One of the biggest challenges—and opportunities—in livestock operations is how to make the most of the nutrients in manure. At NutraDrip, we’ve been walking alongside growers as they take advantage of these nutrients through subsurface drip irrigation (SDI).
From Lagoon to Drip System
Todd Rokey, a local corn and soybean farmer in the Sabetha, KS area, already had a drip system installed and came to us with a big question:
“Can I put manure through my drip system?”
He had a hog lagoon connected to his finishing barns and wanted to use the nutrient-rich manure in a more efficient way. What started as a basic pump setup has evolved significantly. Today, we use a self-cleaning, floating Riverscreen system with a 120-mesh filter that pulls liquid off the top of the lagoon while leaving solids behind. For lagoons with less than 2% solids, this is a simple and reliable solution. When solids exceed 2%, we need to take things a step further.
Riverscreen on Todd’s lagoon
The Heavy Lifting: Deep Pit and Dairy Manure
When producers with deep pit hog barns or dairies—where solids are greater than 2%—asked us to help them make their manure SDI-compatible, we had to innovate further. We partnered with a company from Italy that had experience with high-solid manure.
Here’s how the system works:
- Vertical screw press: This is mounted on the front of the trailer and removes large solids—hair, corn hulls, etc.—which are collected separately.
- Micro filter: The liquid then passes through a 25-micron screen—about the size of a white blood cell. For context, that’s much finer than the 130-micron sand media filters used in most drip systems.
Once it passes through this system, the liquid is clean enough to go straight to a drip irrigation system without clogging it. We’ve tested this on various types of manure—swine, dairy, and others—and this system worked well for all of them.
Mobile manure separation unit showing separator.
Microfilter on mobile manure separation unit.
Image Credit: Visual Capitalist – “Visualizing the Relative Size of Particles”
Source: https://www.visualcapitalist.com/visualizing-relative-size-of-particles/
Managing Phosphorus: A New Tool for a Growing Concern
For many livestock producers, phosphorus levels in fields are becoming a limiting factor. Regulations often restrict how much phosphorus can be applied, especially in areas with repeated manure applications.
The separation process helps here in a big way:
- Nitrogen and potassium stay in the liquid form and are easily delivered through drip.
- Phosphorus, however, binds to solids and is removed in the filtration process.
After the micro filter, we’ve seen:
- Up to 90% phosphorus reduction in dairy manure.
- 30–50% reduction in swine manure.
This means phosphorus is now in a dry form, which can be stored, transported, or even sold—giving producers flexibility and compliance options they didn’t have before.
Dry solids coming out of the separator.
Exploring New Frontiers: Starter Fertilizer Trials
With this separated manure, growers started to wonder: What else can we do with it?
So, a few trials were ran using the liquid manure as a starter fertilizer for corn, applying it at 5, 10, and 15 gallons per acre.
Results showed:
- Improved emergence at all three rates.
- In one mixed-product field trial, a farmer saw a 17-bushel yield increase—though we can’t pinpoint how much came from the manure since it was applied with other products.
This year, more structured testing is planned across 10 to 12 farms. The economics are compelling: at just 10 cents per gallon, applying 10 gallons per acre only costs $1/acre—compared to $15/acre with most commercial starter fertilizers.
We’ve also seen producers experiment with foliar applications and Y-drop treatments using clean liquid manure. However, a fair warning—our process doesn’t remove the smell. It’s still manure!
Ready to Get More Out of Your Manure?
If you’re dealing with livestock manure and want to explore new ways to manage nutrients or reduce phosphorus concerns, reach out. Whether you’re interested in drip application or starter fertilizer trials, we’d love to help you make the most of what you’ve already got.
Netafim has successfully implemented this approach with dairies in California, dubbing the system SDI-E, and Kurt has expanded on that research for the Midwest. He’s developed a low-cost operating system that offers confined animal feeding operations a simple, effective solution for managing livestock waste.
Other Similar Blog Posts:
Unlocking New Potential for Growers With NutraDrip
Permanent Manure Separation at Research Facility in Eastern Missouri
Yes, lagoon water can flow through drip tape by Farm Progress
