TITLE 35: ENVIRONMENTAL PROTECTION SUBTITLE E:
AGRICULTURE RELATED WATER POLLUTION
CHAPTER II: ENVIRONMENTAL PROTECTION AGENCY
PART 570
DESIGN AND MAINTENANCE CRITERIA REGARDING
RUNOFF FIELD APPLICATIONS SYSTEMS
SUBPART A: INTRODUCTION
Section
570.101 Purpose
570.102 Definitions
SUBPART B: DESIGN CRITERIA
Section
570.201 Runoff Field Application System General Design Criteria
570.202 Conditions for System Utilization
570.203 Planning Considerations
570.204 Component Design Criteria
570.205 Specifications for Vegetation Establishment
570.206 Operation and Maintenance Criteria
570.207 Innovative Designs
APPENDIX A: Design Procedure Outlined
APPENDIX B: Procedure to Estimate Volume of Feedlot Runoff
APPENDIX C: Procedure to Estimate Soil Infiltration Rate
APPENDIX D: Procedure to Determine Slopes
APPENDIX E: Tables to Determine Dimensions of Field Application Areas
APPENDIX F: Recommended Effluent Transport Systems Designs
APPENDIX G: Graph for Determining Flow Rate Over Field Application Area
APPENDIX H: Recommended Distribution Manifold Designs and Junction Box Designs
APPENDIX I: Diagram of Settling Basin Components
APPENDIX J: Sample Design Problem
AUTHORITY: Implementing and authorized by Section 4(m) of the Environmental Protection Act
(Ill. Rev. Stat., 1979, ch. 111 1/2, par 1004(m)), and authorized by Rule 105(a) of Chapter 5 (35 Ill.
Adm. code 502.305).
SOURCE: Adopted at 6 Ill. Reg. 9951, effective August 3, 1982.
SUBPART A: INTRODUCTION
Section 570.101 Purpose
a) The intent of this document is to present design and maintenance criteria for runoff
field application systems (commonly called vegetative filter systems). These
relatively inexpensive systems can be effectively utilized to prevent feedlot runoff
generated by small livestock management facilities from polluting streams, rivers,
and other waters. Small livestock management operations typically do not have the
economic resources necessary to control their feedlot runoff with expensive lagoon-
type zero-discharge systems. The vast majority of livestock management operations
in Illinois are relatively small and, therefore, these criteria add to currently available
procedures of preventing water pollution from livestock management facilities.
b) Runoff field applications systems need attentive maintenance to function properly.
Consistent failure on the part of the operator to maintain a runoff field application
system in good operational condition could result in violations of the Act and
Regulations. Improper maintenance may also result in the facility meeting the
criteria set forth in Rule 203 of Chapter 5. Under Rule 203, the Agency may require
any animal-feeding operation discharging pollutants through a man-made device to
obtain a National Pollutant Discharge Elimination System (NPDES) permit on a
case-by-case determination considering primarily the amount of wastes reaching
navigable waters.
Section 570.102 Definitions
Except as hereinafter stated, and unless a different meaning of the term is clear from its context, the
definitions of terms used in this document shall be the same as those used in the Environmental
Protection Act and Illinois Pollution Control Board regulations, Chapter 3 - Water Pollution (Title
35, Subtitle C, Chapter 1) and Chapter 5 - Livestock Wastes:
“Distribution Manifold” means a device designed, constructed and maintained to provide
uniform sheet flow of settling basin effluent across the width of a runoff field application
area.
“Effluent Transport System (ETS)” means a non-perforated pipe or other device designed,
constructed, and maintained to transport settling basin effluent to a junction box and
distribution manifold.
“Field Application Area (FAA)” means a vegetated area designed, constructed, and
maintained to remove sediment, organic matter, and other pollutants from livestock
management facility runoff by settling, dilution, absorption, adsorption, infiltration,
assimilation, and other processes.
