CESSWI FINAL PAPER 2026 COMPLETE
QUESTIONS WITH SOLUTIONS
◉Other erosion. Answer: soil loss from gullies, channels and other
concentrated flow may be determined by calculating the annual
volume of soil removed from the eroded areas.
Annual tons of soil loss can be determined by multiply the volume by
the weight of the soil
◉Partial year soil loss. Answer: a value obtained with RUSLE may be
modified by a factor M to estimate the soil loss for a portion of the
year
◉Hydrologic Cycle. Answer: Precipitation - Surface Runoff -
Infiltration - Transipiration- Percolation -Evaporation
◉Runoff Volume. Answer: Q = volume of the runoff in watershed
inches multiplied by the watershed area.
◉Factors affecting runoff. Answer: precipitation (P)
,time
watershed area
ground cover
antecedent moisture condition
storage in the watershed
soil permeability
◉Peak Rate of Runoff. Answer: Q p as cubic feet per second cfs
◉Time. Answer: Time of Concentration (Tc) is the time it take runoff
to travel from the hydraulically most distant point in the watershed
to the design point. The time of concentration is computed by
summing all the travel times for consecutive components of the
conveyance system
◉Travel time. Answer: Travel time (Tt) it takes runoff to travel from
one location to another in a watershed
◉sheet flow. Answer: flow over the upland area of the watershed
where there is no defined channel or watercourse.
◉Shallow concentrated flow. Answer: occurs once flow begins to
flow rills. This generally begins within 150 feet of the onset of runoff
and seldom after 300 feet of sheet flow
,◉channel flow. Answer: open channel flow occurs where channels
are visible on aerial photos where blue lines exist on USGS quad
sheets or channel existence can be verified in the field. Mannings
equation generally used to predict velocity for channel flow
◉Peak Discharge. Answer: qp = qu x A x Q x Fp
qp= peak discharge
qu = unit peak discharge
A = watershed area
q = runoff in watershed inches
Fp = adjustment for watershed storage
◉Soil Permeability. Answer: Soils are classified into hydrologic soil
groups (HSG) to indicate the minimum rate of infiltration obtained
for bare soil after prolonged wetting. The HSGs are one element
used in runoff curve numbers. The infiltration rate is the rate at
which water enters the soil at the soil surface. HSG also indicates the
transmission rate (rate at which the water moves within the soil),
which is controlled by the soil profile.
◉Initial Abstration. Answer: Ia is the sum of the losses that occur
before runoff begins.
, ◉Hydrologic Soil Group A. Answer: Group A soils have low runoff
potential and high infiltration rates even when wetted. They consist
chiefly of deep, well to excessively drained sands or gravels and have
a high rate of water transmission (greater than 0.30 in/hr)
◉Hydrologic Soil Group B. Answer: Group B soils have moderate
infiltration rates when thoroughly wetted and consist chiefly of
moderately deep to dep. Moderately well to well drained solid with
moderately fine to moderately coarse textures. These soils have a
moderate rate of water transmission. (0.15 - 0.30 in/hr)
◉Hydrologic Soil Group C. Answer: Group C soils have low
infiltration rate when thoroughly wetted and consist chiefly of soils
with a layer that impedes downward movement of water and soils
with moderately fine to fine texture. These soils ahve a low rate of
water transmission (0.05 - 0.15 in/hr)
◉Hydrologic Soil Group D. Answer: Group D soils have a high runoff
potential. They have very low infiltration rates when thoroughly
wetted and consist chiefly of clay soils with high swelling potential,
soils with a high permanent water table, soils with a claypan or clay
layer at or near the surface, and shallow soils over nearly
impervious material. These soils have a very low rate of water
transmission (0-0.05 in/hr)
QUESTIONS WITH SOLUTIONS
◉Other erosion. Answer: soil loss from gullies, channels and other
concentrated flow may be determined by calculating the annual
volume of soil removed from the eroded areas.
Annual tons of soil loss can be determined by multiply the volume by
the weight of the soil
◉Partial year soil loss. Answer: a value obtained with RUSLE may be
modified by a factor M to estimate the soil loss for a portion of the
year
◉Hydrologic Cycle. Answer: Precipitation - Surface Runoff -
Infiltration - Transipiration- Percolation -Evaporation
◉Runoff Volume. Answer: Q = volume of the runoff in watershed
inches multiplied by the watershed area.
◉Factors affecting runoff. Answer: precipitation (P)
,time
watershed area
ground cover
antecedent moisture condition
storage in the watershed
soil permeability
◉Peak Rate of Runoff. Answer: Q p as cubic feet per second cfs
◉Time. Answer: Time of Concentration (Tc) is the time it take runoff
to travel from the hydraulically most distant point in the watershed
to the design point. The time of concentration is computed by
summing all the travel times for consecutive components of the
conveyance system
◉Travel time. Answer: Travel time (Tt) it takes runoff to travel from
one location to another in a watershed
◉sheet flow. Answer: flow over the upland area of the watershed
where there is no defined channel or watercourse.
◉Shallow concentrated flow. Answer: occurs once flow begins to
flow rills. This generally begins within 150 feet of the onset of runoff
and seldom after 300 feet of sheet flow
,◉channel flow. Answer: open channel flow occurs where channels
are visible on aerial photos where blue lines exist on USGS quad
sheets or channel existence can be verified in the field. Mannings
equation generally used to predict velocity for channel flow
◉Peak Discharge. Answer: qp = qu x A x Q x Fp
qp= peak discharge
qu = unit peak discharge
A = watershed area
q = runoff in watershed inches
Fp = adjustment for watershed storage
◉Soil Permeability. Answer: Soils are classified into hydrologic soil
groups (HSG) to indicate the minimum rate of infiltration obtained
for bare soil after prolonged wetting. The HSGs are one element
used in runoff curve numbers. The infiltration rate is the rate at
which water enters the soil at the soil surface. HSG also indicates the
transmission rate (rate at which the water moves within the soil),
which is controlled by the soil profile.
◉Initial Abstration. Answer: Ia is the sum of the losses that occur
before runoff begins.
, ◉Hydrologic Soil Group A. Answer: Group A soils have low runoff
potential and high infiltration rates even when wetted. They consist
chiefly of deep, well to excessively drained sands or gravels and have
a high rate of water transmission (greater than 0.30 in/hr)
◉Hydrologic Soil Group B. Answer: Group B soils have moderate
infiltration rates when thoroughly wetted and consist chiefly of
moderately deep to dep. Moderately well to well drained solid with
moderately fine to moderately coarse textures. These soils have a
moderate rate of water transmission. (0.15 - 0.30 in/hr)
◉Hydrologic Soil Group C. Answer: Group C soils have low
infiltration rate when thoroughly wetted and consist chiefly of soils
with a layer that impedes downward movement of water and soils
with moderately fine to fine texture. These soils ahve a low rate of
water transmission (0.05 - 0.15 in/hr)
◉Hydrologic Soil Group D. Answer: Group D soils have a high runoff
potential. They have very low infiltration rates when thoroughly
wetted and consist chiefly of clay soils with high swelling potential,
soils with a high permanent water table, soils with a claypan or clay
layer at or near the surface, and shallow soils over nearly
impervious material. These soils have a very low rate of water
transmission (0-0.05 in/hr)
