya. Metode penelitian yang digunakan adalah terlebih dahulu mengumpulkan data yang dibutuhkan baik primer dan sekunder. Kemudian menghitung banyaknya penduduk yang ada di area perumahan tersebut. Tahapan berikutnya adalah menghitung kebutuhan air pada tiap titik layanan pada area perumahan. Dari hasil perhitungan yang telah dilakukan, kemudian dilakukan analisa menggunakan metode Hardy Cross, setelah itu dilakukan perbandingan menggunakan analisis Program Epanet 2.0. Berdasarkan hasil perhitungan di dapat bahwa total kebutuhan air untuk Perumahan Grya Prima Tebing Tinggi adalah 330 m /hari. Dengan kebutuhan air pada jam puncak (peak hour) adalah 0,012963 m /detik. Pipa yang dipakai adalah jenis pipa galvanized iron dengan diameter 75 mm dan 50 mm. Dari penelitian ini disimpulkan bahwa perhitungan manual dengan menggunakan metode Hardy Cross dianggap dapat mendekati analisis program Epanet 2.0, setelah dilakukan perbandingan hasil analisa metode hardy-cross dengan analisis program Epanet 2.0.
Kata Kunci : Kebutuhan Air, Diameter Pipa, Hardy Cross, Epanet 2.0.
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DAFTAR ISI Halaman KATA PENGANTAR……………………………………………….………........ i ABSTRAK………………………………………………………………… ……... iii DAFTAR ISI……………………………………………………………………… iv DAFTAR GAMBAR............................................................................................... ix DAFTAR TABEL.................................................................................................... xii DAFTAR NOTASI.................................................................................................. xiii DAFTAR LAMPIRAN........................................................................................... xiv BAB I PENDAHULUAN 1.1. Latar Belakang ..........................................................................................1 1.2. Maksud dan Tujuan................................................................................... 2 1.3. Ruang Lingkup Pembahasan .................................................................... 2 1.4. Perumusan Masalah...................................................................................3 1.5. Pembatasan Masalah................................................................................. 3 1.6. Metodologi Penelitian............................................................................... 5 1.7. Sistematika Penulisan................................................................................6
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BAB II TINJAUAN PUSTAKA 2.1. Sistem Distribusi Air Bersih..................................……………………... 8 2.1.1. Penampungan Air Reservoir................................................................ 8 2.1.2. Sistem Perpipaan..................................................................................9 2.2. Sistem Penyediaan Air Bersih................................................................... 10 2.3. Studi Kebutuhan Air Bersih...................................................................... 12 2.3.1 Kebutuhan Domestik.............................................................................15 2.3.2 Kebutuhan Non Domestik.....................................................................15 2.3.3 Fluktuasi Kebutuhan Air....................................................................... 18 2.3.4 Kehilangan Air...................................................................................... 19 2.4. Konsep Dasar Aliran Fluida...................................................................... 20 2.5.Kehilangan Tinggi Tekanan....................................................................... 21 2.5.1 Kehilangan Tinggi Tekanan Mayor (Mayor Losses)........................... 21 2.5.1.1 Persamaan Hazen Williams...........................................................21 2.5.1.2 Persamaan Darcy Weisbach.......................................................... 22 2.5.2 Kehilangan Tinggi Tekan Minor (Minor Losses)................................. 26 2.6. Jenis Jaringan Pemipaan............................................................................27 2.6.1 Sistem Jaringan Pemipaan Seri........................................................
27
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2.6.2. Sistem Jaringan Pemipaan Bercabang (Branch) .............................
28
2.6.3. Sistem Jaringan Pemipaan Tertutup (Loop) ..................................
28
2.6.4. Sistem Jaringan Pemipaan Kombinasi................................................. 29 2.7. Analisis Jaringan Pipa dengan Metode Hardy Cross............................... 29 2.8. Pengenalan EPANET............................................................................... 34 2.8.1 Kemampuan model hidrolis. ............................................................... 35 2.8.2 Kemampuan Model Kualitas air........................................................... 36 BAB III GAMBARAN UMUM LOKASI STUDI 3.1. Letak dan Batas Administratif...................................................................39 3.2. Perusahaan Daerah Air Minum (PDAM) Tirta Bulian..............................42 3.2.1. Sejarah Singkat PDAM Tirta Bulian.................................................. 41 3.2.2. Kriteria Penggolongan Tarif Air Minum PDAM Tirta Bulian Tebing Tinggi.....................................................................................43 3.2.3 Booster Pump PDAM Tirta Bulian......................................................47 BAB IV METODOLOGI PENELITIAN 4.1. Pengumpulan Data ....................................................................................50 4.2. Analisa Data.............................................................................................. 51 BAB V ANALISA DAN PEMBAHASAN 5.1. Jumlah Pemakaian Air...............................................................................54 vi
5.1.1 Kebutuhan Air bersih Golongan Non Niaga dan Niaga...................... 54 5.1.2 Kebutuhan Air Bersih Golongan Sosial...............................................54 5.1.2.1. Golongan Sosial Umum............................................................... 54 5.1.2.1. Golongan Sosial Khusus ............................................................. 55 5.2. Estimasi Pemakaian Air Pada saat beban puncak (peak hour)..................56 5.3. Karakteristik Pipa ..................................................................................... 61 5.4.Analisa Perhitungan dengan Metode Hardy-Cross....................................63 5.5. Analisis jaringan dengan Program EPANET 2.0...................................... 83 5.5.1 Tahapan menggunakan Epanet 2.0...................................................... 83 5.5.2 Masukan Data (Input).......................................................................... 83 5.5.3 Proses Ekesekusi Program................................................................... 89 5.5.4 Keluaran Data (Output) .................................................................... 89 5.6. Perbandingan metode Hardy Cross dan analisis Program Epanet 2.0….. 91 5.6.1. Perbandingan debit .....................................................................
