senior design project

1. Eastover, SC Community Garden Design in a
Marginalized Food Desert: Soil, Water and
Crop Management for a Sustainable and
Climate-Smart Food Production
Cate Gent, Mary Fran Burnett, Madison Hobgood,
Maddyson Frierson, Bryan Carroll
December 8th, 2022, Clemson, South Carolina

2. Outline
● Introduction
○ Background
○ Rationale
○ Objectives
○ Approaches
● Literature Review
● Materials and Methods
● Results
● Recommendations
● Acknowledgements

3. Introduction

4. Background
● Location: Eastover, SC
● Community garden that has been
struggling to provide enough food for the
town
○ Issues with soil health and water retention
○ Issues with seasonal crops
● 9,000 ft2 of land available for use
○ 5,000 - 6,000 ft2 currently being used
● Recently received a $70,000 grant from
USDA

5. Rationale
● Eastover, South Carolina is located in a food desert where access to
nutritional foods is limited
● Eastover appears to be subject to Environmental Racism, as Eastover is
>95% Black according to the 2020 census, and has a Coal Power Plant and
Paper Mill located near the town, on top of being a food desert
● Therefore, there is a need to design a method to provide nutritious food such
as a sustainable community garden for the community

6. Objectives
The objectives of this project are to:
1) engineer an optimized, low-cost community garden design to maximize crop
yield, soil health, and access to food
2) improve access to nutritious foods in a marginalized food desert through a
design that is sustainable by the local community of Eastover, SC.

7. To achieve these objectives the following tasks have been completed:
Task 1. Perform site visit
Task 2. Perform land survey and hydrologic analysis of site
i. Model topography of site employing survey data
ii. Analyze water infiltration and retention
Task 3. Conduct soil and water sampling of site
Task 4. Assess current crop management and condition
Task 5. Analyze soil and water samples
Approaches

8. Approaches
The following tasks are planned:
Task 6. Design and model a low-cost irrigation and pump system, including with
city water
Task 7. Design and model a low-cost composting system modeled with STELLA
i. Lay out a plan to balance nutrients in soil
ii. Optimize compost percentage to improve water
retention
Task 8. Design a crop rotation and management plan
i. Create a design optimized for food production

9. Gantt Chart
● Made with
Smartsheet
Design a water harvesting plan

10. Food Security
Soil and Water
Health
Crop
Management
Eastover
Community
Garden
Project
Abundance
of available
crops
More
nutritious
crop yield
Sustainable
Community
Garden
Practices

11. Literature Review

12. Literature Review
Composting
● Artursson V, Finlay RD, Jansson JK. 2006. Interactions between arbuscular mycorrhizal fungi and bacteria and their
potential for stimulating plant growth. Environmental Microbiology. https://pubmed.ncbi.nlm.nih.gov/16343316/
○ This paper goes into the improvement of plant growth after interactions with bacteria present in compost
(shown in the figure above)
● Cáceres, R., Malińska, K., and Marfà, O. 2018. Nitrification within composting: A review. Waste Management.
Retrieved October 20, 2022 from https://www.sciencedirect.com/science/article/pii/S0956053X1730795X
○ “Composting is considered an environmental-friendly process involving aerobic transformation of organic
matter and destruction of pathogens and weeds (Rawoteea et al., 2017, Wu et al., 2017). This process is
regarded as a great contributor of promoting circular agriculture (Cáceres et al., 2017) because allows
stabilization of organic waste and production of an organic fertilizer that can be used as a soil conditioner (Sun
et al., 2016), in gardening or as a growing medium in soilless cultures.”
○ This paper discusses the nitrogen cycling within the composting process.

13. Literature Review
Composting
● Hamoda, M., Abu-Qudais, H., and Newham, J. 1998. Evaluation of municipal solid waste composting kinetics. Resources,
Conservation and Recycling. Retrieved October 31, 2022, from
https://www.sciencedirect.com/science/article/pii/S0921344998000214
○ Assumed whole process with one rate constant (0.15/day)
● Sole-Mauri, F., Illa, J., Magrí, A., Prenafeta-Boldú, F., and Flotats, X. 2007. An integrated biochemical and physical model for
the composting process. Bioresource Technology. Retrieved October 20, 2022 from
https://www.sciencedirect.com/science/article/pii/S0960852406003014#app1
○ Extensive model on kinetics of composting

14. Literature Review
Water Harvesting
● Jennings, A. A., Adeel, A. A., Hopkins, A., Litofsky, A. L., & Wellstead, S. W. (2013). Rain barrel–urban garden stormwater
management performance. Journal of Environmental Engineering, 139(5), 757-765.
○ Analysis of a rain barrel implementation strategy that diverts only roof runoff, for which there is a beneficial garden use,
is presented and illustrated with a case study application.

