Excerpts from Japan International Coorporation Agency(JICA)

GENERAL INFORMATION

Port of Samarinda is located on Sungai Mahakam (East Kalimantan Province) about 39miles/75km upstream from the river mouth (00º 32’ 00” N, 107º 09’ 00” E). The entrance channel to the port is facing Makassar Strait from Mahakam Delta Access Channel width is 70m, depth =6m. Pilotage required for vessels over 150GRT. Vessels less than 153m length(LOA) and 6.8draft are allowed to enter the channel.

Our location (00º 34’ 00” S, 117º 11’ 10” E)  is located on the right bank of Mahakam river at about 13km in straight line to the southeast form the center of Samarinda City. As Palaran is on the opposite bank of Mahakam river to the center of Samarinda City, it is necessary to cross a bridge upstream of the river and it takes about 45minutes by vehicle. Most of the road from the center of Samarinda City to Palaran is paved except those in the city of the Project site. Some section of this road is now under the expansion work.

Our location is located on the flat land on the right bank of Mahakam River at about 50km upstream from the river mouth (about 15km downstream from Samarinda City). There is a hill of about 50m high at about 500m behind the bank line, and the road from Samarinda City leads from the rear side of the hill to Palaran.

Average rainfall is about 140mm per month all thru the year. The months with rainfall more than 200mm are Feb, Apr, May, Sep & July.

SOUNDING SURVEY DEC 2001

The sounding survey along Mahakam River and the channel was carried out using two different frequencies, which were 210kHz and 33kHz

The calculated value of Zo(the difference between Mean Sea Level & NLLW) by harmonic analysis is 1.1m

OUR LOCATION HWL/LWL

High Water Level = +2.65m
Low Water Level=0.0m

SUB-SOIL CONDITION

The layer from the ground surface to approximately -15m in depth (NLLW) consists of mainly soft silt/clay. However, the layer of more than -15m in depth (NLLW) up to supporting layer consists of mainly fine to medium sand

The layer that is clearly determined as the supporting layer with N-value of 50 or more consisting of clay lies at approximately -25m in depth (NLLW) at the center and downstream part of the proposed port site and at an approximately -41m in depth (NLLW) at the upstream part of the proposed port site

NLLW :nearly lowest low water

TIDE

Tidal range is 1.5m at Port of Samarinda, same as estuary. Low Water Spring -5.7m

Tidal current is experienced in the season from Sep to Dec with 2.5knot at ebb tide and 2knot at flood time. Average tidal range in Samarinda is 1.80m at spring tide and 0.5m at neap tide. The type of tidal form is mixed semi-diunal and semi-diurnal is rather dominant.

CURRENT

Relationship between prevailing current direction & tide: The prevailing current direction in dry season at Mahakam River and the channel was the same as the flow line of the Mahakam Ricer and channel. Prevailing current direction: 315degrees

Current velocity in dry season(Jul-Aug):

4.5m above river bed=2.5m/sec
1.5m above river bed=2.3m/sec

WAVE

The wave direction is nearly constant, mainly in the directions from S and partially in the waves from NE-E were seen. Maximum wave height was less than 0.4m and average wave height is 0.1m