Revised:  09/14/2012

Ask the Expert -- Farm and Pasture Management













Farm and Pasture Management

Manure Management



Can horse manure pollute an aquifer?

A company started taking horse feces to their dump down the road from my house. The smell is what got our attention. We are very worried about our water aquifer which runs just 32 feet below the dumping site. We live in Ocala FL, which has lots of horses and tons, and tons of horse feces. We are worried it is going to get into our aquifer. Would it be a health concern if it did?


Below are some general guidelines that are used for placement of manure storages. It wasn’t clear from your note whether your storage is 32 feet below (underground) the storage or whether 32 feet of land separates your aquifer from the manure. If the aquifer is 32 feet under the dump site, I would guess there is less risk than if 32 feet separated the dump site from your property line or water source. Of course distance to water table and bedrock are probably much different in Florida than in New Jersey. I would suggest contacting your State Department of Agriculture division that deals with animal waste storages. They could give you better information about setbacks, property line distances, etc.


In general horse manure will have fewer odors than other types of manure (hog, dairy, poultry). If stored relatively dry, odors should be negligible. However, if wet or if another wet biological material is added, then odors will be much worse. Regarding health risks, although horses have been shown to carry fewer pathogens such as toxic E. coli, Salmonella (shedding of Salmonella is negligible), or protozoa such as Cryptosporidium, I can understand your concern and would take whatever precaution is necessary. I suggest getting your water tested to determine if any of these pathogens are present. Your county public health department should be able to do this for a fee. They can test for various bacterial or protozoal pathogens and determine if there is a risk or not.


My suggestion is to take precautions to prevent contact between horses and water (streams, lakes, etc.). I realize that this is not always possible, but if you can, design or modify trails in such a way as to prevent defecation in streams, and minimize the risk of contamination around streams by the use of vegetation, buffers, etc.




Answer provided by Mike Westendorf, Ph.D., PAS, Department of Animal Science, Extension Livestock Specialist.


My neighbor's horse manure drains onto our property; what are the regulations to stop this?

I have a few questions regarding my neighbor’s horse. In our township, one horse on one acre of land is permitted. The ordinance does not stipulate how close horse facilities can be to the property line and an existing neighbor. In our case, the horse pen is right up against our fence. The horse farm owners never clean up the horse manure, and when it rains the manure comes into our yard. The distance between the horse pen and our drinking well is approximately 80 feet. Last week, our water tested positive for E. coli and coliform. To make matters worse, the horse’s pen is filled with dirt, so the horse is allowed to graze freely in the existing back yard that is not fenced. The horse is gentle, however it is a large animal and I have small children. I am fearful for the health and well being of my family. Can anyone just throw a horse in the back yard because they have an acre of land?


Have you tried approaching your neighbor to discuss your concerns? They may not be aware that the poor care for their horse is a problem. Get someone knowledgeable about horse care (local extension agents, 4-H leaders, etc.) to assess the situation with you.

You need to check with local officials regarding regulations on keeping livestock in residential areas. Townships that do not ban all livestock vary in their regulations. The table below gives a general guideline for minimum recommended distances from manure accumulation:

Minimum distances between manure accumulation/storage/composting areas and other activities

Sensitive Area Minimum Separation (Feet)
Distance (feet) from property line 50-100
Residence or place of business 200-500
Private well or other potable water source 100-200
Wetlands or surface (streams, pond, lakes) 100-200
Subsurface drainage pipe 25
Water table (seasonal high) 2-5
Bedrock 2-5
(Adapted from On-Farm Composting Handbook, NRAES 54, 1992)

Please remember that these are suggestions. You also might want to go to your township and let them know of your concerns, especially if your neighbors are resistant to changing their practices.

E. coli is ubiquitous in the environment, so it is hard to tell if your neighbors’ horse was responsible. In general, horses do not excrete the most toxic forms of E. coli, nevertheless any coliform is of concern and you should make your test results known. Your neighbors probably share the same acquifer as your well so the contamination should be of concern to them too. Some kind of berm or buffer to channel all waste away from your property will need to be installed. In addition, any manure that is stored should be at least 100 feet from property lines and/or any water sources.

The free roaming horse is also a major problem in a densely populated area. Not only is it a potential danger to you and your children but also to the horse, which could wander onto a road or other areas where it might get stuck by a motor vehicle or injured. It is very likely that unfenced livestock will violate township ordinances. If nothing changes, you may want to consider fencing in your own backyard for your children’s safety.


Answer provided by Mike Westendorf, Ph.D., PAS, Department of Animal Science, Extension Livestock Specialist, Sarah Ralston, VMD, PhD, DACVN, Department of Animal Sciences, and Laura Gladney, Program Associate, Rutgers NJAES Cooperative Extension.



Does horse manure on trails pollute water?

