Manure spills are typically caused by the mechanical failure of equipment or strictly an accident, much more so than mere negligence, according to recently released information from U.S. extension agents. They can also be due to improper application or poor management of storage facilities. With proper planning and prevention, such a spill can be dealt with quickly before the 5 o’clock news is at your door.

Four extension agents from across the country recently reviewed the common causes of spills, how to plan for an emergency and how to handle the situation if it should happen.

What causes manure spills?

Researchers in Iowa, Ohio and Wisconsin have been studying the root causes of manure spills for the last two decades. Kevin Erb, conservation training coordinator at the University of Wisconsin, recently shared the studies’ findings.

More than 300 cases in Iowa from 1992 to 2002 had equipment failure (24 percent) and storage overflow (24 percent) as the two main causes in spill events.

Ohio only focused on liquid manure applied to cropland and not storage incidents. It found that an incident is more likely to occur in the fall (41 percent) than any of the other seasons. Excess rain and saturated soils, as well as applicator error, were factors in more than half of the incidents.


In Wisconsin, the number of incidents reported increased from 40 to 95 a year between 2005 and 2009. Erb attributes this not to there being more incidents, but to more incidents being reported. “The key mantra we use is ‘an accidental spill is not illegal – failure to report a spill is,’” he says.

The spills in Wisconsin occurred most on-farm (44 percent) versus transportation (27 percent) and land application (29 percent). The main reason for on-farm incidents was storage overflow (44 percent), mostly in August and April as farmers waited too long to get out in the fields, Erb believes. Leaks in the storage vessel or mechanical failure accounted for 40 percent of the on-farm spills. When it comes to transportation incidents, operator error was involved 48 percent of the time.

Emergency action plan

Having an emergency plan in place will help in dealing with the spill quickly, minimizing additional damage. Yet, Tommy Bass, livestock environment specialist, Montana State University, says planning is a difficult sell because the immediate benefit is not noted. However, when it is needed, having a plan is invaluable. Not only is having an emergency plan a good idea, it is required in most permitted situations.

When it comes to managing manure, Bass recommends having a basic, but thorough, common- sense plan that will help guide good decision-making during an emergency. The plan will help the employee, manager or whomever is on the farm when an emergency occurs. It should be unique to the type of management, system and environment found on your dairy.

An emergency action plan for handling a manure spill has six basic steps, as outlined by Bass. They are:

1. Eliminate the source.
2. Contain the spill, if possible.
3. Assess the extent of the spill and note any obvious damages.
4. Contact the appropriate agencies (immediately to 24 hours after the spill occurs).
5. Clean up the spill and make repairs.
6. Prepare and submit a summary report (usually 7 to 14 days later, but varies by state).

There are essentially two types of reporting that need to be done in the event of a manure spill – immediate and follow-up. Check with your local and state authorities to learn the allotted time for each type. “It should be spelled out in your permitted paperwork,” Bass says.

In addition to the emergency plan, Bass suggests a phone tree and resources list be placed in tractors, near where the records are kept, in the cabs of farm vehicles and anywhere else it may be needed. The list should include contact information for top management and personnel, service and equipment suppliers, appropriate neighbors, technical assistance providers, reporting agencies, local government, and water utilities, etc.

With a plan and phone tree in hand, many producers can rest assured, but they shouldn’t get too comfortable.

“I highly recommend the emergency action plan be looked at and updated on an annual basis,” Bass says. A good time to remember to do so is to coincide its review with the annual CAFO permit update process.

During that time, review the plan; re-check the emergency contact list; train/re-train employees, farm family and all new employees; and update and verify that the most recent plan and contact lists are in all necessary locations.

“The most important part of planning is prevention,” he says. Prevention includes self-inspections and record keeping, especially for manure structures, conveyances and equipment.

Clean-up of spilled solids

The response method for a spill is different depending on the type of manure involved.

“When you compare liquids and solids, the pollution potential of solids is less,” says Melony Wilson, animal waste specialist at the University of Georgia. Solids have less movement across a surface and do not infiltrate like liquids can; therefore cleanup can be easier.

Spilled solids typically occur in loading areas, during local transport and long-distance hauling, and in the fields.