“Junction Box” means a device designed, constructed, and maintained to dissipate the
energy of the anticipated hydraulic jump from the effluent transport system discharge and to
proportionally split the flow to the distribution manifold(s).
“Livestock Waste” means livestock excreta and associated feed losses; bedding; wash
waters; sprinkling waters from livestock cooling; solids removed from settling basins,
lagoons, or holding ponds; precipitation polluted by falling on or flowing onto an animal
feeding operation; and other materials polluted by livestock.
“Runoff Field Application System” means those collective constructions or devices, except
sewers, used to collect, pump, settle, store, and land apply feedlot runoff which include, but
are not limited to, settling basin, effluent transport system, junction box, distribution
manifold, and field application area.
“Settling Basin” means a basin designed, constructed, and maintained to remove settleable
solids in feedlot runoff by gravity.
SI: Soil Infilitration rate (inches per hour).
VR: volume of feedlot runoff to be infiltrated by the field
application area (cubic feet).
QF: Design flow rate (gallons per minute) over the field application area at 1/2 inch
depth of flow for a 2 hour contact time.
SUBPART B: DESIGN CRITERIA
Section 570.201 Runoff Field Application System General Design Criteria
Designing an acceptable runoff field application system shall involve:
a) Meeting the Conditions for System Utilization.
b) Evaluating the Planning Considerations.
c) Meeting the Component Design Criteria.
d) Meeting the Specifications for Vegetation Establishment.
e) Providing the operator with Operation and Maintenance Criteria at least equivalent
to those contained herein, however, with consideration given to the particular
circumstances of each system.
Section 570.202
Conditions for System Utilization
Runoff field application systems shall not be constructed or operated at a livestock management
facility unless the following conditions are satisfied:
a) The livestock management facility confines less than or equal to 300 animal units,
as animal unit is defined in Chapter 5 Livestock Wastes Regulations.
b) No NPDES permit is required for the facility or is currently issued to the facility,
based upon the criteria set forth in Rule 203 of Chapter 5. The Agency will make
this determination for the operator.
c) Sufficient land area with characteristics capable of meeting the design and
maintenance criteria for runoff field application systems, as determined in
accordance with Section 570.204(e) and Appendix E, exists or can be provided by
reasonable means.
d) The runoff field application system is maintained in good operational condition as
provided in Section 570.206.
Section 570.203
Planning Considerations
The following shall be evaluated in planning a runoff field application system:
a) Slopes and soil material, vegetative species, and time of year for proper
establishment of vegetation. Also consider the necessity for irrigation of the field
application area, visual aspects, and other special needs.
b) Location of settling basin.
c) Adequate drainage to insure satisfactory performance.
d) Provisions for preventing or designing for continuous or daily discharge of liquid
waste to the field application area (e.g., provide temporary storage tanks for milking
parlor wastewaters or provide alternate field application areas).
e) Provisions to allow harvesting activities without causing design or vegetative
damage.
f) Provisions for excluding roof water and unpolluted surface water from the settling
basin and field application area.
g) The need to mechanically distribute the flow uniformly across the top of the field
application area.
h) Runoff field application systems designed to be located on soils with infiltration
rates outside the range of 1.0 to 6.0 inches per hour, or that are otherwise designed
or maintained such that the criteria contained herein are not satisfied, shall be
considered innovative designs subject to Section 570.207.
Section 570.204
Component Design Criteria
a) Settling Basin
1) Basin volume shall be 4.5 cubic feet per 100 square feet of area contributing
runoff plus an additional 10% volume safety factor.
2) Ramp slope shall not be steeper than 12:1 (H:V), with 15:1 being preferred.
3) Basin depth shall be 2 to 4 feet.
4) Settling basins located where groundwater tables rise to within 2 feet of the
surface shall be provided with foundation drainage.