15. Literature Review
Irrigation
● Andersson, L. (2005). Low-cost drip irrigation : on farm implementation in South
Africa (Dissertation). Retrieved from http://ltu.diva-
portal.org/smash/get/diva2:1025520/FULLTEXT01.pdf
○ Water scarcity is linked to food scarcity
○ Assess success of low cost drip irrigation for small scale farms
○ Improved water efficiency, time and labor savings and reduced soil erosion
○ Relevance: Properly train the Eastover garden manager and volunteers on
maintaining the irrigation system
● Rivard, Cary, et al. “Drip Irrigation for Community Gardens .” Research and
Extension | Kansas State University, Kansas State University , Oct. 2014,
https://www.shawnee.k-state.edu/lawn-garden/
○ Drip irrigation systems precisely move water and limit spread of pathogens
○ Disadvantage: water filtration is required to prevent clogging of emitters
○ High pressure drip irrigation suitable for city water outlets (30-50 psi)
○ Relevance: Recommend a filter and high pressure irrigation design

16. Literature Review
Crop Rotation
Griffiths-Lee, J., Nicholls, E. and Goulson, D. (2020). Companion planting to attract pollinators increases the yield and
quality of strawberry fruit in gardens and allotments. Ecol Entomol, 45: 1025-1034. Retrieved from https://doi-
org.libproxy.clemson.edu/10.1111/een.12880
● This study discusses the impacts of companion planting on strawberry crop yield in a garden
● The study found that companion planting increased the amount of pollinating insects in the garden, as well as, the
strawberry crop yield of plants directly beside the companion plant
Kemble, J.M., Meadows, I., Jennings, K., Walgenbach, J., Wszelaki, A. L. (2022). 2022 Southeastern US Vegetable Crop
Handbook. Retrieved from https://content.ces.ncsu.edu/southeastern-us-vegetable-crop-handbook
● This handbook is a reference guide to planting crops in the southeastern United States
● The guide contains state specific species, pests, fertilization, planting, harvesting, etc for various crops

17. Literature Review
Soil
● Ritzema, H. P., Bos, M. G., Braun, H. M., Lenselink, K. J., & Van Aart, R. (Eds.). (1972). Drainage Principles and
Applications (2nd ed.). International Institute for Land Reclamation and Improvement.
○ Water retention and infiltration are important factors to soil health.
○ The water holding capacity of a soil is the range between the field capacity and wilting point. This is affected
by soil type and organic matter content.
○ Infiltration can be defined as the rate at which water flows into the soil through the surface.
● NRCS. (n.d.). NRCS official soil series description view by list. USDA. Retrieved December 1, 2022, from
https://soilseries.sc.egov.usda.gov/osdlist.aspx
○ Both Marlboro and Norfolk soils are well draining soils with moderate to high permeability
○ Coxville soil is a poor draining soil with low permeability.
● Alvarado, D. (2022, April 7). Improving garden soils with organic matter. OSU Extension Service. Retrieved
December 1, 2022, from https://extension.oregonstate.edu/pub/ec-1561
○ “Soils amended with organic matter are a better sponge for water. More water goes into the soil, and less
water runs off the surface. Because surface runoff is reduced, pesticides and fertilizers are retained in the soil
instead of washing into nearby rivers and lakes”
○ “Some vegetable crops, such as rhubarb, are perennials, and many herbs are small shrubs. The deeper roots
of these plants and of annual root crops such as carrots do better in soils amended to a depth of 10 to 12
inches”

18. Literature Review
Soil
● Pitt, R., Lantrip, J., Harrison, R., Henry,
C. L., & Xue, D. (1999). Infiltration
Through Disturbed Urban Soils and
Compost-Amended Soil Effects on
Runoff Quality and Quantity (United
States of America, US Environmental
Protection Agency, Office of Research
and Development).
○ Final infiltration rate of sand,
loamy sand, and sandy loam
soils were found in a range of
0.30 - 0.45 in/hr
○ The field capacity was increased
for some soils with the addition
of compost as shown in Table 4-
1.
○ Compost amendments improved
infiltration rates in all soil types
as shown in Table 4-2.