We have horseback riding trails in our park, which we share with hikers. Our policy has been to let equestrians leave their horses' manure on the trail rather than cleaning it up. We instituted this policy because it is safer than having riders get off their horse to try and remove the manure while there are people walking by.


Eventually park staff removes the manure, or it dries and is left to decompose. But we are concerned that if the manure is left on the trail, it may affect water quality. If there is a heavy rain, will the manure leach into the soil and get into the ground water? Or are the chances of the manure affecting water quality low, given the small quantities we’re dealing with?



Depending on its location and management, horse manure could be a concern to water quality; however, I consider it to be a small if not insignificant concern given your situation.


It is unlikely that horse manure from horses on trail rides poses a great risk to ground water. Nitrogen present in urine will most likely be volatilized to ammonia gas very quickly and lost into the atmosphere. Nutrients in feces will be associated mostly with organic matter. Nitrogen will be converted (mineralized) to ammonium or nitrate slowly over several years. Nitrate could leach to the ground but it would be a slow process, and given the number of horses, would probably be an insignificant source. The leaching risk from other nutrients (phosphorous, potassium) would be much less. Your main risk to water quality will come from runoff, not leaching, particularly if your trails follow streams and/or cross streams regularly and if runoff from steep hillsides leads to water. Then there will be a greater concern.


My suggestion is to take precautions to prevent contact between horses and water (streams, lakes, etc.). I realize that this is not always possible, but if you can, design or modify trails in such a way as to prevent defecation in streams, and minimize the risk of contamination around streams by the use of vegetation, buffers, etc.


I would agree with your assessment that the risk is low, especially given the small quantities of horse manure that you are dealing with. Wildlife (deer, elk, etc.) and livestock (beef cows, sheep) may be more of a water quality risk on public lands than trail-riding horses.

I have included below a brief overview of pathogens in horse manure and risks to humans.


Pathogenic Microorganisms in Horse Manure



According to the National Animal Health Service, Salmonella is believed to be present in horses at very, very insignificant levels. According to this report, Salmonella was found on 0.08% of the operations sampled and in 0.02% of the horses in the northern region of the United States, including New York and New Jersey. What this translates to is 1 in 125 farms had at least one animal shedding salmonella but only 1 in 500 horses shedding salmonella. (Please see Salmonella in the US Horse Population, 2001, USDA-Animal and Plant Health Inspection Service,


E. coli

While E. coli from a number of species, including humans, can cause intestinal disease under certain conditions, no incidence of human disease from E. coli of equine origin has been documented. The bacterial pathogen of greatest concern is E. coli 0157:H7. Research conducted at the University of California has indicated that insignificant amounts of E. coli 0157:H7 were found in adult horse intestines. For more information, you can contact Dr. Rob Atwill at the University of California at Davis, Veterinary School, or Dr. Patrick McDonough, Cornell University Veterinary Diagnostic Laboratory.


Cryptosporidium parvum and Giardia

Cryptosporidium is present only at very low levels in horses. One study found 0.33% of horses were carrying Cryptosporidium parvum and in the same study they found 0.66% of horses carrying Giardia. This means that 1 horse out of 300 was carrying Cryptosporidium and 2 horses out of 300 were carrying Giardia. Work done by other researchers has also found low levels of Cryptosporidium and Giardia. (Please see the following publications: Journal of Veterinary Diagnostic Investigations, “The prevalence of shedding of Cryptosporidium and Giardia spp. Based on a single fecal sample collection from each of 91 horses used for backcountry recreation." Volume 9, pages 56-60, 1997.Proceedings of the 15th Equine Nutritional Physiology Symposium, “The prevalence of Cryptosporidium/Giardia in the trail horse population utilizing public lands.” Proceedings, pages 223-237, 1997.)


Another paper looks at the use of buffer strips to filter Cryptosporidium and shows that when slopes were less then 20% with good ground cover (they used tall fescue grass), and when the length of the buffer strip was 3 meters in length or greater, this was sufficient to remove 99.9% of Cryptosporidium parvum oocysts. (See the article at the Journal of Applied and Environmental Microbiology, “Transport of Cryptosporidium parvum oocysts through vegetated buffer strips and estimated filtration efficiency,” Journal number 68, issue 11, pages 5517-5527, 2002.)



I know of no linkage between campylobacter in the horse gut and human health. The Merck Veterinary Manual, Eighth Edition, 1998, makes no reference to Campylobacter disease in horses.



Not a bacteria, Leptospira is a spirochete that can infect horses, occasionally causing abortion or uveitis (an eye infection). It is not transferred in the feces but in other bodily fluids, e.g. urine. No known incident of human disease as a result of equine infection. Proper control of water runoff and maintenance of pastures as well as appropriate animal health treatment will eliminate any risks. For more information contact Dr. Rob Atwill at the University of California at Davis, Veterinary School, or Dr. Patrick McDonough, Cornell University Veterinary Diagnostic Laboratory for more information.