5) The settling basin riser pipe should be 18 to 24 inches in diameter with
vertical slots 1 inch by 4 inches high spaced at 120o intervals around the
pipe. There should be 6 slots per foot of height with the bottom row of slots
even with the settling basin floor. To avoid excess clogging, offset or locate
the riser pipe as far as practicable from the inlet of the settling basin and
attach 3/4 inch mesh expanded metal screen cover over the top of the riser
pipe. Provide a ¾ inch mesh expanded metal screen ahead of the riser pipe
so that all runoff entering the riser pipe must first cross the screen. Refer to
Appendix I for a diagram.
6) The settling basin ramp, floor, end-wall, and side-walls should be designed,
constructed, and maintained to withstand normal operation practices
involving power machinery.
b) Effluent Transport System
1) Pressurized effluent transport systems shall be designed by normal
engineering hydraulic considerations including but not limited to static head,
friction losses, flow velocity, and pipe diameter.
2) Gravity flow effluent transport systems may be designed as pipes flowing
full or as open channels. Design velocity shall be 2 feet per second or
greater to prevent solids deposition. Minimum pipe capacity shall equal or
exceed the design flow rate (QF) over the field application area. The design
feedlot runoff volume (VR) shall be calculated by Appendix B. Design flow
rate (QF) can be obtained from Appendix G.
3) Closed pipes used for effluent transport systems shall be provided with some
means of cleaning by rodding or flushing.
c) Junction Box
1) A junction box shall be provided at the intersection of the effluent transport
system and distribution manifold to dissipate the energy of the anticipated
hydraulic jump from the effluent transport system discharge and to
proportionally split the flow to the distribution manifold(s).
2) The recommended junction box design specifications are provided in
Appendix H.
3) The junction box should be provided with a removable cover to allow entry
for maintenance and prevent entry of objects that would interfere with the
operation of the runoff field application system.
d) Distribution Manifold
1) Pressurized distribution manifolds shall be designed by normal engineering
considerations including but not limited to static head, friction losses, flow
velocity, and pipe diameter.
2) Gravity flow distribution manifolds shall be less than 50 feet long each and
at least 2 feet shorter than the width of the field application area.
3) The following must be considered in the distribution manifold design:
A) Construction material
B) Length
C) Capacity
D) Slope (level)
E) Solids removal and cleaning
F) Providing uniform sheet flow
i) Effluent transport system connection point
ii) Capped ends
iii) Orifice or V-notch weir design and spacing
iv) Splash apron such as pea gravel or concrete
G) Location of junction box
4) Recommended designs of distribution manifolds are provided in Appendix
H.
5) Distribution manifolds must be anchored securely while in operation.
e) Runoff Field Application Area
1) The runoff field application area shall be located on gently sloping soils of
moderate permeability supporting a heavy stand of grass vegetation and
designed to operate by overland flow.
2) Slopes shall be shaped to cause applied runoff to flow uniformly across the
design width for the entire length of the field application area.
3) The uniform sheet flow shall move downslope through the field application
area flow length at a velocity that will provide a minimum contact time of
two hours. Appendix E, gives minimum flow lengths needed to provide a
contact time of 2 hours at various slopes.
4) Field application areas shall have a minimum width of 20 feet and a
maximum width of 100 feet.
5) The range of soil infiltration rates specified in the planning considerations
(1.0 to 6.0 inches per hour) insures that the infiltration capacity of the field
application area will equal or exceed the volume of feedlot runoff to be
infiltrated for the 1 year - 2 hour design rainstorm event. The following
equation shall be used for designing the field application area (FAA):
FAA = VR x 12
(2 hours x S1) - 1.69
when: 1.0 < SI < 6.0 inches per hour
FAA in square feet.
VR in cubic feet.
6) The procedures for determining VR and SI are provided in Appendix B and C,
respectively.
