Drainage Water Management
Taking Tile to the Next Level
Part 1 of a 2 part series
In agricultural communities across the country there continues to be shift in thinking about the on-farm practice of drainage (think tile) to water management. Every season, more and more producers across the state of Indiana are implementing more than pattern tile systems and moving toward fully controlled Drainage Systems – giving farmers control over the amount of sub-surface water in their fields at any time of the season.
During times of the year when farms don’t require as much water, farmers can manage the amount that is held in the subsoil. With a Drainage Water
Management (DWM) System, landowners get all of the benefits of getting rid of the excess water when it’s not needed as well as draining no more water than necessary from the field. Additionally, with DWM systems, there is a reduction in nutrient runoff reducing nitrate pollution to waterways, ponds, and our interconnected water systems.
- With controlled drainage, farm fields achieve full drainage before getting out for field operation.
- During the growing season, drainage can be reduced to keep critical moisture in the soil.
- In the fallow (post-harvest), productivity & conservation benefits combine when drainage can be turned off completely to retain the water soluble nutrients in the soil profile and reduce run-off.
Two leading factors that influence yield and productivity are excess water and the lack of water during critical plant growth periods. Research at universities such as Purdue, Minnesota, and Kansas are producing results that show significant increases in yields and reduction in nitrate levels in drainage water. Chris Freeland, the Ag Drainage Project Manager at Dwenger Excavating told us that, “DWM has the capacity to bump yield several percent when managed properly.” According to a study conducted by Purdue University, nitrate level run-off can be reduced by an average of 20% annually.*
Drainage Water Management promises a lot of benefits, but it’s not meant for every farm or field. “Until you know what the challenges are for your field, and have made a solid plan, you can’t justify an investment in DWM,” added Freeland. In her ten (10) years of experience in soil and water management, Chris has helped design pattern tile and DWM systems for landowners across West Central Indiana and as more and more people look to farm smarter in response to rising input costs, Freeland recommends the following to anyone considering DWM on their own farms.
Identify Your Goals & Objectives
Whether the end result you seek is based on productivity gains, water conservation in your soils or if you are worried about potential legislation regarding nitrate runoff, your goals should be identified upfront to ensure the system meets your needs and budget.
Create a Plan
Once you’ve identified the benefits you want to achieve in a DWM system, the local NRCS office can help with a Conservation Activity Plan (known as a CAP 130). This plan is used to determine feasibility, action steps, cost analysis, and ROI. Those interested should contact their district conservationist to get the ball rolling. In many cases, NRCS/EQUIP funding is available to hire a certified technical services provider to create the plan for you.
Economics / ROI
Once you have completed a DWM CAP 130 plan with the NRCS, it’s time to look at the economics. How well can your investment in DWM be justified in yield gains, input savings, and conservation benefits? There are higher upfront costs associated with a DWM system, but when yield is considered a multiplier over time, the economic feasibility for your fields will become much clearer.
According to the USDA’s Indiana County Acres Summary**, nearly 80,000 acres or 30% of the farms in Benton County are ideally suited for DWM, with over 40% of the cropland acres in White County and approximately 18% of Tippecanoe County farms. While those numbers seem large, there are limitations to DWM including higher upfront costs, having the right soil profiles, slope, and topography. Regardless of your goals, there remains a lot of opportunity to consider how Drainage Water Management could affect your farming operation.
Pros of Drainage Water Management
- Water Conservation, helpful in times of drought
- Improved Water Quality downstream
- Yield Multiplier / Production Benefits
- NRCS/EQUIP Funding available
Cons of Drainage Water Management
- Higher upfront cost
- Must have the right soils
- Topography / Slope limitations
It’s worth noting that Drainage Water Management and Subsurface Drip Irrigation (SDI) is not the same thing. SDI is an extension of DWM and once a DWM system is in place, you’re really just a few steps away from accomplishing Subsurface Drip Irrigation, a topic we’ll drill into in part 2 of this series.
Drainage Water Management and Subsurface Drip Irrigation have become very compelling production practices for the farmer of today and tomorrow. With potential for long-term yield boosts in both good and bad weather years, the risk vs. reward of these investments continue to paint a picture that as Chris Freeland puts it, “is more about farming smarter, keeping one of your biggest assets (your soil) as healthy as possible, and developing management practices that have the potential to boost productivity year over year.”
About the Author
The Back Forty is regular column written by Published Author, Purdue Graduate and Farmland Broker Johnny Klemme. His reporting, interviews with Ag Experts and more can be found at www.PrairieFarmland.com/blog
*Drainage Water Management Impacts on Nitrate Loads in Indiana. – Dr. Jane Frankenberger, Roxanne Adeuya, , Nathan Utt, Eileen Kladivko, Laura Bowling, Agricultural & Biological Engineering, Purdue University, 2009 – 2012.
**Indiana Cropland Suitable for Drainage Water Management. – USDA Central National Technology Support Center, 2011.
Illustration Credit, Dr. Jane Frankenberger Purdue University.