Evaluation of dredging efficiency indices of TSHDs deployed in a navigational channel leading to Haldia Dock Complex

ABSTRACT

The navigational channel leading to Haldia Dock Complex suffers heavy sedimentation causing gradual reduction of water depth and posing inconvenience for marine traffic movements. To overcome this problem, Kolkata Port Trust (KoPT) undertook a long-term maintenance dredging plan for the achievement of desirable navigable depths. Trailing Suction Hopper Dredgers (TSHD) of Dredging Corporation of India (DCI) have been selected for the maintenance dredging. An economic and efficient dredging plan with the introduction of Optimization Technique has been framed ensuring the achievement of targeted depths. This paper presents a new methodology to evaluate site specific dredging efficiency indices (DEI) of TSHDs. The overall dredging performances can be expressed well by the four parameters such as average amount of solid settled volume (SSV) taken out per month, average production per load, average production rate per day and average contact time per load. The combined effect of these parameters determines the DEI of a dredger. The computed DEI of a TSHD performed in a year can be improved for the next year by enhancing the deficient parametric values following modified daily dredging schedules. This dredging procedure minimizes the huge maintenance dredging cost without any constraints.

KEYWORDS:

• Dredging efficiency indices
• HDC
• KoPT
• SSV
• TSHD

Acknowledgments

The authors are thankful to the authorities of KoPT, HDC and DCI for their help, guidance and encouragement during preparation of the manuscript. The authors are also grateful to the Engineers of WAPCOS India Limited for their valuable service rendered onboard monitoring as well as onboard data collection of maintenance dredging in Hooghly Estuary.

Disclosure statement

No potential conflict of interest was reported by the authors.