What’s all the hype about the pipe?
Pipeline systems for the transport of manure can be a cost-effective system for some farms.
As livestock facilities continue to grow to meet consumer demand, so does the amount of manure at each facility. This may mean manure needs to be moved greater distances from where it is produced. Manure can be transported either above ground via semi tankers, dump trucks, tractors with spreaders, etc., or below ground through manure pipelines. Both above and below ground methods have their risks and rewards.
In a Livestock Poultry Environmental Learning Community (LPELC) webinar titled: Going the distance: considerations for the use of manure pipelines, the topic of below ground manure transport via pipelines was addressed with a short presentation by Glen Arnold from The Ohio State University Extension outlining some of the background information surrounding manure pipelines as well as a panel of experts (Suzanne Reamer, USDA NRCS-MI, Dave Cunningham, Bridgewater Dairy, and Glen Arnold) that held a question and answer session for participants.
Glen’s presentation covered basic information including the volume of manure produced at livestock facilities and the value of manure as a fertilizer source, especially given the current cost of fertilizer prices. The presentation then addressed the logistics of manure pipelines, from the infrastructure to the installation, to the workings of the system. Reduced road traffic is a positive result of installing manure pipelines, which means less road wear and risk of accidents or manure spills. Additionally, underground pipelines can help reduce the mess of manure on roads or mud tracked by equipment onto the roads, allow for the potential of more in-season application of manure, and require less labor due to fewer transportation vehicles needed. Lastly, Glen mentioned some points to consider such as the size of the system and how it accompanies the size of the farm, ownership of the land where the underground manure pipelines would be placed, and what types of regulations may be in place based on individual states. Probably one of the biggest considerations is the cost. Below is a rough estimate:
Initial cost: $158,400 per mile for 10-inch diameter pipe on open ground:
- One mile of 12-inch diameter soft hose: $96,000.
- One mile of 10-inch diameter soft hose: $72,000.
- Does not include cost of needed hose carts.
- Lifespan of equipment is 20 years.
After Glen finished his presentation, questions were answered by the panel of experts. The following is a compilation of that information.
Some of the potential obstacles to overcome when installing a manure pipeline system can include local, state and federal regulations. These regulations differ from state to state, but it is important to consider the different entities that will be involved in the planning process. The governmental and non-governmental entities that you may have to get to know as you navigate the process of installing a manure pipeline in a public right-of-way are your neighbors, township supervisors, drainage commissioners, utility companies or State Department of Transportation staff. Establishing good relationships and then going above and beyond to communicate with these people before, during the planning of, and after the installation process is helpful. Always try to be proactive and not reactive so that if emergencies occur, they are more likely to be resolved in a timely manner. In some cases, manure pipelines are welcomed due to less trucks on the roadways, which helps decrease the amount of odor and road degradation and it can be a cost savings for the farm.
Any time you do groundwork there is the potential for in-field obstacles. Some obstacles you may uncover could include tile that is not mapped and may or may not be hooked into a larger system, soil type and topography may be a challenge, and existing utility lines. Think about contacting your local soil and water conservation office and Miss Dig ahead of time to identify soils and objects such as gas or electrical lines. Manure pipelines should be buried below frost levels, which will depend on your location.
If you are considering installation of manure pipeline, keep in mind basic engineering standards for the practice. According to the NRCS practice standards, which is a nationwide standard (some states may have more regulations or restrictions in place):
- Pressure ratings for pipes need to be 72% of the pipe rating.
- Check valves are required.
- Backflow prevention is required if connected to a well.
- The type of pipe and joints need to be watertight.
- A programmable control panel to indicate, via an alarm, if there is a loss in pressure.
Sediment buildup and scouring can be a real problem in manure pipelines and, therefore, NRCS practice standards recommend a velocity of 3-6 ft. per second. The percentage of sand in the manure may make more of an issue as it is hard on equipment. These are usually pressurized systems in order to deliver the manure to the application equipment at the appropriate rate. On average, pressure ratings of larger pipelines should be around 250 psi near the source. Realize, however, the pressure will drop as you move further away, so if you want for instance, a 250 psi system, the pressure should be around 300 psi to start. Take into consideration the pressure the system’s valves can handle or have pressure relief valves in place. The valves also need to allow for the cleanout device to move through the pipeline during cleanout.
The NRCS Livestock Pipeline design spreadsheet calculates the right pipe size for an installation. The spreadsheet linked in this article above is from Wisconsin while the spreadsheet below is a pipeline thrust design spreadsheet found under the MI NRCS website under engineering. Check valves, double-check valves, or flowmeters should be considered in the equipment list. Though site specific, if a manure pipeline is connected to a well, perhaps for cleaning the manure pipeline, the backflow prevention needs to be a RPZ valve and certified by the American Society of Sanitary Engineers (ASSE), according to the Department of Environment, Great Lakes, and Energy (EGLE) in Michigan. For example: if a pipeline has an uphill flow, the backflow prevention is crucial along with a check valve is recommended to prevent any backflow in the pipeline when the pump stops.
Having a good operation and maintenance plan for the pipeline is key to maximize the useful life of the equipment. If you have a designed system, you should receive an operation and maintenance plan, which will outline the annual or seasonal checks you should do of your specific system. NRCS has an operation and maintenance plan/generic checklist on their field office field tech guide website. Inspection points will include joints, valves, and turns in the manure pipeline. In Michigan, EGLE may also require a visual inspection during the operation of a pumping system be documented.
The spill response plan for manure pipelines is no different than other transfer methods and a plan should be established ahead of a potential spill. Installation is key in prevention of spills because the straighter a pipeline the better and there should be small curves as opposed to 90-degree elbows. With Michigan EGLE, there is not necessarily a spill plan so much as a visual inspection during pumping operations. Additionally, Michigan EGLE does not require secondary containment, but you still need to be smart and have appropriate best management practices in place. If taking a dragline hose through a water body or road culvert, have check valves on both ends of a water crossing and be prepared to act in the event of a spill.
Clean out is a good way to check the pressure and flag any issues with the system. Make sure you have an idea of how to appropriately clean out the manure pipelines or hire someone who does this more often to avoid injuries. This can be done with clean water or rented air compressors and may cost around $10,000. It is more likely to be forgotten due to the manure pipelines being out of sight, so when contracting this work, consider a contract agreement and include a requirement that any commercial applicators using the system must clean the manure pipelines after each use. At a minimum, check the pressure of the system annually.
Michigan State University Extension recognizes that a manure pipeline system is not an option nor will it be beneficial for all farms, but the above information can help those who are contemplating this decision.