This paper describes a new effective algorithm to estimate routing congestion and to resolve highly congested regions for a given detailed placement. The major features of the proposed technique can be summarized as follows. Firstly, if there are congested regions due to some nets which pass through the regions it can determine which cells affect those congested spots seriously and moves some of them to resolve congestion effectively. Secondly, since the proposed technique uses the ripple movement technique to move cells it resolves congestion without sacrificing wire length. Thirdly, we use an efficient incremental data structure to trace the changes in congestion and wire length as cells move. Hence, selection of cells to move could be very accurate and fast in the course of iteration. Finally, although an MST net model is used to resolve congestion in this paper, proposed technique can be work with any net model. Particularly, if proposed technique can obtain routing information from a real router, congestion can be resolved more effectively. Experimental results show that the proposed technique can resolve congestion effectively and efficiently without sacrificing wire length.