A method for reducing reductant deposits in an exhaust conduit fluidly coupled to an engine comprises operating the engine to produce an exhaust gas. The exhaust gas is communicated into the exhaust conduit which has an initial cross-sectional area. An initial flow rate corresponding to an initial flow velocity of the exhaust gas entering the exhaust conduit is determined. The initial flow rate and, thereby the initial flow velocity of the exhaust gas, increases or decreases based on an operating condition of the engine. The initial flow rate of the exhaust gas is compared with a predetermined threshold. If the initial flow rate of the exhaust gas is lower than the predetermined threshold, a cross-sectional area of the exhaust conduit is reduced. The reducing of the cross-sectional area causes the exhaust gas to have an adjusted flow velocity greater than the initial flow velocity.