CESSWI Exam Questions with Verified Answers
|2026/2027 Update | A+ Graded
Mulching - Answer -application of plant residues or suitable materials to the surface. Mulching
helps to conserve moisture and modify surface temperature fluctuations, prevent surface
compaction or crusting, reduce runoff and erosion, control weeds and help establish plant cover
on soils subject to erosion.
Biotechnical slope protection advantages - Answer -usually less expensive than structural
no specialized installation skills
typically no heavy equipment needed
environmentally compatible
natural aesthetic appearance
provide wildlife habitat and cover
PLS - Answer -Pure Live Seed
PLS = germination % x purity / 100
Accretion - Answer -outward growth of bank or shore by sedimentation. increase of extension
of boundaries of land by action of natural forces
1|Page
,aggradation - Answer -general and progressive raising of a stream bed by deposition of
sediment. Modification of the earths surface in the direction of uniformity of grade or slope by
deposition as in a river bed.
aggressive - Answer -refers to the corrosive properties of soil and water
alluvial - Answer -deposits of silts, sands, gravels and similar detrital material that have been
transported by running water
arroyo - Answer -waterway of an ephemeral stream deeply carved in rock or ancient alluvium
avulsion - Answer -a forcible separation, the sudden removal of land from the estate of one
person to that of another, shift in channel location
backing layer - Answer -layer of graded rock between rock riprap and underlying engineering
fabric or filter layer to prevent extrusion of the soil or filter layer material through the riprap
block - Answer -precast prismatic unit for riprap structure
boil - Answer -turbulent break in a water surface by upwelling
2|Page
,boom - Answer -floating log or similar element designed to dampen surface waves or control
movement of drift
bore - Answer -transient solitary wave in a narrow or convergine channel advancing with a steep
turbulent front, product of flash floods or incoming tides
boulder - Answer -larges rock transported by a stream or rolled in the surf
bulking - Answer -increase in volume of flow due to air entrainment, debris, bedload or
suspended sediment
camber - Answer -upward adjustment of the profile of a drainage facility under a heavy loading
(usually a high embankment) and poor soil conditions, so that as the drainage facility settles it
approaches the design profile
capillarity - Answer -attraction between water and soil particles that cause water to move in any
direction through the soil mass regardless of gravitational forces
cavitation - Answer -erosion by suction, especially in the partial vacuum of a diverging jet
3|Page
, celerity - Answer -velocity of a moving wave, as distinguished from velocity of particles
oscillating in the wave
cienega - Answer -swamp formed by water rising to the surface at a fault
cobble - Answer -rock smaller than a boulder and larger than gravel
cone - Answer -physio-graphic form of sediment deposit washed from a gorge channel onto an
open plain, a debris cone also called an alluvial fan
corrasion - Answer -erosion or scour by abrasion in flowing water
cradle - Answer -a concrete base generally constructed to fit the shape of a structure that is to
be forced through earthen material by a jacking operation. The cradle is constructed to line and
grade.
crib - Answer -an open frame structure loaded with earth or stone ballast to act as a baffle in
bank protection
4|Page
|2026/2027 Update | A+ Graded
Mulching - Answer -application of plant residues or suitable materials to the surface. Mulching
helps to conserve moisture and modify surface temperature fluctuations, prevent surface
compaction or crusting, reduce runoff and erosion, control weeds and help establish plant cover
on soils subject to erosion.
Biotechnical slope protection advantages - Answer -usually less expensive than structural
no specialized installation skills
typically no heavy equipment needed
environmentally compatible
natural aesthetic appearance
provide wildlife habitat and cover
PLS - Answer -Pure Live Seed
PLS = germination % x purity / 100
Accretion - Answer -outward growth of bank or shore by sedimentation. increase of extension
of boundaries of land by action of natural forces
1|Page
,aggradation - Answer -general and progressive raising of a stream bed by deposition of
sediment. Modification of the earths surface in the direction of uniformity of grade or slope by
deposition as in a river bed.
aggressive - Answer -refers to the corrosive properties of soil and water
alluvial - Answer -deposits of silts, sands, gravels and similar detrital material that have been
transported by running water
arroyo - Answer -waterway of an ephemeral stream deeply carved in rock or ancient alluvium
avulsion - Answer -a forcible separation, the sudden removal of land from the estate of one
person to that of another, shift in channel location
backing layer - Answer -layer of graded rock between rock riprap and underlying engineering
fabric or filter layer to prevent extrusion of the soil or filter layer material through the riprap
block - Answer -precast prismatic unit for riprap structure
boil - Answer -turbulent break in a water surface by upwelling
2|Page
,boom - Answer -floating log or similar element designed to dampen surface waves or control
movement of drift
bore - Answer -transient solitary wave in a narrow or convergine channel advancing with a steep
turbulent front, product of flash floods or incoming tides
boulder - Answer -larges rock transported by a stream or rolled in the surf
bulking - Answer -increase in volume of flow due to air entrainment, debris, bedload or
suspended sediment
camber - Answer -upward adjustment of the profile of a drainage facility under a heavy loading
(usually a high embankment) and poor soil conditions, so that as the drainage facility settles it
approaches the design profile
capillarity - Answer -attraction between water and soil particles that cause water to move in any
direction through the soil mass regardless of gravitational forces
cavitation - Answer -erosion by suction, especially in the partial vacuum of a diverging jet
3|Page
, celerity - Answer -velocity of a moving wave, as distinguished from velocity of particles
oscillating in the wave
cienega - Answer -swamp formed by water rising to the surface at a fault
cobble - Answer -rock smaller than a boulder and larger than gravel
cone - Answer -physio-graphic form of sediment deposit washed from a gorge channel onto an
open plain, a debris cone also called an alluvial fan
corrasion - Answer -erosion or scour by abrasion in flowing water
cradle - Answer -a concrete base generally constructed to fit the shape of a structure that is to
be forced through earthen material by a jacking operation. The cradle is constructed to line and
grade.
crib - Answer -an open frame structure loaded with earth or stone ballast to act as a baffle in
bank protection
4|Page
