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. Expertise :

◦ 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 :

◦ 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 :◦ 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 Software3D Ocean Hydrodynamics, Sediment Transport, Water Quality Model in GIS SystemNon-Orthogonal Curvilinear Coordinate Technique

•MuSed3D•MoTuM•MuDrillCutting3D•MuQual3D•MuHeat3D•MuTsunami

User (License)

ArusPergerakan Partikel Air

Gelombang PendekArus Laut Gelombang PanjangArus Laut Global (Ocean

Circulation)◦Conveyor Belt◦Gulf Stream◦Indonesia Through Flow (ITF)◦dll

Pergerakan Partikel Gelombang Air

Ocean Circulation

Ocean Conveyer Belt

Arus Laut Gelombang PanjangGaya (Forcing)

◦Pasang Surut◦Angin◦Perbedaan Densitas◦Sungai◦Pergerakan Dasar Laut

GeometriBatimetri

Dampak Perubahan Arus Laut Akibat Reklamasi dan PengerukanPerubahan Kualitas AirSediment Transport

(Erosi/Deposisi)Perubahan Garis PantaiNavigasi Pelayaran

Dampak Reklamasi dan Pengerukan di Gresik Jawa Timur

Pengerukan di Banten

Dampak Pengerukan di BantenArus laut pada jalur pipa PGN

disekitar daerah pengerukan akan meningkat.

Erosi pada jalur pipaPipa akan tergantung (Free Span)Pipa pecah

Dampak dari Proteksi Trestle di BP Tangguh Papua

Deposisi Sediment

ErosiLittoral Sediment

Pergerakan Sediment Halus

Runtuhnya Cliff di BPTangguh akibat berkurang Sediment dari Timur

Tumpukan Sedimen di Sebelah Barat

Daerah Reklamasi di JakartaApa yang terjadi pada saat Musim Barat?

Akibat ReklamasiAliran air laut dari Barat

terhalang, muka air naik.Aliran sungai mengalami

hambatanDaerah Pluit Banjir.Diperparah oleh penurunan muka

tanah (Land Subsidence)

Mangrove di Papua

Mangrove Penting dalam Arus Laut

High Tide

Low Tide

Mangrove Cell

Tidal Hydrodynamics Exchange MangroveArus laut di mulut muara sangat

besar akibat keluar-masuk air ke mangrove

Mengabaikan mangrove, hasil model akan tidak akurat

Akibat Reklamasi MangroveTidal Dynamics hilang -> Arus

MengecilSedimentasiPendangkalanAkhir alur pelayaran dikeruk ->

Mahal

MODEL 3DNON-ORTHOGONAL BOUNDARY FITTED

Sebelum Reklamasi, lakukan simulasi Hidrodinamka Laut, Kualitas Air, Sedimentasi, dan Perubahan Garis Pantai

Model FeatureSemi-Implicit: Time Step is large, not

limited by gravity wave speed.Sigma Stretching and Z-coordinateOne Equation Turbulence Closure

ModelDensity Induced CurrentPrognostic Simulation (density and

current couple)Integrated into GISWindows 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

REKLAMASI JAKARTADilakukan dengan Menggunakan Konsep Keliru

Dampak Giant Seawall Jakarta

Giant Water PumpPower = Q x r x g x H

◦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

Operational Cost Giant SeawallDischarge Averages 200 m3/detElectric Price per KwH Rp 1400Yearly Pump Electricity Cost Rp 241

Milyar (USD 24 Million)Water Treatment Cost per m3 Rp

1000Total Cost Water Treatment per Year

Rp 6 Triliun (USD 600 Million)Who will pay?.. 60 Thousand

Residence in new reclamation area??

Water Quality in Giant Seawall

Stagnant Water. Poor Water Quality. Mangrove will die. High Operational Cost

Giant Seawall Jakarta is Closed System. Entrance for Tg Priok is not sufficient. Giant Seawall is not Palm Island Project.

Reklamasi Teluk JakartaDilakukan dengan konsep yang salahMengabaikan Sirkulasi Air Laut,

Kualitas Air, dan Sedimentasi.Ongkos Operasi (Pompa dan Kualitas

Air) sangat tinggi -> Jakarta BangkrutJika GSW dibangun, Jakarta terancam

tenggelam.GSW bukan solusi untuk penurunan

muka tanah (Land Subsidence)Jangan Menutup Teluk Jakarta

Land Subsidence in New OrleansScientists 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 faultHuman 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=6623

Kenapa Tidak?

KesimpulanReklamasi 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