Again, prevention can go a long way in avoiding manure spills. Wilson outlines the following preventative methods:

  • Train drivers and land applicators to give them more confidence in what they are doing.
  • Clean up spilled manure from loading areas.
  • Do not overload trucks that are traveling short or long distances. Overloaded trucks are more likely to spill or turn over.
  • Keep pile and truck covers maintained and use them when required.
  • Inspect the equipment before leaving the loading area. One common mistake is leaving the spreader gate open. A walk around the spreader before leaving could prevent this in most cases.
  • Perform regular maintenance and calibration schedules at least once a year.
  • Follow application rates specified in the farm’s nutrient management plan.

When responding to a spill of solids, Wilson emphasizes human safety should always come first and it should be top-of-mind through every step of the clean-up process. Immediately contact the proper authorities and emergency response personnel. Then inspect the site to determine where surface waters are located and find a way to prevent the material from entering those waters. Next, scrape and clean up as much material as possible. Be sure to wash manure off of the roads. If it should get rained on, it will be extremely slick and dangerous, she says. Lastly, replace any erosion control practices and file the necessary reports.

Clean-up of spilled liquids

Shawn Hawkins, animal waste management specialist at the University of Tennessee, stresses prevention in regards to liquid spills.

He says every producer should know and operate within their manure storage parameters, including the maximum number of animals, estimated manure production rates, estimated process wastewater production rates and normal rain (direct rainfall and lot runoff less evaporation). Residuals in liquid impoundments should also be known, as the accumulating solids shorten storage time and may not have been considered in the design.

“In my opinion, every producer should know these figures off the top of their head,” Hawkins says.

Producers should also operate storage facilities with safety factors in mind. Levels for storm event storage and the 1-foot minimum freeboard should always be maintained. Overtopping these limits, Hawkins warns, will damage earthen ponds and turn a small overflow into a catastrophic spill.

Placing depth markers and recording levels weekly can aid in monitoring the performance of your liquid manure storage. If plotted over time, it provides the ability to plan around remaining capacity. If the data does not “balance” over time, it can be an indication there is a leak somewhere.

Hawkins noted lessons could be learned from other industries too. For instance, when welders work there is someone standing by on “fire watch.” He recommended having someone serve as a “leak watch” during manure application. Their sole job would be to verify land application events, observe direct pipe connections and periodically inspect for leaks or punctures.

He also suggested installing a flow meter to record manure flow. Hawkins has used an open bore magnetic flow meter and found it to be durable, accurate and expensive, but well worth the money, he says.

Case study

Erb can illustrate all of these principles in action with a real-life incident he learned about where a tractor and liquid tanker were rounding a curve on the highway. The tractor tire caught the soft shoulder of the road, swerved and pulled the tanker towards the ditch. The operator lost control, and the tanker flipped.

He says the No. 1 thing in this situation, ahead of the environment, is to protect human safety. Once the driver was out of harm’s way and the safety of response personnel in place, actions towards the spill could begin.

Almost immediately a small dam of dirt was created in the ditch to prevent the spill from traveling further. The tanker was pulled back into an upright position, and with rains in the forecast a dam was built upstream in the ditch. A dam of straw was also built downstream to catch and absorb manure and flush water. The fire department flushed the manure off the road and then did a high-pressure, low-volume flush in the ditch to remove the manure from the vegetation. Finally, all manure was removed from the ditch and the area was reseeded.

Lessons to be learned from this example, Erb says, are that quick action and knowing what to do are critical. Every employee needs to know what is in the spill plan and where it is kept, because you do not know who will arrive first in an emergency situation.

During an incident like this, the responsible party (farm owner and employees) should assume the role of maintaining human and bystander safety, notifying proper authorities and initiating containment and clean-up steps. Local responders and natural resource agencies should aid in technical and resource assistance, bystander and traffic control, ensuring site restoration and interagency coordination.

When the news arrives

What if the 5 o’clock news should happen to arrive? Bass says it’s best to have some idea of who is going to be the spokesperson. It can be the farm owner, manager or perhaps the certified planner or agency representative. A simple statement that the contingency plan is being followed will suffice.

“The fact there is a plan for this situation needs to be emphasized to the press,” Bass says.

He also recommends having an environmental policy statement available to give to the press. It would be a simple three-sentence statement that explains what the farm is about, what it produces and how it cares for the environment. This can be provided until a follow-up statement is available. PD

PHOTO: Human safety should always come first when dealing with a manure spill. Having an emergency action plan will help everyone remain calm and thinking clearly. In the situation shown here, Kevin Erb with the University of Wisconsin Extension suggests the bystanders may be too close to the turnover in the event a pull chain would break or come unhooked. Photo courtesy of the Wisconsin DNR.

Karen Lee