INSTRUCTION MANUAL
SPONSORED
BY THE
EMBARRAS RIVER MANAGEMENT ASSOCIATION
ILLINOIS ENVIRONMENTAL PROTECTION AGENCY
NATURAL RESOURCES CONSERVATION SERVICE
MONSANTO, INC.
SOIL & WATER CONSERVATION DISTRICTS OF
DOUGLAS,
COLES, CUMBERLAND, JASPER, CRAWFORD, CLARK, CHAMPAIGN, LAWRENCE,
EFFINGHAM,
EDGAR, VERMILION & RICHLAND COUNTIES
RAINFALL SIMULATOR INSTRUCTION MANUAL
The
Rainfall Simulator comes in an enclosed trailer as a completely
equipped and
self-contained unit.
As long
as the battery is charged and the water tank filled, the RSU can be
transported
to remote locations for demonstration purposes.
RAINFALL SIMULATOR INSTRUCTION MANUAL
TABLE OF CONTENTS
I.
INTRODUCTION
II. OVERVIEW OF THE RAINFALL
SIMULATOR PRESENTATION
III.
TOWING THE RSU TO THE DEMONSTRATION SITE
IV.
PRE-PRESENTATION PREPARATION
V.
SETTING UP THE RAINFALL SIMULATOR
VI.
PREPARING FOR THE PRESENTATION
VII.
POST PRESENTATION CLEAN-UP
VIII.
RAINFALL SIMULATOR
PRESENTATION GUIDELINE
IX. EDUCATIONAL SIGNS
PROVIDED
X.
ADDITIONAL EDUCATIONAL MATERIAL
The Embarras River
Management
Association (ERMA) is a "grassroots" organization of citizens
dedicated to the development and implementation of a comprehensive
natural
resource plan for the Embarras River Watershed. The
Embarras River begins on the campus of the University of
Illinois and flows generally southward through the eight counties of
Champaign,
Douglas, Coles, Cumberland, Jasper, Richland, Crawford and Lawrence,
until it
converges with the Wabash River, a distance of 192 miles.
The Embarras River basin, which
encompasses over 1.5 million acres, includes additional drainage area
from the
four counties of Vermilion, Edgar, Effingham and Clark, and affects a
population of over 130,000 citizens.
The goal of ERMA is to promote conservation projects and
practices that
improve drinking water quality and quantity, reduce soil erosion and
stream
sedimentation, protect and enhance fish and wildlife habitat, alleviate
flooding to communities and cropland, and improve economic and
recreational
opportunities within the Embarras River Watershed.
A vital
component of the Embarras River Management Association's (ERMA)
plan of work is an aggressive conservation and environmental education
outreach
program. In February of 2003,
ERMA's Rainfall Simulator Unit (RSU) project was selected for funding
under the
EPA Section 319 Nonpoint Source Pollution Control Grant Program. Through this funding along with private
donations, ERMA has built six rainfall simulator units to be utilized
by the
NRCS/SWCD offices located in the Embarras Watershed and surrounding
counties. The rainfall simulator unit
provides a very effective visual demonstration of the power of a
raindrop on
the soil surface, and the value of vegetation or crop residue in
reducing soil
erosion and nutrient leaching, while improving soil moisture retention
and
water quality. The added benefit
of enhanced wildlife habitat can also be emphasized.
These units are an effective conservation education tool to
be utilized at field days, tours, schools and other events. The conservation education lessons that
can be derived from the use of the Rainfall Simulators are only limited
by the
imagination. Over time and with
additional funding, we hope to expand the educational components of the
units. For example, we are already
looking at how a stream table could be incorporated into the units.
