Giant Seawall Jakarta atau New Manhattan Jakarta Proyek Mercu

Dampak Reklamasidan
Pengerukan Terhadap Sirkulasi
Arus Laut, Sungai, Sedimentasi,
dan Kualitas Air
Reklamasi dan Pengerukan
Bisa Membahayakan Negara
Muslim Muin Ph.D.
Ocean Engineering Research Group (OERG)
Institut Teknologi Bandung
Personal Web www.muteknologi.musmuin.com
Muslim Muin Ph.D.
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Expertise
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20011 – 2012,Head of Ocean Engineering Research Group
2005 – 2011, Head of Ocean Engineering Program
2000 – 2004, Faculty member of Ocean Engineering Program
1998 – 1999, Visiting Research Professor in University of Rhode Island, USA
1994 – 1997, Faculty member of Ocean Engineering Program
1987 – 1993, Graduate Student, University of Rhode Island, USA.
Education :
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Marine Facility Design
Structural Dynamics
Ocean Hydrodynamics, Sediment Transport, and Water Quality Modeling
Place/Date of Birth : Padang, April 7, 1960.
Employer
: Institut Teknologi Bandung, 1986 - present
Position History :
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Ph.D. in Ocean Engineering, University of Rhode Island, USA, 1993.
M.Sc. in Ocean Engineering, University of Rhode Island, USA, 1988.
B.E. in Civil Engineering, Institut Teknologi Bandung, Indonesia, 1984.
Website : www.muteknologi.musmuin.com
MuTeknologi Software
3D Ocean Hydrodynamics, Sediment Transport, Water Quality Model in GIS
System
Non-Orthogonal Curvilinear Coordinate Technique
•MuSed3D
•MoTuM
•MuDrillCutting3D
•MuQual3D
•MuHeat3D
•MuTsunami
User (License)
Arus
Pergerakan Partikel Air Gelombang
Pendek
 Arus Laut Gelombang Panjang
 Arus Laut Global (Ocean Circulation)
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Conveyor Belt
Gulf Stream
Indonesia Through Flow (ITF)
dll
Pergerakan Partikel Gelombang
Air
Ocean Circulation
Ocean Conveyer Belt
Arus Laut Gelombang
Panjang
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Gaya (Forcing)
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Pasang Surut
Angin
Perbedaan Densitas
Sungai
Pergerakan Dasar Laut
Geometri
 Batimetri
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Dampak Perubahan Arus Laut
Akibat Reklamasi dan
Pengerukan
Perubahan Kualitas Air
 Sediment Transport (Erosi/Deposisi)
 Perubahan Garis Pantai
 Navigasi Pelayaran
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Dampak Reklamasi dan
Pengerukan di Gresik Jawa Timur
Pengerukan di Banten
Dampak Pengerukan di
Banten
Arus laut pada jalur pipa PGN
disekitar daerah pengerukan akan
meningkat.
 Erosi pada jalur pipa
 Pipa akan tergantung (Free Span)
 Pipa pecah
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Dampak dari Proteksi Trestle di
BP Tangguh Papua
Pergerakan
Sediment Halus
Deposisi
Sediment
Erosi
Littoral
Sediment
Runtuhnya Cliff di BPTangguh
akibat berkurang Sediment dari
Timur
Tumpukan Sedimen di Sebelah
Barat
Daerah Reklamasi di Jakarta
Apa yang terjadi pada saat Musim
Barat?
Akibat Reklamasi
Aliran air laut dari Barat terhalang,
muka air naik.
 Aliran sungai mengalami hambatan
 Daerah Pluit Banjir.