19. Materials and Methods

20. Site Visit 1
● Site visit
conducted on
September 23rd,
2022
● Collected soil
samples for soil
test with Clemson
Agricultural Lab
● Examined site

21. Site Visit 2
● Site visit conducted on October 14th, 2022
● Conducted double ring infiltrometer test
● Collected soil samples
● Collected water sample
● GPS survey (Juno)
● Observed quality and
types of current crops

22. Geographical Survey of Site
Materials
● Handheld GPS Receiver
(Trimble Juno 3B)
● GPS Data Collection
Software (TerraSync)
● GPS Data Processing
Software
(GPS Pathfinder Office)

23. Geographical Survey of Site
Methods
● Area and point features were collected on the handheld GPS device using
GPS data collection software
■ Areas: total greenspace, current garden space, greenhouse, raised
beds, and mounds
■ Points: around the base of tree and water spout
● The data was processed and corrected in GPS Pathfinder Office

24. GPS Data Correction
● Extraneous points are manually deleted and
excluded from the data
● GPS data can have lots of different errors
based on the conditions during which the
data collection was performed
● Many of these errors can be corrected by
applying the differential correction feature in
Pathfinder Office
● This correction is done by selecting a base
station near the site. This base station has
accurate data from other satellites that
Pathfinder Office uses to compare to the
collected data

25. Water Retention and Infiltration Analysis
Double-Ring Infiltrometer Test
● Materials
○ Double ring infiltrometer
○ Water
○ Ruler
○ Stopwatch
● Methods
○ Double ring infiltrometer was placed in a bed
where crops were growing in order to best
represent the conditions for growth
○ Water was added to the inner and outer ring
until the rate at which the water level
decreased began to slow down
○ The rings were filled with water, and timer was
started
○ The timer was stopped after the water level
had dropped one inch

26. Crop Management
Materials:
● Spatial Analysis
○ GPS Data Collection Unit Trimble Juno Series 3
○ TerraSync GPS Software
Methods:
1. Gather total garden area, raised bed areas, and all permanent points in the garden using GPS
mapping procedures with the Trimble Juno Series 3
2. Observe current garden crop and soil conditions
3. Use obtained data to determine maximum garden spacing and available crop land
4. Research zone specific agricultural data to determine crop list
5. Create a crop rotation and management plan based on garden area, climate, and local crop planting
schedules

27. Composting
● Design a sustainable system that will support the nutrient needs of the garden overtime
● Perform a soil sample test via the Clemson Agricultural Lab to determine nutrient deficiencies and
excessive nutrients, then design a system based on improving the soil quality.
● Develop a batch composting system model using STELLA to understand kinetics of system and
design the system to optimize efficiency and production.
● Ensure a system design will focus on processing compost through the all three stages of
composting.

28. Results

29. Soil Sample Results
Soil Sample Test Performed October 11th, 2022 via the Clemson Agricultural Lab.

30. Soil Survey Info
● Coxville: 11.6%
○ Sandy Loam
○ HSG D
● Marlboro: 43.0%
○ Sandy Loam
○ HSG B
● Norfolk: 45.4%
○ Loamy Sand
○ HSG B
● Via USDA Natural
Resources
Conservation Service
Database

31. Survey Data
Uncorrected
Raw Data
Corrected

32. Survey Data
Section Area
[ft2]
Description
A 16,146 Total greenspace
B 4,306 Current garden
C 215 Greenhouse
D 745 Mulch mounds
E 238 Raised beds
A
B
C
D
E

33. Infiltrometer Test
● The water level dropped 1 inch in 7 minutes
● This infiltration rate is significantly higher than other reported infiltration rates
for similar soil types
● Sandy loam soils have infiltration rates between 0.30 and 0.45 in/hr.
● Visually, the water level had begun to decrease at a steady rate, but more
time may have been required to reach the final rate of infiltration
● There may have been macropores under the surface of the soil
● For the purpose of this project, an infiltration rate between 0.30 and 0.45 in/hr
can be assumed