The
response to the rainfall simulator units has been very exciting and
gratifying. The units were
utilized extensively at many events during 2003, including the Illinois
State
Fair and the IEPA's Splash Day in Springfield, the Farm Progress Show
in
Vermilion County; Palestine Rodeo Days in Crawford County; a Farm
Manager
Conference, Wildlife Workshop and a seed companyÕs field day in
Douglas County;
an FFA Soil Judging Contest at Lakeland College in Coles County; a
Water
Quality Education Day for students in Clark County; a Teacher Workshop
with the
Coles County SWCD; and Conservation Education Days for elementary
school
students in conjunction with the SWCDs of Douglas, Jasper, Effingham,
Fayette
and Piatt counties. In 2004, they
have already been utilized by the NRCS/SWCDs, Ag Extension, IEPA and
IDOA at
events such as National FFA Week, Conservation Education Days and Earth
Day
presentations for students in Coles, Douglas, Champaign, Ford, Piatt,
Crawford,
Jasper, Moultrie, Cumberland, Edgar, Vermilion, Macon, and Sangamon
counties. The RSU was also demonstrated
for a
group of 5th grade students from a private school in
Chicago, who
rode a bus down to Piatt County to experience a "day on the farm", and
learn
about agriculture and conservation.
ERMA initiated the
rainfall
simulators project because we realize the great importance of
maintaining conservation
and environmental education programs.
Through the implementation of conservation practices and
watershed
planning over the years, great gains have been accomplished in
protecting this
country's most valuable natural resources; its rich, productive topsoil
and
fresh water. There is no doubt
that the United States' rise to becoming the most powerful nation in
the world
is based on the fact that its citizens are provided with an abundant
supply of
food, shelter, and water. In order
to remain a strong nation, we must maintain good stewardship of our
natural resources
through unwavering dedication to our conservation and watershed
programs.
OVERVIEW OF THE
RAINFALL SIMULATOR PRESENTATION
The Rainfall
Simulator is
designed to show what happens to topsoil on cropland fields or
construction
sites during rainstorms. It
demonstrates the benefits of crop residue management in protecting the
topsoil during
rainstorms. The simulator shows
the results of a 2-3 inch rainstorm in approximately 15-20 minutes. A rainstorm of this intensity has the
potential of causing excessive runoff with severe soil loss.
Up to five soil
trays can be
placed below the oscillating raindrop nozzle, which is special-sized to
create
a droplet very close to what occurs with a natural rainstorm. Dry, loose soil is poured and leveled
in the 10"x 20"x 2.5 trays, with varying levels of crop residue then
placed on
the soil surface. The five soil
trays can be set at up to an 11 percent slope, which would be
considered a
steep slope in cropland conditions.
The percent slope is how much elevation rise there is in 100
feet. In this example, it would be
comparable
to a crop field with 11 foot of rise in elevation in 100 feet of
distance.
The crop residue in
the soil
trays can be wheat straw, soybean stubble, or corn stalks.
The residue is placed on the soil
surface and not incorporated into the soil. Incorporation
would not add additional protective
benefit. The residue will provide
the same protective benefit for wind and water erosion just lying on
the soil
surface.
The soil trays
exhibit
various levels of crop residue.
The simulator shows the protective benefit of crop residue is in
direct
proportion to the level of residue covering the soil surface, the more
crop
residue, the less soil loss. A
photograph of a raindrop, magnified approximately 50 times, is included
with
the traveling demonstration. The
raindrop photograph shows the explosive energy released as a raindrop
hits a
bare soil surface. A straight down
raindrop travels at approximately 15 to 20 miles per hour, depending on
the
size of the raindrop, and separates the soil particles upon impact with
bare
ground. The loosened soil
particles are then pulled downhill by the force of gravity, resulting
in soil
erosion. When a raindrop hits a
piece of crop residue, the explosive energy is absorbed by the residue,
which
leaves the soil particles in place.
The rainwater then runs off the residue, percolates into the
soil
profile and is stored for future crop needs.
Many people believe
that soil
crusting occurs after a rainstorm has ended and the sun comes out
baking the
ground. But in reality, soil
crusting occurs in the first few minutes of a rainstorm.
Raindrops hitting bare ground will
separate soil particles and form a sealed barrier, or crust, which
greatly
slows the percolation of water into the soil profile.
This can be demonstrated with the rainfall simulator. The 0% residue or bare soil tray will
crust over in the first few minutes of the rainfall, simulating what
happens to
the soil in real field conditions.
