CFM CFM Hydrology & Hydraulics 2

Question 1

A watershed with impervious surfaces increased from 10% to 40% will generally experience what change in peak runoff?

Accepted Answer

Peak runoff increases due to reduced infiltration and faster response time

Answer

Peak runoff decreases due to increased infiltration

Answer

Peak runoff remains unchanged if detention is provided

Answer

Peak runoff increases only during 500-year events

Question 2

What is the primary purpose of a 'No-Rise Certification' in floodway encroachment analysis?

Accepted Answer

To demonstrate that proposed development will not increase the BFE in the floodway

Answer

To certify that a new structure will not sink into saturated soils

Answer

To confirm that a FIRM revision is not needed

Answer

To certify that a property is naturally above the BFE

Question 3

Which of the following best describes 'effective hydraulic connectivity' in floodplain management?

Accepted Answer

The ability of floodwaters to move freely across the floodplain without obstruction

Answer

The structural connection between levee panels

Answer

The efficiency of stormwater inlets in capturing runoff

Answer

The link between FEMA's mapping database and local GIS systems

Question 4

In a Detailed Flood Insurance Study, cross-section data is used in hydraulic modeling to determine:

Accepted Answer

Water surface elevations at specific locations along a stream

Answer

Soil permeability

Answer

Storm sewer capacity

Answer

Groundwater recharge rates

Question 5

What does a Flood Insurance Rate Map (FIRM) show that an older Flood Hazard Boundary Map (FHBM) did not?

Accepted Answer

Base Flood Elevations and insurance risk zones

Answer

The general location of the 100-year floodplain only

Answer

Historical flood extents from recorded events

Answer

Levee certification status

Question 6

The 'regulatory floodway fringe' (flood fringe) is defined as:

Accepted Answer

The portion of the 100-year floodplain outside the floodway that can accommodate limited development

Answer

The area within the floodway where development is prohibited

Answer

The area between the 10-year and 50-year flood boundaries

Answer

The coastal zone subject to wave run-up