 Diperparah oleh penurunan muka
tanah (Land Subsidence)
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Mangrove di Papua
Mangrove Penting dalam Arus
Laut
High Tide
Low Tide
Mangrove Cell
Tidal Hydrodynamics Exchange
Mangrove
Arus laut di mulut muara sangat besar
akibat keluar-masuk air ke mangrove
 Mengabaikan mangrove, hasil model
akan tidak akurat
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Akibat Reklamasi Mangrove
Tidal Dynamics hilang -> Arus
Mengecil
 Sedimentasi
 Pendangkalan
 Akhir alur pelayaran dikeruk -> Mahal
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Sebelum Reklamasi, lakukan simulasi
Hidrodinamka Laut, Kualitas Air,
Sedimentasi, dan Perubahan Garis
Pantai
MODEL 3D
NON-ORTHOGONAL
BOUNDARY FITTED
Model Feature
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Semi-Implicit: Time Step is large, not limited
by gravity wave speed.
Sigma Stretching and Z-coordinate
One Equation Turbulence Closure Model
Density Induced Current
Prognostic Simulation (density and current
couple)
Integrated into GIS
Windows System
Non-Orthogonal Curvilinear Technique
Governing Equations in Spherical
Coordinates
Governing Equations Boundary Fitted Coordinate
Model Testing in 3D Idealized Channel
Model Testing Storm Surge
Application of 3D Boundary Fitted Model by ASA Inc.
(New York, Bay of Fundy, San Francisco Bay, Savannah River,
etc.)
Publication
Dilakukan dengan Menggunakan Konsep Keliru
REKLAMASI JAKARTA
Dampak Giant Seawall
Jakarta
Giant Water Pump
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Power = Q x r x g x H
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Q = Water Discharge
r = Water Density
g = Gravity
H = Head
H = 10 m (Elevation + Lost +
Efficiency)
 Maximum Discharge (2 years Return
Period) ~ 2500 m3/det
 Power = 245 MW
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Operational Cost Giant
Seawall
Discharge Averages 200 m3/det
 Electric Price per KwH Rp 1400
 Yearly Pump Electricity Cost Rp 241
Milyar (USD 24 Million)
 Water Treatment Cost per m3 Rp 1000
 Total Cost Water Treatment per Year
Rp 6 Triliun (USD 600 Million)
 Who will pay?.. 60 Thousand
Residence in new reclamation area??
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Water Quality in Giant
Seawall
Giant Seawall Jakarta is Closed System. Entrance for Tg Priok
is not sufficient. Giant Seawall is not Palm Island Project.
Stagnant Water. Poor Water Quality. Mangrove will die. High
Operational Cost
Reklamasi Teluk Jakarta
Dilakukan dengan konsep yang salah
 Mengabaikan Sirkulasi Air Laut, Kualitas
Air, dan Sedimentasi.
 Ongkos Operasi (Pompa dan Kualitas
Air) sangat tinggi -> Jakarta Bangkrut
 Jika GSW dibangun, Jakarta terancam
tenggelam.
 GSW bukan solusi untuk penurunan
muka tanah (Land Subsidence)
 Jangan Menutup Teluk Jakarta
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Land Subsidence in New
Orleans
Scientists have proposed several causes for subsidence
in New Orleans. These causes range from
 Natural ones, such as settling of coastal sediments
and movement of the Michoud fault
 Human ones such as draining wetlands, diverting
sediment-bearing floodwaters from the Mississippi
River, and pumping ground water.
http://earthobservatory.nasa.gov/IOTD/view.php?id=662
3
Kenapa Tidak?
Kesimpulan
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Reklamasi dan Pengerukan Bisa
Membahayakan Ekonomi Negara jika
mengabaikan dampak perubahan sirkulasi
arus laut.
Jika dilakukan dengan konsep yang salah
dan lokasi yang tidak tepat, bukan Lahan
Baru yang diperoleh tapi Persoalan Baru.
Sebelum Reklamasi atau Pengerukan, harus
dilakukan simulasi Model Hidrodinamika Tiga
Dimensi, Sedimen, Kualitas Air, dan
Perubahan Garis Pantai
Reklamasi dapat merubah aliran sungai dan
menyebabkan banjir di dataran rendah
Dampak Reklamasi daerah Mangrove sangat
besar