Soil crusting does not allow the water to infiltrate into the
soil but
rather forces the water to run off the field, carrying soil particles
loosened
by the raindrops' miniature explosions.
This can be proved at the end of the demonstration by turning
over the
soil trays that have 0% cover and 100% cover. The
soil in the 0% cover tray will only be wet approximately
half way down, while the remaining soil in the bottom of the 2.5" tray
is
dry. In contrast, the soil in the
100% cover tray will be completely saturated with water to the bottom
of the
tray.
The jars placed at the
bottom of each tray also confirm this. While
the receiving jar for the 0%
cover tray contains a large amount of sediment-laden water, the
receiving jar
for the 100% cover tray contains much less water, and this water is
virtually
free of any sediment.
In past
demonstrations, the
jugs under the 0% and 30% cover trays had the water drained off after
the
sediment had settled. The tray
area was calculated on a per acre basis and the sediment weighed to
determine
how much soil was lost during this one rainstorm. The
0% tray had lost 7.5 tons per acre and the 30% tray had
lost 1.5 tons per acre.
Fields with
terraces,
waterways, and crop residue provide the best protection against water
erosion. The residue protects the
soil from the force of the raindrops.
The terraces walk the rain water slowly off the field to a
grassed
waterway. These grass strips at
the bottom of cropland fields or next to streams are very effective in
intercepting or trapping soil sediment, organics, pesticides and other
potential pollutants before they reach a body of water.
The protective water quality benefits
of grass buffer strips can also be demonstrated with the simulator. A soil tray with sod can be included in
the demonstration to show the value of filter strips.
After a rainfall cycle has been completed, it is quite
noticeable that the collection jar under the sod tray contains much
less water,
and that the water is very clean and clear.
During the
presentation is
also a good time to talk about soil quality and soil health. A handful of soil can be displayed and
the fact stated that this amount of healthy soil may contain more soil
microbes
than there are people on the face of the earth (6 billion). It can then be stressed that the
required food for these soil microbes is crop residue.
It can also be stated that healthy
topsoil is a living, breathing organism with the air in the upper 8
inches of a
well-drained soil being completely renewed about every hour. In addition, the value and importance
of earthworms for maintaining good soil quality and health can be
emphasized,
and the fact that increased tillage results in decreased earthworm
populations
in a cropland field.
The harmful effects
of
destroying soil structure with tillage equipment can be quickly and
easily
demonstrated using Rice Krispies cereal.
In the demonstration, no-till soil structure is compared to a
bowl of
Rice Krispies cereal, i.e. a blocky texture with air spaces and worm
channels. For the demonstration, fill two
clear
plastic cups with Rice Krispies cereal.
Using a wood dowel, pulverize and grind up the cereal in one of
the cups
to simulate the breaking up of soil structure by frequent tillage
operations. Now pour water over
the cereal in both cups to show what happens during a rainstorm. The water just sits on top of the
cupful of ground up Rice Krispies with very little water percolating
downward. The water poured into
the cup of whole Rice Krispies immediately percolates to the bottom of
the cup. *To add humor, use milk in the
demonstration and follow-up by stating that using no-till farming
allows one to
have time for breakfast in the morning, rather than hurrying to the
fields like
the conventional farmer to do recreational tillage.
Utilizing the
rainfall
simulator for conservation education events can bring about better crop
residue
management on the land that will make a difference for better soil and
water
quality.
TOWING THE RSU TO
THE DEMONSTRATION SITE
Transporting
the RSU trailer requires a vehicle equipped for towing.
The trailer requires a 2" ball hitch, hook-up
for the safety chains, and electrical plug-in.
After
hooking the trailer up to the towing vehicle, be sure to insert the
safety pin through
the hitch latch. Cross and fasten
the trailer's safety chains to the towing vehicle.
The
electrical hookup requires a standard 4 prong flat plug-in. If the towing vehicle has a round
electrical plug-in, an adaptor may be utilized like the one shown on
the right.
Much
thought and planning has gone into equipping and organizing the
rainfall
simulator trailers. In the above
photo, note all of the equipment and the storage locations.