While horse manure may not be attractive, it should not be harmful to human health nor pose a significant health risk to people when they come across it on trails.


Answer provided by Mike Westendorf, Ph.D., PAS, Department of Animal Science, Extension Livestock Specialist.



What is the best way to dispose of manure in a suburban area?


I am the manager at a large farm that is in the middle of a residential area. I have 70 horses on the grounds and my manure is a problem. I have to haul it out in 30-cubic-yard dumpsters 3 times a week and it is becoming very costly! Do you have any suggestions on how or where I should dispose of some, if not all, of the manure?



Unfortunately, there are no easy solutions when you have so many horses in an urban/suburban area. The easiest solution with so many horses would be to bed with straw. If you did this I am sure you could dispose of your manure with Pennsylvania mushroom growers at no or low cost.


If this is not an option, then composting may be if you have enough space and an appropriate site. A proper compost site should be level, well drained, and at least 100 feet from any bodies of water. Storm water runoff should be controlled and there should be an abundance of vegetative cover or buffers surrounding the site to prevent any contamination of surrounding water bodies, wetlands and the environment. It should be built on an impervious base. This can be earthen but more likely will have to be concrete depending on the soil type, drainage, etc. You can get advice from the Natural Resources Conservation Service (NRCS) about composting sites. Unfortunately, you will still have to dispose of your compost off-site. This may necessitate other regulatory approval. Farmers can produce their own manure compost for spreading on their own farms, but as soon as it is disposed of offsite (above a certain amount) it will be regulated and may require a permit. There is discussion on the state level to ease the regulations on manure composters disposing of their product off-site.


Depending on what you use for bedding, the manure may have more fertilizer value. If you bed heavily with wood products (shavings, chips, etc.) the product will have value as a soil amendment providing organic matter to the soil, but will not be as valuable as horse manure without bedding. Unfortunately the wood products can make the nutrients in the horse manure less available in the soil. Straw-bedded manure would be somewhat more valuable but would also be available for disposal on mushroom farms.


The upshot is that if you bed with wood products and if you don't have much space for a composting or storage facility, you may not have a lot of options other than what you are already doing. I would suggest you contact the local NRCS; they will visit your farm and may have some helpful suggestions.


Answer provided by Mike Westendorf, Ph.D., PAS, Department of Animal Science, Extension Livestock Specialist.



What is the status of New Jersey's Equine Waste Management regulations?



Does New Jersey have an Equine Waste Management law up for a vote in the Committee in Trenton? Would this law require horse farms to report a Manure Management Plan to the state?



**Updated Answer - November 2011**


This rule was approved in March 2009.


New Jersey Legislature required the New Jersey Department of Agriculture to develop a comprehensive animal waste management program in order to provide for proper disposal of animal waste, establish standards for storage, handling, and disposal, and establish penalties for non-compliance. The draft underwent an informal industry review in 2004, and three public meetings were held in 2005 for input from the public. An Animal Waste Advisory Committee, made up of farmers, Rutgers University personnel, New Jersey Farm Bureau, and state government, reviewed the rule before it entered a 60-day public comment period in 2008. It was approved by the State Board of Agriculture on February 9, 2009.


There are two parts to the rule: the first is the five General Requirements that apply to every livestock farm in New Jersey.

Requirement 1 states that animals in confined areas shall not have uncontrolled access to waters of the state. A confined area is one that does not have vegetative cover, such as a dry lot, exercise yard, “paddocks” and stables. A true pasture with 70% or more vegetative cover is not considered a confined area.
Requirement 2 states that manure storage areas must be at least 100 feet away from state waters.
Requirement 3 states that manure must be spread in accordance with the principles of the NJDA BMP Manual and the USDA-NRCS Field Office Technical Guide. The BMP manual may be found here: and the FOTG may be found here:
Requirement 4 states that no livestock that have died from a reportable contagious disease listed in N.J.A.C. 2:2-1.1 or as a result of an act of bio-terrorism shall be disposed of, composted or made part of any land application without first contacting the State Veterinarian.
Requirement 5 states that any person entering a farm to conduct official business related to these rules shall follow bio-security protocol.


The second part of the rule is the creation of an Animal Waste Management Plan (AWMP) by any farm which is required to do so. Farms are divided into four categories based on the number of Animal Units (1 AU = 1,000 pounds of animal weight, or 1 average sized horse) and Animal Density (number of AUs per acre). Farms receiving manure may also need to file a plan. Every farm in every category is responsible for following the five General Requirements as well as:

1 to 7 AU: Encouraged but not required to develop and implement a self-certified AWMP.
7 to 399 AU: less than or equal to 1 AU/acre: Must develop a self-certified AWMP and submit a Declaration Page to their local Rutgers Cooperative Extension office.
7 to 399 AU: greater than 1 AU/acre: Must develop a high-density AWMP and submit the plan to their local Soil Conservation District for approval.
300 or more AU: Must develop a Comprehensive Nutrient Management Plan (CNMP) in consultation with Natural Resource Conservation Service (NRCS), a Technical Service Provider, or other appropriate agent, and submit the CNMP to the local Soil Conservation District for review and approval.
• Farms receiving less than 142 tons of manure/year: Encouraged but not required to develop and implement a self-certified AWMP.
• Farms receiving 142 tons or more of manure/year: Must develop a self-certified AWMP and submit a Declaration Page to their local Rutgers Cooperative Extension office.


