[Objective] In China’s northern regions, winter ice accumulation in front of piers raises water levels and may obstruct downstream bridges, threatening transportation and railway infrastructure along the riverbanks. Currently, studies of backwater patterns and flow-field characteristics around skewed bridge piers under ice-drift conditions remain insufficient. This study aims to investigate the backwater characteristics and flow characteristics with varying skew angles under different ice flow mass fractions. [Methods] To simplify complex ice-water interactions, we modeled irregular ice blocks as spherical particles using the Lagrangian Discrete Phase Model (DPM) in simulations. Key forces such as virtual mass forces and pressure gradient forces were incorporated to improve model operability and computational efficiency. The developed three-dimensional two-way coupled turbulent numerical model, integrating the VOF multiphase flow model with the RNG k-ε turbulence model, was validated against flume-test data and accurately simulated ice-water two-phase flow. [Results] In ice-jammed rivers, increasing the number of bridge piers significantly enhanced vortex generation downstream, leading to more complex flow structures and more pronounced surface fluctuations. At a specific ice particle volume fraction, the maximum upstream backwater length progressively increased with increasing skew angle, reaching up to approximately 2.6 times the river width. At a fixed skew angle, both the length and height of upstream backwater increased with the volume fraction of ice particles. Ice particles affected water-surface height more strongly than backwater length. Among the piers, ice particles exerted the most significant impact on the ice jam length and height in front of Pier 1, while the effect on the tail pier was minimal. Nearshore and inter-pier flow velocities gradually increased, vortex zones expanded, and scouring effects on the shoreline intensified. Additionally, both ice jam length and height showed a positive correlation with water depth. Their spatial distribution was governed by pier interference mechanisms, exhibiting a distinct gradient and nonuniform distribution. Increased water depth significantly elevated nearshore and inter-pier velocities, interacting with ice jams and ice particles to intensify flow complexity downstream. As a key parameter regulating Froude number, flow capacity, and ice accumulation morphology, water depth profoundly influenced both ice jam formation and flow-around characteristics. [Conclusions] In ice-jammed channels, pronounced hydraulic interactions existed between skewly aligned bridge piers, causing slight wake deflection. The resulting backwater effect varied non-monotonically, significantly redistributing and partitioning the channel flow to form multi-peak velocity distributions. In bridge design for ice-jam-prone rivers, skew angles of 50°-60° should be avoided to ensure adequate flow guidance. While maintaining structural stability, smaller design parameters were recommended, coupled with enhanced ice-deflection measures for the first pier, to mitigate ice-jam flood risks and improve overall bridge safety.