A
tool box has been provided along with some basic tools and materials. A First Aid Kit to treat minor injuries
has also been supplied and is located in the top of the tool box.
BATTERY: The 12 volt
battery installed in the trailer supplies power to the water pump and
rain head
motor. Depending on the amount of
daily use, a fully charged battery can last up to several days before
requiring
re-charging. The battery charger
installed in the trailer is hooked up directly to the 12 volt battery. To determine the level of charge left
in the battery, utilize the electrical cord supplied in the trailer to
plug the
charger in and check the charge meter.
If charging is needed, let the charger run for at least 1 to 2
hours. It is recommended that the charger
switch be left set to automatic so that the charger will automatically
shut off
when the battery reaches full charge.
Leaving the charger on manual charge may cause the battery to
explode by
being over-charged. After charging
is completed, disconnect the power cord to the charger, wind the cord
up on its
spool, and return it to the trailer.
WATER
TANK:
Before beginning to fill the tank, be sure to close the
valve to the floor drain. Note the
photo on the left. Observe that
the yellow handle on the valve to the floor drain is perpendicular to
the hose
on which it is located, thereby indicating it is closed.
Note that the yellow handle on the
valve for the water supply hose to the pump is parallel with the hose
on which
it is located, therefore it is open.
Utilize the garden hose provided and secure it to the tank by
hooking
one end of the bungee cord to the hose and the other end to the handle
of the
Crop Residue Bin. This will
prevent the water hose from falling out during the filling process. The water tank can now be filled with
up to 110 gallons of clean water.
SOIL: To keep
the demonstration more relevant, it is recommended that soils
representative of
the local area be utilized in the trays.
Suggested local sources include agricultural fields, home
gardens, or in
bulk from a garden center. Bagged
soil purchased from a store is not recommended because it is unusually
high in
peat and not representative of the local soils. To
avoid having to obtain soil for each demonstration, a
soil storage bin has been provided.
The bin should be filled with good dry soil that doesnÕt
contain any
clods. Cloddy or very wet soil is
difficult to use and does not work well.
Two shovels and two 5 gallon buckets have been provided to aid
soil
acquisition. Note photo below.
CROP RESIDUE: A crop
residue storage bin has been provided.
Crop residues that can be utilized for the demonstrations
include corn
stalks, soybean stubble, and wheat straw.
It is recommended that the residue be dry, individually bagged,
and
stored in the bin. Note photo
above.
TRAYS:
Stainless steel trays have been provided for the demonstrations. They are stored as shown in the above
photographs. The trays may be
directly filled with soil, but cleanup is easier if a liner is utilized. The black plastic plant trays found at
garden centers work very well. The
trays are approximately 10.75Ó wide by 21Ó long, and
should be the type with
drainage holes in the bottom. Note
the black tray on the trailer floor in the photos at the top of the
page.
SOD: To
demonstrate the effectiveness of grass waterways and filter strips in
reducing
soil erosion and preserving water quality, it is recommended that one
of the
trays contain a sample of established sod. Sod
may be obtained from a garden center or by cutting it
from a yard or field border. To avoid
having to obtain sod for each presentation, it is suggested that
several
plastic nursery trays be filled with the sod at the beginning of the
season. This way the trays can be
rotated between presentations. The
life of the sod can be extended over several months by placing the sod
trays in
light or partial shade, watering as needed, fertilizing with
Miracle-Gro every
two weeks, and keeping it trimmed with scissors as needed.
SPECIAL
TRAYS:
Various scenarios can be demonstrated through the use of
special trays. In the photo above,
the tray is to be representative of all the impermeable surfaces found
in an
urban setting, such as concrete and asphalt roads, parking lots,
driveways and
sidewalks. It demonstrates 100%
runoff and is used to show the impact this scenario has on a watershed. A tray such as the one above is simple
to construct. In the tray shown
above, a piece of rubber roofing was wrapped around a rectangular piece
of
plywood and stapled. It was then
placed into the tray with supporting blocks placed underneath to hold
it up
with one end slightly lower than the other. Silicone
sealer was used to seal the mat to the tray
sides.
