Despite the extent of works done on modelling port water collisions, not much research effort has been devoted to modelling collisions at port anchorages. This paper aims to fill this important gap in the literature by applying the Navigation Traffic Conflict Technique (NTCT) to measuring the collision potentials in anchorages and for examining the factors contributing to collisions. Building on the principles of the NTCT, a collision potential measurement model and a collision potential prediction model were developed. These models were illustrated by using vessel movement data of the anchorages in Singapore port waters. Results showed that the measured collision potentials are in close agreement with those perceived by harbour pilots. Higher collision potentials were found in anchorages attached to the shoreline and international fairways, but not at those attached to confined water. Higher operating speeds, larger numbers of isolated danger marks and day conditions were associated with reduction in the collision potentials.

Navigational safety analysis relying on collision statistics is often hampered because of the low number of observations. A promising alternative approach that overcomes this problem is proposed in this paper. By analyzing critical vessel interactions this approach proactively measures collision risk in port waters. The proposed method is illustrated for quantitative measurement of collision risks in Singapore port fairways, and validated by examining correlations between the measured risks with those perceived by pilots. This method is an ethically appealing alternative to the collision-based analysis for fast, reliable and effective safety assessment, thus possessing great potential for managing collision risks in port waters.

Many researchers have studied vessel systems to enhance navigation safety at sea, or analysed the statistics of marine casualties of different flagged vessels as well as the fatalities and injuries in ferry accidents. However, little research has been devoted to port safety and especially navigation safety within Taiwanese territorial waters where over a 10-year period there have been 3428 marine accidents with 548 deaths and 524 vessels sunk. In this paper, we use the Grey Relational Analysis (GRA) to analyse the marine accident records of each of Taiwan's commercial ports from 1992–2003. Then, after interviewing the port authority managers and marine specialists, we discover the concerns felt by these professionals about Taiwanese commercial ports. We provide suggestions to strengthen port navigation safety.