Running Water

How does urbanization (paving, etc.) affect runoff and infiltration in a small, previously forested, drainage basin?

• Both runoff and infiltration decrease

• Runoff decreases while infiltration increases

• Both runoff and infiltration increase

• Infiltration decreases while runoff increases

Which of the following features characterize wide streams and valleys?

• Rapids and channel-bed potholes

• Waterfalls and entrenched meanders

• V-shaped valley cross-sections

• Natural levees and broad floodplains

Which one of the following statements is true concerning natural levees?

• Natural levees are formed where the coarsest sediments are deposited adjacent to the channel during floods

• Natural levees are depositional features that only form during times when stream discharge is low

• Natural levees are erosional features left behind when meander cutoff occurs

• Natural levees are flat terraces on both sides of a stream valley that represent former flood plains left behind by a downcutting stream

A dam and reservoir are constructed on a graded river. What will happen?

• Deposition upstream from the dam; channel downcutting below

• Channel downcutting upstream from the dam; deposition below

• Deposition both upstream and downstream from the dam

• Channel downcutting both upstream and downstream from the dam

The lowest base level for most streams is sea level.

• True

• False

Which of the following describes the total sediment load transported by a stream?

• Capacity

• Discharge

• Competence

• Hydro-load factor

What type of stream pattern develops only on growing mountains like volcanoes or where the land surface is tectonically doming upward?

• Dendritic

• Radial

• Rectangular

• Trellis

Which of the following factors do not influence stream turbulence and average velocity?

• Channel shape and bed roughness

• Dissolved load and water temperature above freezing

• Discharge and stream gradient

• Stream gradient and channel roughness

At the head of a delta, the major channel splits into smaller channels that follow different paths to the sea. These smaller channels are known as ________.

• Tributaries

• Gullies

• Rills

• Distributaries

Which of the following is not part of the hydrologic cycle?

• Water evaporating from a lake

• Water infiltrating into the soil and bedrock

• Calcium carbonate dissolving in soil water and groundwater

• Water moving into creeks and streams following a rainstorm