34. Irrigation system
● Area:4400 sqft (80 ft ✕ 55 ft)
● High Pressure Drip In-Line Irrigation
system with an End Feed Layout
● Water filter is important for city water
lines
● Check valve to prevent city water line
biological contamination
● Solenoid valve to pump water
● Volumetric Water Content Sensor
City Water
Inlet
Water Filter Solenoid
Valve
Check
Valve
`
Solar Panel
Hunter Controller
Volumetric
Water Content
Sensor

35. Irrigation Calculations and Key Parameters
● Soil Survey Information
○ Coxville: 11.6% (Sandy Loam) (D)
○ Marlboro: 43% (Sandy Loam) (B)
○ Norfolk: 45.4% (Loamy Sand) (B)
Wilting Point: 12.9% water
Field Capacity: 30.6% water
● Infiltration rate for sandy loam soils
found to be 0.3 to 0.45 in/hr
Average rate: 0.375 in/hr
● Hunter Industries Drip Irrigation
Design Guide
○ Emitter Flow Rate (D): 1.0 GPH
○ Emitter Flow Rate (B): 0.6 GPH
Overall Flow Rate: 0.82 GPH
● End Feed Layout

36. Irrigation Calculations and Key Parameters
● Emitter spacing (D): 12 in
● Emitter spacing (B): 18 in
Overall Emitter Spacing: 15 in
● Row spacing (D): 15 in
● Row spacing (B): 19 in
Overall Row Spacing: 17 in
● Based on row spacing it is possible to have 38 rows of crops
● Quantity of Emitters within a zone
○ Total Length (in): 11,520
○ Emitter Spacing (in): 15
Quantity of Emitters: 768

37. STELLA Batch Compost

38. STELLA Model Results

39. Water Collection Method

40. Water Collection Design - Rain Barrel Sizing
Roof length: 6.64 ft
Roof width: 4.30 ft
Roof area: 28.52 square ft
Average monthly rainfall in Richland County, SC: 0.29 ft
Volume of roof water that will fill the bucket (roof area x average monthly rainfall):
8.2 cubic ft or 61.35 gallons per month
Days it will take to fill 50 gallon barrel: 24 days

41. Recommendations

42. Irrigation Materials and Pricing
Irrigation Controller Hunter
PRO-HC 12 Station ($420)
Volumetric Water Content
Sensor Hunter Soil-Clik ($114)
Drip Emitters: Hunter -
HE20B100 - Point Source
Drip Emitter, Self-Piercing
Barb ($780 @ $1 each)
Water Filter: One Stop
Outdoor 3/4" Drip
Irrigation/Hydroponics Y Filter
($17)
High Pressure Irrigation Tubing
Supply Tubing (1/2 in), 1000-ft
Roll ($118)

43. Flush Valve: Hunter 17
mm Automatic Flush
Valve Barb ($10)
Irrigation Materials and Pricing
Solenoid Valve 1" 24V
AC Electric Brass ($70)
Check Valve Hunter Grey
3 - 15 GPM 3/4 in. ($9)
PVC Charlotte 1-in x 10-ft
White PVC Pipe ($80)
Air Relief Valve Geoflow
1” MPT kinetic air/vacuum
relief valve ($25)
Sigineer Power 1500W
12V Inverter Charger
($429)
Total: $2,072

44. Irrigation
● Assess the success of the irrigation systems after 1 year though soil quality and crop yield
● Clean the water filter regularly
○ Andersson, L. (2005)
● Properly train all volunteers and employees on drip irrigation management
● Assess crop yield after 3 years to determine if system upgrades are needed
● Each year assess the system for broken parts
● Consider annual flush of irrigation system
○ Biological material and mineral build up
■ Rivard, Cary, et al (2014)
Consult a Hunter Industries
Representative regarding the
End Feed Layout design,
necessary parts and pricing.

45. Energy Collection Method
EcoFlow 220W Bifacial Portable Solar
Panel
$449
● Uses a natural resource to power
Irrigation system
● Assess capacity of solar panel and
battery pack after 3 years
○ Consider moving on to city power
grid

46. Water Collection Materials
$356.99 $131.14 $13.88 (120
in) $43.32 (120 in)

47. Compost Amendment
● In order to bring the organic matter
content up from 4.6% to 10%, 1.5 - 2
inches of compost should be added and
tilled 10 -12 inches deep
○ For an area of 4,500 ft2, 535 ft3 (20
cubic yards) are required
○ For an area of 7,500 ft2, 895 ft3 (35
cubic yards) are required
● Throughout the year a light layer of
compost should be added after
harvesting and two weeks prior to
planting.

