Definition

1. Noun:
   • A channel for excess water: A constructed passage or channel designed to carry surplus water safely over, around, or through a dam, weir, or other barrier to prevent overtopping and potential failure.

Usage Examples

• Noun:
  • Engineers designed a new spillway to handle the increased floodwaters.
  • During the heavy rains, water began to flow over the dam's main spillway.
  • The reservoir's emergency spillway was activated for the first time in decades.

Advanced Usage

• "Auxiliary spillway": A secondary, often less robust, spillway used only during extreme flood events when the primary spillway's capacity is exceeded.

  • The auxiliary spillway, made of grass and soil, was only intended for rare, catastrophic floods.

• "Service spillway": The primary, regularly used channel for releasing normal flows or managing reservoir levels.

  • The service spillway's gates are operated daily to control the river's flow downstream.

Variants and Related Words

• Spill (verb): To cause or allow liquid to flow over the edge of its container. (Note: This is the root verb from which "spillway" is derived, but it is a separate word with a broader meaning).
• Weir (noun): A low dam built across a river to raise the water level or divert its flow, often incorporating a spillway section.
• Floodway (noun): An artificial channel for diverting floodwater, similar in function to a spillway but often in a different context (e.g., around a city).

Synonyms

• Overflow channel: A direct descriptive synonym.
• Wasteweir: A term used for a spillway, especially one from a canal or levee.
• Bywash: A channel for carrying away surplus water.

Related Phrases (Not Phrasal Verbs)

• Spillway capacity: The maximum flow rate a spillway can safely discharge.

  • The dam's safety was reassessed after concerns about its spillway capacity.

• Spillway crest: The top of the spillway structure over which water begins to flow.

  • The water level rose just to the spillway crest before receding.

Related Idioms

(Note: "Spillway" is a technical term and is not commonly used in idiomatic expressions. The related verb "spill" is used in idioms.) - Spill the beans: To reveal a secret (uses the root verb "spill," not the noun "spillway"). - He finally spilled the beans about the surprise party.

Noun

1. a channel that carries excess water over or around a dam or other obstruction