Flashcards: River Hydrology and Flood Management — 24 cards

River drainage basin — definition?

Area where all water drains into a main river.

Watershed boundary — role?

Separates adjacent drainage basins.

Main river system — components?

Main river plus tributaries forming a network.

River course sections — types?

Upper, middle, lower courses.

River types — examples?

Glacier, rain, and mixed rivers.

Flow regime types — influence?

Determine seasonal water flow patterns.

Flow delay time — effect?

Shorter delay causes quicker runoff.

River gradient — what?

Vertical drop per kilometer.

Discharge — definition?

Volume of water passing a point per second.

Precipitation distribution — impact?

Affects flow regime and flood timing.

Urbanization — effect on runoff?

Reduces infiltration, increases runoff.

Tides — high water?

Spring tide causes higher water levels.

Tides — low water?

Neap tide causes lower water levels.

Dikes — purpose?

Prevent flooding during high water.

Floodplains — formation?

Deposited sediments raise floodplain levels.

River length profile — sections?

Upper, middle, lower courses.

Flow regime — in mixed rivers?

More uniform throughout the year.

Flow delay time — decreased by?

Urbanization and soil sealing.

Sedimentation — effect on floodplain?

Raises elevation, requiring higher dikes.

River gradient — in upper course?

Steep, high drop, rapid flow.

Discharge — varies with?

Precipitation and human activity.

Precipitation — affects?

Flow regime and flood risk.

Tide variations — influence?

Affect river levels and flood defenses.

Dikes — during spring tide?

High sea levels increase flood risk.