Section 570.205 Specifications for Vegetation Establishment
The following specifications shall apply to all runoff field application systems:
a) All trees, stumps, brush, rocks, and similar materials that can interfere with
installing the field application area shall be removed. The materials shall be
disposed of in a manner that is consistent with standards for maintaining and
improving the quality of the environment and with proper functioning of the field
application area.
b) The field application area shall be shaped to the grade and dimensions shown in the
plan or as staked in the field. If necessary, topsoil shall be stockpiled and spread to
the required grade and thickness. Excess spoil shall be disposed of in areas where it
does not interfere with the required flow characteristics of the field application area.
c) All areas disturbed during construction shall be vegetated.
d) To aid in the establishment of vegetation, feedlot runoff shall be prevented from
entering the field application area through the use of temporary diversions until
vegetation is established to a minimum height of 4 inches and 90 percent ground
cover.
e) Immediately prior to seedbed preparation, apply the following minimum amounts of
starter fertilizer per acre:
Nitrogen (N)-120 pounds of actual nitrogen
Phosphorus (P)-120 pounds of P2O5
Potassium (K) - 120 pounds K2O
f) Apply limestone, if necessary, for the species to be grown.
g) Incorporate the required lime and fertilizer and prepare a firm seedbed to a depth of
3 inches. The seedbed shall be free from clods, stones, or other debris that might
hamper proper seeding.
h) Select one of the following mixtures and seed according to the rate shown:
1) Reed canarygrass - 25 lbs./acre
2) Mixture reed canarygrass and tall fescue - 15 lbs./acre of each species.
3) Use of species other than canarygrass or tall fescue shall be considered an
innovative design.
i) Apply seed uniformly at a depth of 1/4 to 1/2 inch with a drill (band seed) or
cultipacker type seeder or broadcast seed uniformly and cover to a depth of 1/4 to
1/2 inch with a cultipacker or harrow. If a drill or cultipacker seeder is used, seed
across the slope or cut channel.
j) Seeding dates shall be either:
1) Early spring to May 15.
2) May 15 to August 1, provided sufficient water is provided for germination
and vigorous growth.
3) August 1 to September 10.
k) Mulch with clean straw using 2 tons of mulch per acre. The mulch must be
uniformly spread over the seeded area.
l) Anchor the mulch by one of the following methods:
1) Press it into the soil to a 2 inch depth by using a serrated straight disk or a
dull farm disk set straight. Cross the slope perpendicular to the direction of
the flow of water, or
2) Apply a netting on top of the mulch and anchor it with staples.
Section 570.206 Operation and Maintenance Criteria
The following operation and maintenance criteria shall apply as best management practices
to all runoff field application systems:
a) Protect the field application area from damage by farm equipment, traffic and
livestock. LIVESTOCK MUST BE FENCED OUT OF THE RUNOFF FIELD
APPLICATION AREA.
b) Avoid damaging the field application area with herbicides.
c) Fertilize the field application area when necessary to establish growth.
d) Harvest when the forage is at the proper state of maturity for maximum quality feed.
No harvesting shall occur after September 15. Use the following guide for cutting
stages and minimum cutting height for the species seeded:
1) Reed canarygrass - cut at early boot stage to heading minimum cutting
height 6 inches.
2) Reed canarygrass - tall fescue mixture - cut at early boot to heading -
minimum cutting height 6 inches.
e) Repair damage caused by erosion or equipment immediately so the runoff field
application system will continue to perform properly. Rills and small channels must
be repaired. A shallow furrow on the contour across the field application area can
be used to reestablish sheet flow.
f) To prevent excess organic solids from entering the field application area:
1) Scrape feedlot regularly; however, do not scrape waste into settling facilities,
but place in separate manure stacking area away from settling basin.
2) Drainage from manure stacking facilities should be directed to settling basin
or contained.
3) Remove solids from the settling basin when 2 to 4 inches accumulate.