91
5.6.2. Perbandingan Headloss (Kehilangan Energi)……………..……..... 93 5.7. Perbandingan Analisa Program Epanet 2.0 dengan kondisi di lapangan.. 95 BAB VI KESIMPULAN DAN SARAN 6.1. Kesimpulan................................................................................................97
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6.2. Saran ......................................................................................................... 98 DAFTAR PUSTAKA LAMPIRAN
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DAFTAR GAMBAR Gambar 1.1
Skema Jaringan Pipa yang akan dianalisa......................................... 4
Gambar 2.1
Check Valve ………………………………………..………………9
Gambar 2.2
Gate Valve………………………………………………………... 10
Gambar 2.3
Kaitan hubungan antara unsur-unsur fungsional dari suatu Sistem penyediaan air kota................................................................ 11
Gambar 2.4
Diagram Moody................................................................................. 23
Gambar 2.5
Pipa Jaringan Seri ............................................................................. 28
Gambar 2.6
Pipa Jaringan Bercabang....................................................................28
Gambar 2.7
Pipa Jaringan Tertutup (Loop)........................................................... 29
Gambar 2.8
Pipa Jaringan Kombinasi .................................................................. 29
Gambar 2.9
Sistem Jaringan Pipa.......................................................................... 30
Gambar 2.10 Tampilan EPANET............................................................................37 Gambar 3.1
Peta Kelurahan di Kota Tebing Tinggi.............................................. 40
Gambar 3.2
Kompleks Perumahan Grya Prima ....................................................41
Gambar 3.3
Reservoir di Booster Pump PDAM Tirta Bulian............................... 47
Gambar 3.4
Pompa Sentrifugal di Booster Pump PDAM Tirta Bulian.................48
Gambar 4.1
Diagram Alir Metodologi Penelitian................................................. 49
Gambar 4.2
Diagram alir Analisa Menggunakan Epanet 2.0................................ 53
Gambar 5.1
Grafik Estimasi pemakaian air per hari............................................. 59
Gambar 5.2
Pembagian debit Aliran awal masing-masing pipa (Qo)............
Gambar 5.3
Loop I.................................................................................................67
Gambar 5.4
Loop II............................................................................................... 67
Gambar 5.5
Loop III.............................................................................................. 68
64
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Gambar 5.6
Loop IV..............................................................................................69
Gambar 5.7
Loop V............................................................................................... 69
Gambar 5.8
Loop VI..............................................................................................70
Gambar 5.9
Loop VII.............................................................................................71
Gambar 5.10 Loop VIII........................................................................................... 71 Gambar 5.11 Loop IX..............................................................................................72 Gambar 5.12
Loop X ............................................................................................. 73
Gambar 5.13 Loop XI .............................................................................................73 Gambar 5.14 Loop XII ............................................................................................74 Gambar 5.15 Loop XIII .......................................................................................... 75 Gambar 5.16 Loop XIV........................................................................................... .75 Gambar 5.17 Loop XV............................................................................................ 76 Gambar 5.18 Loop XVI........................................................................................... 77 Gambar 5.19 Loop XVII..........................................................................................78 Gambar 5.20 Loop XVIII........................................................................................ 78 Gambar 5.21 Tampilan Map Dimensions................................................................84 Gambar 5.22 Tampilan Map Options ..................................................................... 84 Gambar 5.23 Tampilan Defaults .............................................................................85 Gambar 5.24 Latar belakang peta ........................................................................... 86 Gambar 5.25 Tampilan Reservoir ...........................................................................87 Gambar 5.26 Tampilan Junction..............................................................................87 Gambar 5.27 Tampilan Pipa.................................................................................... 88 Gambar 5.28 Visualisasi Jaringan distribusi............................................................89
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DAFTAR TABEL Tabel 2.1
Unsur-unsur fungsional dari sistem penyediaan air minum.............. 12
Tabel 2.2
Konsumsi Air Bersih......................................................................... 15
Tabel 2.3