All farms were required to comply with the five General Requirements by March 2010, complete their AWMPs (if required) by September 2010, and complete all BMPs in their AWMP by March 2012. There are penalties for noncompliance; however, a farm owner will not be penalized for submitting an AWMP after the deadline. Any farm owner who would like assistance in preparing an AWMP can contact their local Rutgers Cooperative Extension, NRCS, or Soil Conservation District office or the New Jersey Department of Agriculture. A paper or online template to create an AWMP is available for download at



Original Answer

These regulations are still being discussed by a team of farmers, Rutgers University personnel, New Jersey Farm Bureau, and state government. They will not be voted upon, but rather will be approved by the State Department of Agriculture and the New Jersey State Board of Agriculture. It should encourage New Jersey farmers that the majority of participants at a recent meeting were farmers (current and former) from the dairy, equine, beef, and other industries.


The rule will have a tiered approach with only larger farms (perhaps 200-300 animal units) having to complete a fully certified nutrient management plan. Farms having more than 8-10 animal units all the way up to the higher threshold will complete a self-certified plan. The smallest farms (less than 8-10 animal units) will not be required (but encouraged) to complete any plan at all.


Remaining issues relate to the determination of these threshold numbers, what constitutes an animal unit, and education and enforcement provisions.


Probably the most difficult issue remaining is how to regulate manure waste imported to or exported from the farm. For example, it is still unknown who would be responsible to have an approved management plan when waste leaves the farm: the importer or the exporter.


Answer provided by Mike Westendorf, Ph.D., PAS, Department of Animal Science, Extension Livestock Specialist.


What are the laws for spreading manure near a property line?



I have a neighbor who spreads her manure right along our fence line, which separates our pastures. Is this practice of manure spreading so close to a neighbor allowable in New Jersey? I obviously have concerns for the safety of my horses - about the water runoff and parasite control. Can you give me any advice?



New Jersey actually does not have any laws that address the practice of spreading near property lines. The law is that manure storage (the permanent pile) must be at least 100 feet from surface waters. It is recommended that the storage be at least 50 feet from property lines, but again that is for storage and not spreading. However, laws do come into play when manure runoff contaminates surface water. If contaminated runoff is coming on to a farm, then farm owners should talk to neighbors and explain why the runoff is a concern. There are a few practices manure spreaders could adopt to reduce this runoff: 1) leave a 15 foot buffer between the property line and the manure spread, or 2) constructa berm on the side where the water runs off. If steps are not taken to reduce the runoff, it could be a municipal issue. If a farm has more than 7 Animal Units (1AU = 1000 lbs of animal weight), it is required to have an Animal Waste Management Plan and adhere to the five general requirements of the law. Click on “Agricultural Waste Management Practices” for more information. On this webpage, the “What is Required” pdf provides basic information.



How can I kill Strongyles that are in my pasture?



How can you treat land that has housed a horse with a reoccurring positive test for Strongyles? The horse is now relocated but I now know this horse still had Strongyles and I want to treat the areas where he was located. Does putting down lime kill any parasites that may have gotten in my soil?



The best way to kill parasites on pasture is with dry heat. Since parasites don’t actually “live” in the soil, proper spreading of manure in fields combined with cooperating weather is best. Spread/drag empty fields when temperatures are above 80 degrees and sunny, with no rain in the forecast. The Strongyle larvae cannot survive high heat without any moisture. If fields are dragged, manure piles will be spread and dry quickly, and will not hold moisture for the parasites to live. Parasites will not survive on grass or soil alone unless another horse comes along that is shedding parasites and starts the cycle again.


As for the horse with the Strongyles, it sounds like the parasites are resistant to anthelmenthic. It is best to work with your veterinarian to develop a deworming program based on routine fecal egg counts and dewormer rotation.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



The material provided on this site is for educational purposes only and is not intended to diagnose, prevent, or treat any illness. Any recommendations are not intended to replace the advice of your veterinarian. Any products mentioned are not intended to diagnose, treat, cure, or prevent disease. Mention or display of a trademark, proprietary product, or firm in text or figures does not constitute an endorsement by the Equine Science Center or Rutgers University and does not imply approval to the exclusion of other suitable products or firms.







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