SIGNAGE: Small
signs that designate what each tray is demonstrating have been provided. The signs are to be inserted into the
stainless steel sign holders, which in turn are to be inserted into the
brackets located on the end of each tray.
Located on each door are large signs featuring photographs,
tables and
information covering topics such as conservation tillage, water
quality, and wildlife. These signs have
been provided for
presenters to utilize as supportive educational tools during their
presentations. Basically, the
posters can be utilized as the main guide for the presentation: As a guide, "Clean-Till" is represented
by the Zero percent residue tray; "Mulch-Till" is the 30% residue tray;
and "No-Till" is the 100% residue tray.
(Note: In the Environmental
Benefits poster, Number 5, "DCI" stands for "Daily Calorie Intake".)
The signage can be utilized
as a format and guide for the presentation. The
information they contain reinforces the conservation and
environmental lessons being demonstrated.
SETTING UP THE
RAINFALL SIMULATOR
The
rainfall simulator unit works best when it is sitting as level as
possible
front to back and side to side.
Try to choose a level demonstration site before unhooking the
trailer
from the towing vehicle. Utilizing
the level provided in the toolbox, check to see if the trailer is level
or not
by placing the level on a trailer fender.
If adjustment is needed, raise or lower the jack located on the
trailer
hitch. Cranking the jack handle
clockwise raises the trailer front and lowers the backend, while
cranking the
handle counter clockwise lowers the trailer front and raises the
backend.
Open the
back doors of the trailer and lock them in place by inserting the
supplied
brace rods into the brackets located on the trailer sides and doors. Unfasten the bungee cord holding the
track to the unit.
Carefully
grasp and lower the track. Check
for levelness by placing the level lengthwise on one of the tracks and
by
placing it on the cross piece running between the two tracks. Make needed adjustments by loosening
the jam nuts and screwing the leveling legs on the tracks in or out. Be sure to re-tighten the jam
nuts.
Grasp the rainfall
simulator
unit frame and carefully roll it out to the end of the tracks. Flip the locks on the track into place
behind the unitÕs wheels. Unfasten
the bungee cord holding the rain head water supply hose and electrical
cord
from the mast and lay them on the ground.
Make sure that the pin is not inserted through the hole in the mast. In order to raise the mast, flip the silver lever on the wench completely forward and crank the wench handle clockwise.
After the mast is
vertical, make
sure the holes in the masts are aligned, insert the pin and secure it. CAUTION:
Never
leave the mast unattended without the safety pin inserted as the mast
could
fall and cause damage or injury.
Connect the mast
hose to the
water supply hose coming from the water tank. Open
the water valve between the tank and the pump. The
middle photo shows the valve from
the tank to the pump in the open position and the valve to the floor
drain in
the closed position. The right
photo shows the pressure regulator and gauge. While
the water pressure to the rain head has been pre-set,
if the pressure becomes a problem, turn the bolt on top of the
regulator
clockwise to increase pressure or counterclockwise to decrease it.
Uncoil
the remote toggle switch cord (orange cord with black plug-in) and plug
the
cord into the orange cord protruding below the wall receptacle at the
back of
the trailer. Insert the yellow
plug for the rain head motor into the wall receptacle at the back of
the
trailer as shown. Be sure to match
up the cord prong design with the corresponding receptacle design.
PREPARING FOR
THE PRESENTATION
SLOPE
ADJUSTMENT:
The slope of the
table frame
that holds the trays is adjustable.
The top hole corresponds to an 11% slope; the second hole down
corresponds to a 7.3% slope (as shown in the photo to the left); the
third hole
down corresponds to 3.7% slope; and the bottom hole would correspond to
a 0%
slope or level. For most
demonstration purposes, it is suggested that the second hole down from
the top
be utilized.
TRAY SETUP:
•
Insert
the stainless steel sign brackets into the slots on the back of the
stainless steel trays. Insert the plastic
signs into the sign brackets for the corresponding tray.
•
Install the supplied rain gauge into one of
the middle trays.