Rata-rata Kebutuhan Air Per Orang Per Hari.................................... 16
Tabel 2.4
Koefisien Hazen-Williams................................................................. 22
Tabel 2.5
Jenis aliran berdasarkan niai Bilangan Reynold, R........................... 25
Tabel 2.6
Nilai untuk koefisien colebrook...................................................... 25
Tabel 2.7
Kehilangan tinggi tekanan pada katup, alat penyesuaian dan pipa yang digunakan.................................................................................. 27
Tabel 2.8
Harga K untuk pipa ......................................................................... 32
Tabel 2.9
Perhitungan Hardy Cross ..................................................................33
Tabel 3.1
Tarif Air Minum PDAM Tirta Bulian Tebing Tinggi....................... 46
Tabel 4.1
Perhitungan Hardy-Cross.................................................................. 52
Tabel 5.1
Pressure Gauge yang terbaca selama 24 jam .................................... 56
Tabel 5.2
Estimasi pemakaian per hari ............................................................. 56
Tabel 5.3
Pemakaian air Periode I 06.00 – 08.00 ............................................. 57
Tabel 5.4
Pemakaian air Periode II 09.00 – 11.00 ............................................57
Tabel 5.5
Pemakaian air Periode III 12.00 – 15.00 ...........................................57
Tabel 5.6
Pemakaian air Periode IV 16.00 – 19.00 .......................................... 58
Tabel 5.7
Pemakaian air Periode V 20.00 – 24.00 ............................................58
Tabel 5.8
Pemakaian air Periode IV 01.00 – 05.00 .......................................... 58
Tabel 5.9
Total Pemakaian air selama 24 jam .................................................. 59
Tabel 5.10
Data Pipa............................................................................................61
Tabel 5.11
Loop I.................................................................................................67
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Tabel 5.12
Loop II............................................................................................... 68
Tabel 5.13
Loop III.............................................................................................. 68
Tabel 5.14
Loop IV..............................................................................................69
Tabel 5.15
Loop V .............................................................................................. 70
Tabel 5.16
Loop VI .............................................................................................70
Tabel 5.17
Loop VII............................................................................................ 71
Tabel 5.18
Loop VIII........................................................................................... 72
Tabel 5.19
Loop IX..............................................................................................72
Tabel 5.20
Loop X............................................................................................... 73
Tabel 5.21
Loop XI..............................................................................................74
Tabel 5.22
Loop XII.............................................................................................74
Tabel 5.23
Loop XIII........................................................................................... 75
Tabel 5.24
Loop XIV........................................................................................... 76
Tabel 5.25
Loop XV............................................................................................ 76
Tabel 5.26
Loop XVI........................................................................................... 77
Tabel 5.27
Loop XVII......................................................................................... 78
Tabel 5.28
Loop XVIII........................................................................................ 79
Tabel 5.29
Faktor koreksi iterasi I……………………………………………..`79
Tabel 5.30
Faktor koreksi iterasi V……………………………………………. 80
Tabel 5.31
Besar debit akhir aliran dan Headloss untuk tiap pipa...............
Tabel 5.32
Nilai Flow,Velocity,Headloss dan Friction Factor EPANET……... 90
Tabel 5.33
Selisih debit masing- masing pipa ..............................................
Tabel 5.34
Selisih headloss masing - masing pipa…………………….............. 95
81
92
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DAFTAR NOTASI A
= luas penampang aliran (m )
C
= koefisien kekasaran pipa Hazen – William
d
= diameter pipa (m)
f
= Faktor Gesekan
g
= percepatan gravitasi
hf
= kerugian gesekan dalam pipa (m)
K
= koefisien kerugian pada pipa
L
= panjang pipa (m)
LPS = Liter per second (detik). Q Q
= Debit aliran dalam pipa (m /detik). = Pemakaian air rata-rata sehari (m )
Qe
= Debit aliran menggunakan Epanet 2.0
Qh
= Debit aliran menggunakan metode Hardy Cross.
Re
= Bilangan Reynold
S
= Kemiringan Hidrolis (m)
T
= Jangka waktu pemakaian (jam)
v
= kecepatan aliran ( m/s )
∆Q
= koreksi aliran
= koefisien colebrook
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DAFTAR LAMPIRAN Lampiran I
: Peta Jangkauan Jaringan Pipa PDAM Tirta Bulian Tebing Tinggi
Lampiran II
: Laporan Sentral InformasiRadio Handy Talky Tirta Bulian
Lampiran III : Pengumuman Nomor : 03/II/PDAM-TB/TT/2012 Tentang Penyesuaian tarif Air Minum PDAM TIRTA BULIAN TEBING TINGGI Lampiran IV :Daftar Rekening yang akan ditagih (DRD-A) Lampiran V
: Lanjutan Perhitungan Iterasi Metode Hardy-Cross
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