This document discusses how drainage water recycling projects can help address challenges facing agriculture by reducing nutrient pollution and increasing crop yields. Such projects capture nutrient-rich drainage water in constructed ponds during rainstorms and drought periods and use it to irrigate crops. Demonstration projects show corn and soybean yields increased by 19% and 12% on average with irrigation. These dual benefits make drainage water recycling a promising strategy for sustainable agriculture and water quality.

1. Innovative Agriculture:
Meeting the Needs of a Growing Population and Adapting to
Climate Change using Recycled Drainage Water for Irrigation
to Increase Crop Yields while Reducing Nutrient Pollution
Stephanie Singer
Outreach Education Specialist

2. The Mission of The Nature Conservancy
is to conserve the lands and waters on
which all life depends

3.  Agriculture in the Western Lake Erie Basin is under pressure to reduce nutrients, specifically dissolved phosphorus,
from leaving fields and fueling harmful algal blooms.
 Weather extremes, such as intense rain storms, lead to large pulses of nutrient rich run-off to fill waterways.
 There are longer periods of drought throughout the growing season impacting crop yields.
 Drainage water recycling projects take nutrient rich water from drain tile or nearby water sources during periods of
intense flow to a constructed pond.
 The landowner will then use this water during dry periods to irrigate crops and significantly increase yield.
 Demonstration projects will allow this practice to be evaluated for more widespread adoption as a dual win for
benefits to agriculture and water quality.
Water Management as a Strategy to Reduce
Nutrient Pollution

4. Western Lake Erie Basin
 2,000,000 residents
 5,000,000+ farmed acres
 11,000 square miles
 3 states, 30 counties, 2
countries
 $3+ Billion Ag Industry
 $11+ Billion Tourism
Industry
 119,000+ jobs
 World-class fisheries
and bird migration
zone

5. A history of land drainage and channel
modification…

7. Harmful Algal
Blooms
Point sources – non CSO (estimates from US EPA,
2005-2015)
Point sources – CSOs (estimates from US EPA)
Septic systems (~40% of septic systems
contributing)
Non-farm fertilizers (assuming all fertilizers reach
streams)
Agriculture and legacy sources (calculated as the
average of load at Waterville gage station
between 2005-2015 minus all other sources)

13. HOW DOES IT
BENEFIT WATER
QUALITY?
 Because tile drainage can have high
concentrations of nutrients, recycling the
nutrients contained in the drainage water back
into the field where the crop can use them
provides a water quality benefit.
 A system that captures and stores 3
inches of drain flow, with a concentration
of 15 parts per million (ppm) nitrate-N
and 0.5 ppm phosphorus, can prevent 20
lbs. of nitrate and 0.6 lbs. of phosphorus
per acre from reaching downstream
waterways. If this system drains 160 acres
it could reduce downstream loads by
more than 800 lbs. of nitrate and 27 lbs.
of phosphorus/year.
 Natural removal processes present in the pond
itself, such as settling and denitrification.
 At one of the Ohio sites, wetland field
tests showed that natural processes could
remove 28% of the nitrate present in the
drainage inflow

14. HOW LARGE DOES THE POND NEED TO BE?
 Ponds can be sized based on either the desired irrigation water
availability, or amount of drain flow and runoff to be stored.
 Irrigation needs are typically calculated based on the difference
between crop water needs and the water provided by precipitation
that is stored in the soil root zone.
 EX: corn uses approximately 18-20 inches of water during the 5-
month growing season, while precipitation in the growing season
ranges from 14-24 inches. Supplemental irrigation that provides 3-
5 inches of water could significantly improve crop yields
 For initial planning purposes, the minimum pond volume needed can
be estimated by multiplying the number of inches of irrigation water to
be stored by the area of the field.
 PV = FA * ID
 where PV = pond volume, FA = field area, and ID = irrigation depth.
 EX: the pond volume needed to provide 3 inches of irrigation(0.25
inches) water to 80 acres is 20 acre-feet. Final pond design would
need to account for all inputs (e.g., drainage, runoff, groundwater)
and losses (e.g., irrigation or other withdrawals, seepage, and
evaporation).

