Highwater Field

Datum — listed here as Highwater Field — reports what the ground under you does: how far you are above the river or the sea, what the slope above you has done before, and what to watch for with your own eyes. It works with no signal, once you download the region you are going to. It will never send you a warning. It has no sensors and receives nothing. Silence from this app means nothing at all. Download before you travel, on wifi. In the valley it is too late. WHAT IT SHOWS • Your height above the river or the sea, and whether that height was surveyed or estimated — the app always says which. • A cross-section of the ground where you are standing, with the level past events reached, drawn solid where surveyed and dashed where estimated. • All six hazards for the region — flooding, landslides, avalanches, ground shaking, tsunami, lahars — including the ones with nothing recorded, shown…