1. INTRODUCTION - India Environment Portal

outer slope of 1:3 protected with filter mat and armour stone for the scour
protection due to the river flow is planned inside the creek (Figure 2.2).
The containment dike will be used for confining dredge material and interfaced
with property line of the plant neighboring the existing village.
2.2 DREDGING DETAILS
Approach channel: An approach channel of 12.98 kilometres to the berth is
proposed with the minimum depth of 21 m below CD so as to accommodate
berthing of 170,000 DWT vessels. From the preliminary soil investigation, the
dredged materials at this area are supposed to be mainly silty clay due to the fine
sediment deposit. Therefore, it is planned that the whole dredged materials have
to be disposed in deep water having depth beyond 22 m below CD.
Raw material berth: The raw material berthing area between the wharf and the
side edge of the inner channel will be dredged to 20 m below CD to allow berthing
of 170,000 DWT vessels.
Product berth: The product and future berthing area will be dredged to 12 m below
CD to allow berthing of 30,000 DWT vessels whereas water depth for 50,000
DWT vessels should be 13.5 m. To the extent possible, the dredged material will
be used for reclaiming the marshy land required for the port and form a site for the
steel plant.
Dredging volume: Based on the available hydrographic data and considering the
following, the capital dredging volume is estimated and given in Table 2.2.
• Side slope of 1:3 for the approach channels, turning basin and berthing basins
• Vertical tolerance of 0.9 m and horizontal tolerance of 5.5 m in both directions
for channels and basins where 20 m water depth are required
• Vertical tolerance of 0.7 m and horizontal tolerance of 4.7 m in both directions
for channels and basins where 20 m water depth are required
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