Transcript Document

On-Site Challenge:
Water Harvesting Terms
and Concepts
Quiz 1
(Use the terms & concepts list in the MESA
Day Handbook along with the “Rainwater
Harvesting for Drylands” resource book)
The landscaped feature below reduces the
steepness of a section of a slope, reducing runoff
and erosion while increasing water infiltration.
What is it called?
ANSWER: Terrace
Terraces can be small-scale like in the previous slide
or large-scale (below). Look for the use of terraces in
hilly areas where you live.
The photo shows _______________ of a stream;
which typically straightens & constricts water flow by
sealing & smoothing the banks and sometimes beds
of a waterway.
ANSWER: Channelization
• Aerial photo showing channelization of the Rio
Grande in the Mesilla Valley (southern New
Mexico).
Channelization increases the _________ of
water flow through & downstream of the
channelized area, reducing infiltration of
water into the soil and sometimes
deepening the channel.
A) Volume
B) Velocity
C) Width
Answer: Velocity
• Left Photo: note the steep
drop below the culvert
where the pressure &
velocity of water has
scoured the ground away
• Right Photo: Rocks
placed below culvert to
slow velocity & prevent
erosion
When water flow is not channelized
and is allowed to spread out and slow
down what are the benefit/s?
A) Reduced erosion
B) Water is allowed to infiltrate into the ground
(recharges groundwater)
C) Neither A nor B
D) Both A & B
ANSWER: BOTH A & B
Reduces erosion and allows water to infiltrate
into the ground.
PHOTO: An unchannelized river with
natural meanders
(curves)
A drainage pipe made to transport water
beneath a roadway is called a
_________________?
ANSWER: Culvert
• Photo: box culverts for the New Mexico
Department of Transportation
near Hillsboro New Mexico
Which of these household water uses
does NOT produce grey-water?
Answer:
• Greywater is water that drains from your
household sinks, tubs, showers and washing
machine. It does not include water draining
from the toilet which is called blackwater.
Percolation is the ________movement of
water through the soil.
A) upward
B) downward
C) rapid
D) none of the above
ANSWER: B) downward
Which driveway is impervious?
A
B
Answer: A
• Water is not able to percolate through the
impervious cement surface of this driveway
What is the advantage of permeable
paving?
A) Allows water to infiltrate the soil
B) Passively irrigates adjoining plants
C) Dissipates heat
D) Reduces soil compaction
E) Allows tree roots to breathe
F) Filters pollutants
G) Decreases the need for expensive drainage
infrastructure
H) all of the above
Answer: All of the above
• Photo: The permeable landscaping in a desert
backyard allows rainwater to infiltrate the
ground & create a cooler, greener living
environment
A porous layer of organic matter or rock on the
surface of the soil that increases porosity and
fertility of the underlying soil AND reduces
moisture loss to evaporation is called
_________.
ANSWER: Mulch
Pecan Mulch
Mulches
often reflect
what is
available in
that region.
What might
be readily
available
mulch where
you live?
Wood bark
Oyster Shell Mulch
Gravel much
The subterranean layers of
sedimentary particles (sand,
gravel, rocks) laid down over
geologic time, in which water
fills the tiny spaces between
the particles is called an
____________
ANSWER: Aquifer
PREVIOUS SLIDE: USGS aquifer map of New Mexico