AGSM 335: Exam 1

Normal pool

Average depth of a lake

Event storage

Design volume above normal pool to hold runoff after a rain event

Freeboard

Vertical distance from maintained pond level to maximum overflow level

Lagoon

Open pond where wastewater is mitigated

Runoff

Occurs on a permeable surface when the surface layer is saturated

Impervious surface

Surface that does not allow measurable infiltration of water

Volumetric flow rate units

GPM, gallons per minute

Infiltration rate

Inches per hour (IPH)

Velocity units

FPS, feet per second

1 acre foot of water

6 inches of water on 2 acres of land

Unit used for volume

Gallons

Unit used for large volumes of water on a farm

Acre-feet

Unit used for infiltration rate

IPH

Velocity

Feet per second

Unit used for area

Square feet

Volumetric flow rate

Gallon per minute

Soil erosion

Process by which soil particles are detached from the larger body of soil and then transported to a new location

Accelerated Erosion

Increase in soil erosion and sediment production above the level of natural erosion

Apathy

Lack of passion or indifference

Mechanical

Structures, tillage equipment, technique pipelines, retention basin, waterways

Vegetative

Cover crops, trees, crop rotations, all things related to plant growth

Soil texture

Sand, silt, clay

Topography

Slope of terrain

Structure of soil

Aggregates, pore space, clay particles

Runoff

Surface water when infiltration rate is exceeded

Rod readings, such as 2.56 are in -

Feet

In the past and present, as population has increased (along with the need for food), a typical response has been to

Cut down trees, clear land, increase area under protection

In lab, we took a rod reading of multiple rods like “A” and “B” respectively. What is the “meaning” of the difference in the rod readings for “A” and “B”?

The difference in elevation between the rods is about 0.07-0.08 feet

Soil loss due to erosion is measured in

Tons per acre

The ______ need to be defined and not blurry when taking a rod reading

Crosshairs

Soil erosion occurs during large, significant rain events (thunderstorms) and small, long-term rain events

True

The formula for computing distance using stadia lines is:

Bottom Stadia - Top Stadia = distance (ft)

False

This formula can be used to determine the required depth of a pond. When the area of the pond and volume of runoff it will hold is known.

Volume = Area x Depth

True

German farmers looked for certain species of _____ in the Midwest to identify familiar and productive soil types.

Trees