4) Scrape lot frequently during early spring. At least once each 7 days is
recommended.
g) If organic wastes accumulate on the field application area and are damaging
vegetation, redistribute wastes.
h) Remove solids that accumulate in the effluent transport system, junction box, and
distribution manifold regularly.
i) Solids removed from runoff field application system components shall be disposed
of pursuant to Technical Policy WPC-2-Design Criteria for Field Application of
Livestock Waste.
j) Periodic soil testing of the field application area is suggested to determine changes
in phosphorus, potassium, and pH levels.
k) Each spring, relevel the distribution manifold and restore the design slope on other
pipes.
l) When vegetation of a kind other than reed canarygrass or tall fescue infests 20% or
more of the field application area, the infested area shall be revegetated as provided
in Section 570.205.
Section 570.207 Innovative Designs
It is strongly suggested that any operator contemplating use of runoff field application systems not
designed, constructed or maintained in accordance with the design criteria contained herein receive
PRIOR approval from the Agency for such system. The Agency will approve innovative designs
should the operator present clear, cogent and convincing proof that the technique has a reasonable
and substantial chance for meeting the requirements of the Act and Regulations, based upon
conservative engineering principles. For further information contact the Division of Water
Pollution Control - Permit Section in Springfield (217/782-0610), or the Agency regional office in
your area.
Examples of innovative designs are:
a) Settling basin designed at less than 4.5 cubic feet per 100 square feet of drainage
area.
b) Settling channel used instead of settling basin.
c) Use of terraces for field application area.
d) Riser pipe designed differently than provided herein.
e) Use of vegetation other than tall fescue or reed canarygrass.
f) Greater than 300 animal units on feedlot.
g) Distribution manifold designed for full pipe flow driven by gravity.
h) Not providing a junction box.
i) Application of materials other than feedlot runoff, rainfall, or milking parlor
washwaters to the runoff field application system (for example silage leachate,
sewage, pesticides, oil, refuse).
j) Use of field application area smaller than provided herein or with less than 2 hours
contact time.
k) Use of soils on runoff field application area with infiltration rates outside the range
of 1.0 to 6.0 inches per hour.
l) Use of field application area widths greater than 100 feet.
Section 570.APPENDIX A
Design Procedure Outlined
1. Collect Site Specific Data
a. Types and Areas (sft) contributing drainage
b. Slope of Field Application Area (FAA) - Appendix D
c. Soil Infiltration Rate (SI) of FAA - Appendix C
2. Calculate Runoff Volume and Total Drainage Area
Working Table in Appendix B
3. Settling Basin Design
4.5 cft/100 sft of drainage area + 10% extra volume
Dimensions from Appendix I
4. Field Application Area Design
FAA = (VR x 12)/[(2 x SI) - 1.69] (square feet)
Dimensions from Appendix E
5. Calculate Flow onto Field Application Area
Flows from Appendix G
or
Qf = (.0026) (FAA) (gpm)
6. Effluent Transport System Design
Recommended Designs from Appendix F
7. Junction Box Design
Recommended Design from Appendix H
8. Distribution Manifold Design
Recommended Designs from Appendix H
Section 570.APPENDIX B
Procedure to Estimate Volume of Freedlot Runoff*
(A) X
(B) =
(C)
Type of
Drainage Area
Area
(Square feet)
Multiplication
Factor (feet)
Runoff Volume (Cubic
feet)
Roof
0.1408
Feedlot
a. Paved or
Concrete
0.0991
b. Earthen
0.0748
* Multiplication factor corresponds to Q of the U.S.D.A. - S.C.S. runoff equation.
Storm event (I) is 1-year, 2-hour storm of 1.69 inches.
Curve numbers (CN) are 100-roof; 95-paved; 91-earthen.
S = (1000/CN) - 10
Q = (I - 0.2S)/(I + 0.8S)
1. Feedlot Runoff Volume = Total of Column (C) (cubic feet).
2. Milking Parlor Washwater =
gallons x.936 (cubic feet - per week)
day
3. Design Runoff Volume (VR) = 1 + 2 (cubic feet).
Use VR (cubic feet) for designing field application area.
