Dalsá is a rain fed river and has its source on Flateyjardalsheiði and flows north of Flateyjardalur into Skjálfandi. It is an enjoyable but rather small river where almost exclusively sea char are caught. Four rods are permitted to fish at a time. There are three fishing beats and two of them are fished at a time while one is rested. Sometimes salmon are caught, but they are not the main target.