15. Pond area needed for this pond volume
depends on the average depth
PA = PV/PD
where PA=pond area and PD=pond
depth.
For example, the pond area and pond
depth for a pond volume of 20 acre-
feet could be any of the following:
• 20 acre area with an average
depth of 1 foot
• 4 acre area with an average
depth of 5 feet
• 1 acre area with an average
depth of 20 feet
HOW LARGE DOES THE POND NEED TO BE?

18. HOW MUCH CROP YIELD INCREASE CAN BE
EXPECTED FROM DRAINAGE WATER RECYCLING?
 The average corn yield increase was 19%, with a
29% increase in dry years
 The average soybean increase was 12%, with a
25% increase in dry years
 More efficient use of agricultural land

19. Platter Creek Proposal

20. Platter Creek Proposal
 319 Grant Budget included $150,00 for earthwork
and $54,000 for pumps and connection to
irrigation system. $20,000 for a phosphorus filter
bed
 Embankment: Dam Permit required? Not if
embankment is 6 feet or less OR 10 feet or less
with less than 50 acre foot of storage.
 19 feet deep (9 foot below grade with a 10 foot
embankment)
 44 acre foot of storage
 9 inches of irrigation per year for the 58 acre
field (14 million gallons of water to pump per
year with a 1,000 gallon per minute pump = Run
time is 20 days)
 Soil Boring tests results reveled deep sand veins
which increased the earthwork budget beyond
justification

21. Lenawee, MI Project: Brian Goetz Farm
Closed Loop Drainage and Sub-Irrigation System:
 The project is designed to harvest the drainage water from a 100-acre field that is dedicated to growing
corn, soybeans and wheat.
 Storage reservoir that is 16.5 feet deep and 580 feet long by 360 feet wide. It will store 2.4 million gallons
of water.
 The closed loop system will mitigate most of the Nitrogen and Phosphorus loss found in subsurface
drainage systems. From past research on similar soils in Northwest Ohio the system will save about 32
lbs/acre of Nitrogen and .32 lbs of P/acre that annually is discharged through a subsurface drainage system
outlet.
 NRCS standards and specifications which include: 378-Pond, 342-Critical Area Treatment, 449-Irrigation
Water Management, 553-Pumping Plant, 554-Drainage Water Management, 587-Structure for Water
Control and 606 Subsurface Drainage System.
 The Michigan Land Improvement Association will be working with the Lenawee Conservation District on a
two-day field day where members of the association will be installing subsurface tile in the 100-acre field.
 There will be presentations in the field all day long on drainage water management, subsurface drainage
systems, sub-irrigation design systems, nutrient management and cover crops.

22. Closed Loop Drainage and Sub-Irrigation
System: Brian Goetz Farm
Item Unit Units Needed Cost/Unit Subtotal Cost
Subsurface drainage
20 foot spacing
Ac. 100 1500/ac 150,000
Storage Pond Cubic Yards 52,000 3.50/yd 182,000
Structures for water control EA 14 2,000 28,000
Pumping Plant EA 1 4000 4,000
5 HP pumps EA 2 7000 14,000
Miscellaneous % of total 5% 18,500
Total 396,000
All the funding for the project will be used to assist in the excavation of the storage pond. The
landowner will be paying for all the subsurface drainage system with help from the Michigan
LICA. The Lenawee Conservation District has an additional grant for drainage water
management and will assist in the funding of the structures for water control.

23. Systems Approach
In-the-Field
Nutrient Sources
nutrient
management &
soil health
Edge-of-Field
Delivery
pathways
practices to
manage farm
runoff
Beyond-the-Field
Natural
Infrastructure
streams, floodplains
and wetlands
Providing Food
and Water
Sustainably

24. Water Management as one tool
 In an intensively tiled and drained system, water management
is increasingly becoming more important as weather patterns
change and we work to decrease nutrient from entering the
system
 Drainage Water Recycling is one of many tools to be used in
combination to increase the sustainability of agriculture while
decreasing nutrient pollution
 The Nature Conservancy in Ohio
facebook.com/groups/OhioTNCAgriculture
Nature.org/Ag
Stephanie.singer@tnc.org
Thank You!