4. Total area (sum of column A in square feet) divided by 100 is used to design settling basin.
5. To convert Runoff Volume (VR) from units of cubic feet into equivalent units of gallons,
multiply cubic feet by 7.481 gallons/cubic feet.
Section 570.APPENDIX C
Procedure to Estimate Soil Infiltration Rate
Soil infiltration rate for a runoff field application area can be determined by using:
1. Any of three methods given in EPA Process Design Manual - Land Treatment of Municipal
Wastewater dated October, 1981; Chapter 3.4 - Infiltration Rate Measurements.
2. The following modified cylinder infiltrometer method:
Procedure
A. Preparing the test site
Drive a rigid, leak-proof container approximately 6 inches into the ground taking
care to avoid disturbing the soil as much as possible. This container should be
approximately 2 feet long by at least 10 inches wide, and may be of any suitable
material. A metal pipe is recommended (see FigureC-1).
B. Saturation and Swelling of the Soil
Before conducting the test, saturate the soil for at least four hours, but preferably 8
hours, by refilling the container with clean water as needed.
C. Testing
At the time of the test, adjust the water level to 12 inches above the soil surface.
Allow the water level to drop six inches and then commence measuring the drop in
water level at 15 minute intervals until the water has infiltrated. Repeat part C.
D. Recording Results
Record results of all tests as the total minutes required for the last six inches of
water to infiltrate (minutes/inch). Average the two tests at each site. For example:
Site 1 - Data Recorded
min
inch
min
inch
0
6.0
45
2.5
15 4.5
60
2.0
30 3.5
60
2.0
60 minutes= 60 = 15 min/inch
(6 - 2 inches 4
E. Soil Infiltration Rate
The soil infiltration rate (SI) is calculated at each site:
SI = 36 = inch/hour =
min/inch
Example
SI = 36 - 2.4 inch/hour
15
F. Average the soil infiltration rates from each testing site to calculate the SI value for
the runoff field application area.
These tests must not be made on frozen ground and include a safety factor in Part E to compensate
for inherent inaccuracies in this procedure.
3. Data from a modern U.S.D.A. - S.C.S. soil survey for the county where the runoff field
application system will be installed. Use the Table of Engineering Properties - Physical and
Chemical Properties for Permeability of the surface soil layer as follows:
1. Locate the soil name and map symbol for the field application area on the map
sheets (example - 386A, Downs).
2. On the Physical and Chemical Properties Table locate the surface layer permeability
rate.
Example
Table 15 -- Physical and Chemical Properties of Soils
Soil and map symbol
Depth (inches)
Permeability (in/hr)
386A, 386B
0 - 7
0.6 - 2.0
Downs
7 - 30
0.6 - 2.0
30 - 60
0.6 - 2.0
3. At the surface layer (0 - 7 inches for the example) use the average value of the
permeability range to obtain SI.
Example
SI = 2.0 + 0.6 = 1.3 inches/hour
2
GRAPHIC MATERIAL See printed copy of IAC for detail Figure 1: Cylinder Infiltrometer
Section 570.APPENDIX D
Procedure to Determine Slopes
Slope must be determined at the site of the runoff field application area to use Appendix E. Many
methods are available to determine slope but all methods are based on the fact:
GRAPHIC MATERIALSee printed copy of IAC for detail
The following procedure can be used to determine slope.
1. Obtain a 40 foot length of string or wire with a 25 foot section marked off (if you use nylon,
measure the 25 feet with a steel tape because nylon stretches when pulled taut); carpenter's
line level from a hardware store; a stake; a rod about 8 feet long (an 8 ft. 2 x 4 works well);
a tape measure; a notebook and an assistant.
2. Set up your notes as follows:
Site
run (ft)
rise (ft)
1 0 0
1-2
25
2-3 25
3-4 25
etc.
Refer to Figure D-1. 3.
3. Stake one end of the string at point 1 and attach the other end to he rod so that there is 25
feet between the stake and rod, and he string can slide up and down the rod. With the string
taut, evel the string in the center using the line level and record the rise at point 2 in your
notes by measuring the string height at the rod.
