Tailwaters

Part of speech: noun

Definitions

1. The water that flows downstream just below a dam or weir ; the runoff that drains away from fields or land after rain or irrigation
2. Stream water released beneath a dam or spillway ; surplus water that runs off a field or landscape once rain or watering has ended
3. The current pouring out below a barrier such as a dam ; the drainage that leaves cultivated or sloping ground after precipitation or irrigation

Etymology: "Tailwaters" is the plural of "tailwater," a compound formed from "tail" and "water." The base word is straightforward: the tail of something, here the part at the rear or downstream end, joined to water. In practice the term names the water flowing away from the downstream side of a dam, weir or millrace, the stretch below the point where the water has been held back or channelled. Anglers and river managers use the plural to refer to several such stretches at once, since each dam or structure has its own tailwater.