Manure management is inescapable when you are a dairy farmer. And dealing with the more than 20 gallons of manure and urine each cow generates every day requires a significant investment by farms of all sizes.
Manure systems are multifaceted and often feature a combination of factors to address, including animal type (cows and/or heifers), bedding choice, facilities, collection system, and one or more manure processing or storage structures and equipment. Plus, manure management is often accompanied by challenging tradeoffs between environmental, economic, community and business priorities. As a result, manure management systems – the entire system of various components (handling, storage and application), which may or may not be interchangeable – involve a balance of these tradeoffs.
How can a dairy farm ensure wise use of resources and optimize return on manure system investments, especially those that have adopted sand bedding?
Start at the start
The simplest way forward is to assess the current state of your system. Begin working to solve current, specific pain points, such as sand recovery. Using this snapshot perspective helps avoid getting caught up in the details and prevents decision paralysis while setting the stage for potential growth and success.
For example, a sand-bedded dairy’s immediate concern may be the increasing cost of sand, the rising cost of sand delivery or even sand availability. In this case, it makes the most sense to explore how to best capture and recycle sand from manure. If a 1,000-cow dairy spends $18 per ton of sand and uses 50 pounds per cow per day on average, it costs $164,250 a year for sand purchases. With a sand separation system that conservatively recovers up to 90% of sand for reuse, the dairy can save $147,825 a year in capital expenses by recycling their sand bedding. And the farm only needs to source 10% of the bedding they previously needed.
An immediate sand-recovery focus also makes sense for dairies concerned about excessive sand buildup in manure storage facilities, adding to expenses as well as increasing wear and tear on equipment and affecting field soil quality. Dairies often see a quick return in time and manure hauling savings when sand is removed before it gets to storage facilities. For example, it is not uncommon for custom applicators to charge more to deal with sand-laden manure. At $0.025 per gallon, that is an additional $25,000 per every 1 million gallons.
Additionally, removing sand from manure results in a more homogenous material in lagoons that is desirable for field application. Farms no longer must bring water back from lagoons to support the mixing and application process. Ultimately, dairies have a well-mixed product that can go into storage, be land-applied as needed and can help maximize nutrients for field crops while lowering fertilizer expenses.
When done correctly, maximized sand recovery not only can help the dairy reclaim some of that bedding cost immediately, but the new system also aids with lagoon management and nutrient management goals.
Investment vs. expense
Manure management must always be considered as part of the greater whole to maximize effectiveness and recoup your investment. Once you identify your priority pain point, you can consider how a change would impact other factors, such as electricity, labor, maintenance, depreciation and additional building costs. In the Midwest, equipment must be protected against wintry conditions, and it is essential to keep manure from freezing so it can be processed 24-7.
Data from dairy farms in Iowa suggest that the net cost to store and handle manure per cow ranges from $95.39 for two-stage sand systems to $161.56 for mattress/waterbed systems. All told, the total storage and handling costs per cow ranged from a low of $242.39 for solid systems to $349.50 for mattress/waterbed systems.
Knowing these details helps guide the next steps and visions for the future, such as expansion plans, desired changes for manure handling and labor requirements.
Uncovering savings
The more you holistically consider these factors at the front end of your plan, the more longevity, cost-effectiveness and faster return on investment are built into your system. Case in point, following an upgrade to your manure management system, maintenance costs and labor needs may change.
A better, more effective layout and more access to the equipment make it easier to operate and maintain. Installing a flume or making other changes to the way a dairy handles manure can save hours in the barn. Inherently, somebody must manage the system. But saving hours scraping manure means your team can put those hours toward doing something else on the dairy – whether that might be leveling stalls to improve cow comfort, more thoroughly cleaning pens, removing sand from the sand building or putting their skills to work elsewhere on the farm. Dairies have documented that by putting in a flume rather than turning manure, an employee was in a skid steer up to 10 fewer hours than when the farm used its previous methods, allowing the employee to do multiple other tasks rather than scraping the barn.
Ideally, manure system components build on each other and are part of a longer-term vision. For instance, sand separation and recycling solutions must be precursors to discussions and implementation of anaerobic digester technology. By starting with one identified challenge (snapshot), you can map out an efficient path for future growth and improvements.
Dairies can begin with sand separation then add system components, such as a dewatering screen and bedding dryer, and incorporate anaerobic digester technology as their management and goals evolve. Of course, it is easier to plan for and incorporate equipment in new facilities, but even then, leave your options open for future technology advances.
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