4. Repeat step 3 all the way down the field and calculate the slope by:
Slope =A(100)(% or ft/100ft)
B
5. the % slope for Appendix E.
GRAPHIC MATERIAL See printed copy of IAC for detail
Figure D-1: Field set-up for determining slope
570.APPENDIX E
Tables to Determine Dimensions of Field Application Areas
Figure E1: How to Use Table E-1.
GRAPHIC MATERIAL See printed copy of IAC for detail
1. Enter at slope of field application area from Appendix D.
2. Read down column and find corresponding length of field application area.
3. Continue down column stopping at area closest to that previously calculated for your site.
4. Read left to find width of field application area.
Table E-1 Runoff Field Application Areas (square feet).
Slope (%)
Length (ft)
0.5
300
0.7
375
1.0
425
1.5
525
2.0
600
3.0
750
4.0
800
20 6,000
7,500
8,500
10,500
12,000
15,000
17,000
25
7,500
9,375
10,625 13,125 15,000 18,750
21,250
30
9,000
11,250
12,750 15,750 18,000 22,500
25,500
35
10,500
13,125
14,875 18,375 21,000 26,250
29,750
40
12,000
15,000
17,000 21,000 24,000 30,000
34,000
45
13,500
16,875
19,125 23,625 27,000 33,750
38,250
50
15,000
18,750
21,250 26,350 30,000 37,500
42,500
55
16,500
20,625
23,375 28,875 33,000 41,250
46,750
60
18,000
22,500
25,500 31,500 36,000 45,000
51,000
65
19,500
24,375
27,625 24,125 39,000 48,750
55,250
70
21,000
26,250
29,750 36,750 42,000 52,500
59,500
75
22,500
28,125
31,875 39,375 45,000 56,250
63,750
80
24,000
30,000
34,000 42,000 48,000 60,000
68,000
85
25,500
31,875
36,125 44,625 51,000 63,750
72,250
90
27,000
33,750
38,250 47,250 54,000 67,500
76,500
95
28,500
35,625
40,375 49,875 57,000 71,250
80,750
100 30,000
37,500
42,500 52,500 60,000 75,000
85,000
Section 570.APPENDIX F
Recommended Effluent Transport Systems Designs
Type Mimimum
Flow*
of gpm)
Minimum
Slope (%)
Design
Velocity (fps)
Matrials Dimensions
Diagrams
GRAPHIC
MATERIAL See
printed copy of
IAC
Pipe 179 0.5
2
PVC 6” diam
332
0.4
2
PVC
8”
diam
Open Channel
Rectangular 224
0.33
2
Concrete,
Wood,
Asphalt,
Aluminum
6” x 6”
Trapezoidal 224
0.37
2
Concrete,
Wood,
Asphalt,
Aluminum
b = 6”
S = 2:1
d = 3”
Section 570.APPENDIX G
Graph for Determining Flow Rate Over Field Application
GRAPHIC MATERIAL See printed copy of IAC for detail
Section 570.APPENDIX H
Recommended Distribution Manifold Designs
GRAPHIC MATERIAL See printed copy of IAC for detail
Section 570.APPENDIX I
Recommended Junction Box Designs
GRAPHIC MATERIAL See printed copy of IAC for detail
Section 570.APPENDIX J
Diagram of Setting Basin Components
GRAPHIC MATERIAL See printed copy of IAC for detail
570.APPENDIX K
Sample Design Problem
A livestock producer had 300 head of feeder cattle on a concrete feedlot (see Figure 1) and wanted
to install a runoff field application system to control feedlot runoff which entered a nearby stream.
The facility met the Conditions for System Utilization set forth in Section 570.202 and the runoff
field application system was designed by following the procedure in Appendix A.
1. Site Specific Data
A. From Figure 1 and Appendix B:
Concrete Feedlot Area 20,038 sft.
