Time between peak rainfall and peak discharge is known as what?

Time between peak rainfall and peak discharge is known as what?

• A. Peak Discharge
• B. Base Flow
• C. Delta
• D. Lag Time

Answer: (D)

Lag time is the delay between the moment rainfall reaches its peak and the river’s discharge reaches its peak. Water from the rainfall has to move through the drainage basin—some infiltrates the soil and recharges groundwater, some runs off the surface, and it all travels through streams to the main channel. Because of these storage and travel processes, the discharge peak occurs after a delay. The length of this lag depends on how quickly water can move through the basin: large basins with more storage and slower movement lengthen lag time, while steep or urbanized basins with rapid runoff shorten it. For contrast, peak discharge is the highest flow rate reached, base flow is the normal groundwater-supported flow, and a delta is a landform at the river’s mouth.

Lag time is the delay between the moment rainfall reaches its peak and the river’s discharge reaches its peak. Water from the rainfall has to move through the drainage basin—some infiltrates the soil and recharges groundwater, some runs off the surface, and it all travels through streams to the main channel. Because of these storage and travel processes, the discharge peak occurs after a delay. The length of this lag depends on how quickly water can move through the basin: large basins with more storage and slower movement lengthen lag time, while steep or urbanized basins with rapid runoff shorten it. For contrast, peak discharge is the highest flow rate reached, base flow is the normal groundwater-supported flow, and a delta is a landform at the river’s mouth.