Hydrograph Flashcard

Front

What is a hydrograph?

Back

A hydrograph is a graphical representation of the flow of water in a river or stream over time, showing how discharge changes in response to rainfall or snowmelt.

Front

What does the peak discharge on a hydrograph indicate?

Back

The peak discharge indicates the maximum flow rate of water in the river or stream during a specific event, such as a storm.

Front

What factors influence the shape of a hydrograph?

Back

Factors include rainfall intensity and duration, drainage basin characteristics (size, shape, land use), and soil saturation levels.

Front

What is the difference between a flashy and subdued hydrograph?

Back

A flashy hydrograph shows rapid increases and decreases in discharge, often due to steep slopes and urbanization, while a subdued hydrograph has a more gradual rise and fall, typical of flat or forested areas.

Front

How does land use affect hydrograph shape?

Back

Urban areas with impervious surfaces lead to quicker runoff and a flashy hydrograph, while forested areas absorb more water, resulting in a subdued hydrograph.

Front

What is the significance of the lag time in a hydrograph?

Back

Lag time is the delay between the peak rainfall and peak discharge, indicating how quickly water travels through the drainage basin.

Front

What does a steep rising limb on a hydrograph indicate?

Back

A steep rising limb indicates rapid runoff, often due to heavy rainfall or a steep drainage basin.

Front

What is base flow in a hydrograph?

Back

Base flow is the normal level of discharge in a river or stream, maintained by groundwater contributions.

Front

How can hydrographs be used in flood management?

Back

Hydrographs help predict flood events by analyzing past discharge patterns, allowing for better planning and response strategies.

Front

What is the role of vegetation in a drainage basin's hydrograph?

Back

Vegetation helps to slow down runoff, increase infiltration, and reduce peak discharge, leading to a more subdued hydrograph.