(0.46 acres)
Roof Area 4,792 sft.
(0.11 acres)
All other drainage was diverted from the feedlot and field application area with
gutters, curbs, and berms.
B. From the procedure in Appendix D, the slope of the field application area was 1.0%.
C. From the Soil Survey for the county the soil infiltration rate (SI) of the field
application area was 2.0 inches/hour using the procedure in Appendix C (#3).
2. From Appendix B, runoff volume was calculated.
Roof 4,785 sft. x 0.1408 = 673.7 cft.
Feedlot 20,037 sft. x 0.0991 = 1985.7 cft.
Design Runoff Volume (VR) = 2660 cft.
From Appendix B, the total drainage area was calculated.
20,037 + 4,785 = 24,822 square feet
3 Settling Basin Design
The total settling basin volume was calculated as provided in Section 570.204(a)(1).
24,822 sft. x 4.5 cft.= 1117 cubic feet
100 sft.
1117 cft. x 10 = 112 cubic feet
Total Volume = 1229 cubic feet
From Appendix I, the settling basin dimensions were calculated after choosing 3 feet
settling basin height (h), 12 feet width (b), and 15:1 slope.
L1 = 3 x 15 = 45 feet
V1 = (1/2) (12 x 3 x 45) = 810 cft.
V2 = 1229 - 810 = 419 cft.
L2 = 419/ (12 x 3) = 11 feet, 8 inches
Round-off L2 to 12 feet.
Foundation drainage title were not needed as the soil survey indicated the
groundwater table did not rise above 5 ft. depth.
A 24-inch diameter riser pipe was provided pursuant to Section 570.204 (5) and
concrete was chosen as the settling basin construction material.
4. Field Application Area Design
The field application area was calculated using Section 570.204(e)(4).
FAA = 2660 x 12 = P31,920 = 13,818 sft.
(2 x 2.0) - 1.69 minimum area needed
Appendix E was used to determine the dimensions of the field application area using
the next larger sized area of 14,875 sft.
Slope 1.0%
Length 425 feet
Width 35 feet
FAA 14,875 sft. (0.34 acres)
5. Cacluate Flow onto Field Application Area
The flow onto the field application area was determined using Appendix G as being
approximately 40 gpm.
A more accurate calculation was made as follows:
Qf = (0.0026) x FAA
Qf = (0.0026) x 14,875 sft. = 38.7 gpm
6. Effluent Transport System Design
A pipe was chosen to transport the settling basin effluent to the distribution
manifold and was designed using Appendix F at the 179 gpm criteria (since this pipe
design could handle 38.7 gpm).
Slope 0.5 %
PVC non-perforated pipe
Diameter of pipe - 6 inches
7. Junction Box Design
A junction box was constructed to the specifications provided in Appendix H.
Adjustable slots were included in the drop boxes to compensate for frost heaving of
the junction box in the future.
8. Distribution Manifold Design
The distribution manifolds were designed using the 1/2 Pipe criteria at 150 gpm as
provided in Appendix H.
Length of each manifold = 35 feet - 2 feet= 16.5 ft.
2
An 8-inch diameter PVC pipe (17 feet long) was purchased and cut in half down the
pipe length to provide 2 manifolds each 4-inches deep. Each manifold had 6 inches
removed to provide the required length of 16.5 feet.
Tin snips were used to cut V-notch weirs 12 inches apart on center on one side of
each manifold with each notch cut 1.5 inches wide and 2.5 inches deep.
The two distribution manifolds were placed in the previously installed junction box
(the junction box was located in the center of the field application area width). Caps
were provided over the outside end of each distribution manifold and 1/8 - inch wire
staples were used to anchor each manifold at 5 foot spacings.
A 1-foot wide pea gravel splash apron was provided below the V-notch weirs over
the length of each manifold.
GRAPHIC MATERIAL See printed copy of IAC for detail
Figure K-1: Sample Design Problem