<li>Dams are usually installed between 10-20 m along the swale. They are distributed such that the crest of each dam is at approximately the same elevation as the toe of the upstream dam. If the slope along the swale varies, so should the distance between the dams.</li> | <li>Dams are usually installed between 10-20 m along the swale. They are distributed such that the crest of each dam is at approximately the same elevation as the toe of the upstream dam. If the slope along the swale varies, so should the distance between the dams.</li> |