Lake Herengawe is a small coastal dune lake situated west of Whanganui. The lake and its margins covers 33.5 hectares, of which almost 50% is open water (lacustrine wetland) with the remaining area being lowland swamp (palustrine).The lake is a dammed valley lake, formed from streams draining the consolidated dunes that have been blocked by moving sand. The site is highly modified with pasture to the edge in most places.