48. Tilling equipment can be rented for
$40/day or purchased from Home Depot
for $450.
Maximum tilling depth of 11”
Composting Cost
A cubic yard of compost ranges from $25-
35
● Initial compost layer of 1.5 - 2 inches
○ 4,500 ft2 : $500 - $700
○ 7,500 ft2 : $875 - $1,225

49. Composting System Materials
2X$64.50 $22.99 $12.14

50. Composting System Recommendations
● The waste from the garden should be used as a consistent waste stream to bins.
● An optimal ratio of C:N should be maintained in waste to the compost (around 25-
30:1) to ensure enough nitrogen is available but also to reduce odor.
○ This is done by ensuring browns and greens are both added to the bin (browns are carbon rich, while
greens are nitrogen rich)
● Compost should be ensured to go through all 3 stages of composting (by
checking and logging the temperature, ideally daily).
○ This prevents the growth of pathogens, and ensures maturing of compost
○ For this reason compost should be sectioned in batches as much as possible.
● Local waste streams should be explored to supplement garden waste, which
could have the potential to offset use of synthetic fertilizers and lower the footprint
and cost of the garden, while improving production and overall health of the
garden.

51. Crop Rotation
Source: Clemson Extension
● The full crop list was determined by using
recommendations from Clemson
Extension based on South Carolina
gardening regions and vegetables with
high nutritional value
● These gardening regions take into account
climate and soil composition to plant each
vegetable at the correct time for each
season
● The crop rotation plan was also created for
a 3 year minimum rotation taking into
account soil health to determine which
crops should be planted where each year

52. Crop Spacing
Plant Seed (100-ft row) Spacing Between
row-In row (inches)
Planting Depth
(inches)
Approximate Days
to Harvest
Broccoli ½ ounce 36 x 18 ½ 90-110
Cabbage ½ ounce 36 x 12 3 90-100
Cantaloupe 1 ounce 60 x 24 1 75-85
Collard/Mustard
Greens
½ ounce 36 x 8 ½ 60-70
Cucumber 1 ounce 60 x 12 1 50-60
Garlic - 6 x 6 8 200-280
Kale ½ ounce 36 x 1 ½ 30-55
Lima Beans ¾ pound 36 x 3 1 ½ 65-75
Marigold 2 pounds 7 x 7 ¼ -
Nasturtium ½ ounce 11 x 11 1 -

53. Crop Spacing (Cont.)
Plant Seed (100-ft row) Spacing Between
row-In row (inches)
Planting Depth
(inches)
Approximate Days to
Harvest
Onions ½ ounce 30 x 3 ½ seed 100-120
Peppers - 36 x 18 3 60-70
Potatoes 12 pounds 36 x 12 3 90-110
Southern Peas ½ pound 46 x 4 1 ½ 75-85
Summer Squash 1 ounce 36 x 15 1 50-60
Tansy ½ ounce 35 x 16 ⅛ -
Tomatoes - 60 x 24 4 60-100
Turnips ¼ ounce 30 x 2 ½ 60-70
Watermelon ½ ounce 60 x 60 1 ½ 80-100

54. Crop
Planting
Schedule
● Assuming seeds are
directly sown
● Last spring frost:
March 24th
● First fall frost:
November 9th

55. Garden Design Year to Year
Year 1
Created with: GrowVeg Garden Planner
Source: Farmer’s Almanac

56. Full Garden Design

57. Total Cost Estimate
Our estimate for total costs of recommendations comes out to just under $10,000.
This is well within the $70,000 grant allowing money for maintenance and
upgrades.

58. Food Security
Soil and Water
Health
Crop
Management
Eastover
Community
Garden
Project
Abundance
of available
crops
More
nutritious
crop yield
Sustainable
Community
Garden
Practices

59. Acknowledgements
We would like to extend gratitude to Michael Dantzler, Dr. Christophe
Darnault,The US EPA Representative Jeannie Williamson, Dr. Thomas Dodd and
the community of Eastover to allow us to exercise our engineering skills and
deliver on a positive project.

60. Thank you!