AASHTAASHTO

Question 1

A general and progressive buildup or raising of the longitudinal profile of the channel bed as a result of sediment deposition.

Answer 1

Aggradation—

Question 2

An unobstructed, relatively flat area beyond the edge of the traveled way for the recovery of errant vehicles. The traveled way does not include shoulders or auxiliary lanes.

Answer 2

Clear Zone—

Question 3

An unobstructed horizontal or vertical space.

Answer 3

Clearance—

Question 4

A general and progressive lowering of the longitudinal profile of the channel bed as a result of long-term
erosion.

Answer 4

Degradation—

Question 5

Maximum flow of water a bridge is expected to accommodate without exceeding the adopted design constraints.

Answer 5

Design Discharge—

Question 6

The flood flow equal to or less than the 100-yr flood that creates the deepest scour at bridge foundations.

Answer 6

Design Flood for Bridge Scour—

Question 7

The peak discharge, volume, stage, or wave crest elevation and its associated probability of exceedence that are selected for the design of a highway or bridge over a watercourse or floodplain.

Answer 7

Design Flood for Waterway Opening—

Question 8

A storm water management facility that impounds runoff and temporarily discharges it through a hydraulic outlet structure to a downstream conveyance system.

Answer 8

Detention Basin—

Question 9

Linear depression in the bottom of components to cause water flowing on the surface to drop.

Answer 9

Drip Groove—

Question 10

The flood due to storm and/or tide having a 0.2 percent chance of being equaled or exceeded in any given year.

Answer 10

Five-Hundred-Year Flood—

Question 11

Scour in a channel or on a floodplain that is not localized at a pier or other obstruction to flow.

Answer 11

General or Contraction Scour—

Question 12

The science concerned with the behavior and flow of liquids, especially in pipes and channels.

Answer 12

Hydraulics—

Question 13

The science concerned with the occurrence, distribution, and circulation of water on the earth, including precipitation, runoff, and groundwater.

Answer 13

Hydrology—

Question 14

Scour in a channel or on a floodplain that is localized at a pier, abutment, or other obstruction to flow.

Answer 14

Local Scour—

Question 15

Flood flows derived from two or more causative factors, e.g., a spring tide driven by hurricane- generated onshore winds or rainfall on a snowpack.

Answer 15

Mixed Population Flood—

Question 16

The flood due to storm and/or tide having a 1 percent chance of being equaled or exceeded in any given year.

Answer 16

One-Hundred-Year Flood—

Question 17

The flood flow that, if exceeded, results in flow over a highway or bridge, over a watershed divide, or through structures provided for emergency relief. The worst-case scour condition may be caused by the overtopping flood.

Answer 17

Overtopping Flood—

Question 18

An opening in an embankment on a floodplain to permit passage of overbank flow.

Answer 18

Relief Bridge—

Question 19

Any configuration constructed in a stream or placed on, adjacent to, or in the vicinity of a streambank to deflect current, induce sediment deposition, induce scour, or in some other way alter the flow and sediment regimens of the stream.

Answer 19

River Training Structure—

Question 20

A device to drain water through the deck.

Answer 20

Scupper—

Question 21

Unobstructed space for exclusive pedestrian use between barriers or between a curb and a barrier.

Answer 21

Sidewalk Width—

Question 22

A tide of increased range that occurs about every two weeks when the moon is full or new.

Answer 22

Spring Tide—

Question 23

A condition that exists when a stream has a bed slope and cross-section that allows its channel to transport the water and sediment delivered from the upstream watershed without significant degradation, aggradation, or bank erosion.

Answer 23

Stable Channel—

Question 24

The study of a stream and its floodplain with regard to its land forms, the general configuration of its surface, and the changes that take place due to erosion and the buildup of erosional debris.

Answer 24

Stream Geomorphology—

Question 25

A tilting of the roadway surface to partially counterbalance the centrifugal forces on vehicles on horizontal curves.

Answer 25

Superelevation—

Question 26

Any flood or tidal flow with a flow rate greater than that of the 100-yr flood but not greater than a 500-yr
flood.

Answer 26

Superflood—

Question 27

The periodic rise and fall of the earth′s ocean that results from the effect of the moon and sun acting on a rotating
earth.

Answer 27

Tide—

Question 28

An area confined by drainage divides, and often having only one outlet for discharge; the total drainage area contributing runoff to a single point.

Answer 28

Watershed—

Question 29

Any stream, river, pond, lake, or ocean.

Answer 29

Waterway—

Question 30

Width or area of bridge opening at a specified stage, and measured normal to principal direction of
flow.

Answer 30

Waterway Opening—