The Rainfall Simulator Unit set up and
operating.
The Rainfall Simulator in action.
CLEAN-UP
PREPARATION:
CLEAN-UP
PROCESS:
Remove the pin from the rainfall mast.
CAUTION: Once the pin is
removed, never leave the mast unattended as it could fall and cause
damage or injury.
WINTERIZATION
PROCEDURE:
Drain
the water from the water tank and lines.
Use enough non-toxic RV antifreeze in the tank to be drawn
through the
pump and out the end of the water supply hose.
RAINFALL SIMULATOR PRESENTATION
GUIDELINE
A very beneficial
aspect of
the Rainfall Simulator is that it can be utilized to demonstrate a
variety of
environmental scenarios. Presentations
can be tailored to deliver focused agendas and share specific
conservation and
environmental information.
Following is the basic presentation agenda that ERMA has been
utilizing. While the degree and depth of
information delivered during a presentation varies depending on the
circumstances of the event, the allotted time, and the targeted
audience, this basic
format is still followed and the key points addressed.
I.
Explanation
of a Rainfall Simulator: What it is, how
it works, and how it is
utilized.
II.
Overview of
the demonstration and lesson.
III.
Define and
discuss watersheds.
IV.
Discuss the
vital
importance of protecting our drinking water and valuable top soil. Define and discuss wells, aquifers, and
the ground water table.
V.
Operate
rainfall simulator long enough that water
run-off from the trays to the jars begins. Discuss
what is happening with each tray and jar as the rain
falls.
VI.
Refer to
photo of
raindrop impacting bare soil. Discuss
the fact that a raindrop falls out of the sky at 15 to 20 mph, and the
effect
this has on the soil. Define soil erosion,
nutrient runoff, and stream sedimentation. (Point
out all of the soil that has splashed onto the sign
and framework around the bare soil tray, while the signs and framework
around
the 100% Crop Residue and Grass trays are clean.) Discuss
how conservation practices reduce water and nutrient
run-off, soil erosion, and stream sedimentation, thereby protecting the
quality
and quantity of our drinking water and preserving the top soil.
VII.
Explain what
each of the
five trays represents.
A.
Tray 1: Bare,
Unprotected Soil. Represents
conventional tillage or a bare construction site. Exhibits
tremendous water run-off and soil erosion. Define
and discuss conventional tillage
or clean till farming.
B.
Tray 2: 30%
Crop Residue. Represents minimum
till farming. Exhibits a reduction
in water run-off and soil erosion over the bare soil tray.
Define and discuss conservation tillage
and minimum tillage.
C.
Tray 3: 100%
Crop Residue. Represents no-till
farming. Protects water quality
and quantity. Demonstrates a
dramatic reduction in water run-off and soil erosion.
Define and discuss no-till farming.
D.
Tray 4:
Grass. Represents a grass
waterway, field border or filter strip.
Protects water quality and quantity. Demonstrates
a tremendous reduction in water run-off and
soil erosion. Define and discuss
filter strips and buffers.
E.
Tray 5: Urban. Represents
impermeable surfaces such as
concrete and asphalt streets, parking lots and walks found in an urban
setting. Exhibits 100% water run-off. Demonstrates the problems of flooding
and pollution. Define and discuss
urban pollution, its causes and sources.
Discuss solutions such as urban detention ponds, water
treatment, proper
waste disposal, proper application of lawn fertilizers, etc.
VIII.
Discuss
benefits
conservation tillage has for wildlife habitat. Show
picture of pheasant in bare field vs. no-till field of
corn stalks. Define "Daily Calorie
Intake".
IX.
Elaborate on
our environmental
responsibility and how we live in a global community.
X.
Question how
nutrient run-off from Illinois could
affect a fishermanÕs livelihood in the Gulf of Mexico. Discuss the geography of the local land
and rivers and where the drainage flows.
Define and discuss eutrophication and hypoxia, and the
consequences for
the Gulf of Mexico.
XI.
Lesson
summary and
affirmation of our environmental responsibility.
TRAY SIGNS:
