CFS Technology & Digital Tools 2

Question 1

Which file format is the standard for exchanging LiDAR point cloud data used in floodplain elevation mapping?

Accepted Answer

LAS/LAZ

Answer

LAS (and its compressed variant LAZ) is the industry-standard binary format for storing airborne LiDAR point cloud data.

Question 2

In GIS-based floodplain analysis, a Digital Elevation Model (DEM) derived from LiDAR typically has a horizontal resolution of:

Accepted Answer

1–3 meters

Answer

Modern LiDAR-derived DEMs for floodplain mapping commonly achieve 1–3 meter horizontal resolution, far superior to older 30-meter SRTM data.

Question 3

What does the acronym GNSS stand for in the context of field surveying for floodplain studies?

Accepted Answer

Global Navigation Satellite System

Answer

GNSS encompasses all satellite constellations (GPS, GLONASS, Galileo, BeiDou) used for positioning, making it the broad term surveyors use.

Question 4

A surveyor uses Real-Time Kinematic (RTK) GNSS for establishing benchmark elevations in a floodplain survey. The primary advantage of RTK over static post-processing is:

Accepted Answer

Centimeter-level accuracy delivered in real time

Answer

RTK GNSS uses a base station broadcasting corrections to achieve centimeter-level positional accuracy instantly in the field.

Question 5

When using FEMA's Map Service Center (MSC) online, a floodplain surveyor can primarily retrieve:

Accepted Answer

Official FIRM panels and FIS reports

Answer

FEMA's MSC is the official portal for accessing current Flood Insurance Rate Map (FIRM) panels and Flood Insurance Study (FIS) reports.

(CFS) Certified Floodplain Surveyor Practice Test

(CFS) Certified Floodplain Surveyor Practice Test

CFS Technology & Digital Tools 2