It is important that agricultural zoning ordinances be carefully devised and based on fact and not emotion for the protection of farmers and their nonfarm neighbors (Figure 1). Municipal ordinances to remove farm animals from city limits played a central part in defining city planning’s role in urban ecosystems, economies, and public health throughout the 1900s. Broadly speaking, cities enacted ordinances restricting animal agriculture in four waves (Brinkley and Vitiello, 2014).
The first prevented cattle and swine from running at large through the streets. Cities augmented these acts with restrictions on driving/herding animals, which subsequently determined the locations of stockyards and slaughterhouses. In the mid-nineteenth century, laws followed pertaining to the keeping of swine within city limits. With the swill milk scandals of the 1860s, cities created laws targeting dairies which, in part, led to passage of the Pure Food and Drug Act in 1906. Finally, zoning ordinances in the 1920s banned most farm animals from cities altogether.
Poultry were the last farm animals to be banned in the early twentieth century and are often the first to be reintroduced in the twenty-first century. One thing that the COVID-19 pandemic taught us is that city dwellers often turn to urban agriculture in times and places of scarcity. As urban agriculture gains in popularity in the early twenty-first century, urban planners are seeking ways to reweave certain elements of animal agriculture into cities. Perhaps planners’ increasing focus on biodiversity and integrated land uses will create greater space in cities for animal agriculture (Brinkley and Vitiello, 2014).
However, those opposed to commercial poultry farming are not always of the same mindset, and in April 2021 convinced a Maryland circuit court judge to reverse the Maryland Department of the Environment’s (MDE) 2020 Animal Feeding Operation (AFO) Discharge Permit for not considering ammonia emission discharges into the air from poultry farms as a pollutant into the water, since the ammonia discharges could fall into waters covered by the Clean Water Act (CWA) (Goeringer, 2021). Why is this important? Because the decision could have real-world implications far beyond the agricultural sector in Maryland.
We now have an activity (discharges from a poultry house) currently exempt under the Clean Air Act (CAA) at odds with a circuit court ruling that would regulate the discharges under water pollution statutes. Courts often try to avoid irrational results or putting statutes in conflict with each other when interpreting statutory provisions (Goeringer, 2021). However, the Maryland ruling appears to create a direct conflict between the CAA and the CWA. The decision is being appealed and we will await the final outcome.
In the poultry industry today, one of the most important aspects of a zoning ordinance for poultry farms relates to the setback distance required for the location of poultry production houses. Excessive setback distances from property lines and non-owned dwellings severely restrict or totally prohibit the construction of poultry houses because of the large tracts of land necessary for compliance. (In this case, “non-owned” means not owned by the individual wishing to build the poultry houses. This could include private residences, churches, schools, etc.). As a result, opponents of poultry production will often argue for the most restrictive setback distances possible to hinder or shut down poultry production in an area. These individuals will often use unfounded or false accusations concerning air quality, health, odor, environmental, and quality-of-life issues to advance their position (Cunningham, 2006).
Environmental Concerns
Individuals opposed to poultry farming often use the argument that environmental pollution is a major problem associated with modern-day poultry farming. However, a properly managed poultry farm is not a threat to the environment and does not cause pollution or environmental concerns, for either its neighbors or the local community at large. On the contrary, poultry farms produce manure nutrients as a by-product of raising birds that can provide a valuable natural fertilizer and organic soil amendment for pastures, hayfields, and row crop land.
Depending on soil test results, this natural fertilizer can be land applied at the appropriate agronomic rate instead of using more expensive commercial fertilizer. Care should be taken, however, because the nutrients in poultry litter have the potential, just as in any fertilizer source, for runoff and water pollution problems if not handled properly.
Odors
Many individuals unfamiliar with modern poultry farming practices often think that it is impossible to live near a poultry farm because of the smell and odors. This simply is not the case. The huge majority of poultry farms are family-owned operations and, for the most part, the families that own and operate the poultry houses live next to the houses.
Because of ongoing advancements in ventilation and drinking systems and training programs that help growers understand the importance of maintaining dry litter, there is minimal odor emitted from properly managed and operated poultry houses today. Wet litter may occur on occasion and can be a source of odor. However, wet litter can be corrected with proper management and is often a short-lived situation.
Air Quality
Air emissions and odor concerns (especially ammonia) are important issues today for the poultry industry from both environmental and nuisance points of view. It is important to understand ammonia dissipation from poultry houses for the good of family poultry farms, poultry companies, and local governments that may be addressing nuisance complaints concerning this issue.
In the poultry industry today, poultry houses are built with tunnel ventilation systems, which places cool cells at one end of the house and tunnel exhaust fans at the other, concentrating the discharged air all at one end. As a result, some people have the false perception that all the fans and discharge air at one end causes issues for neighbors living near the poultry houses. However, exhausted air from tunnel fans only results in measurable air movement within about 100 feet from the poultry house (Cunningham and Ritz, 2015).
Most states with a commercial poultry industry currently have setback distances in place for siting poultry houses that help maintain the success of family-owned poultry farms, help ensure a stable and consistent tax base for communities where the commercial poultry industry operates and provide protection for all citizens (farmers and non-farmers) in the area. For example, current Mississippi Department of Environmental Quality (MDEQ) setback distances for dry litter poultry operations are 150 feet from the nearest adjoining property line and 600 feet from the nearest non-owned occupied dwelling or commercial establishment. MDEQ also has setbacks in place for land application of litter material. Land application of dry poultry litter waste must be at least 25 feet from the nearest adjoining property line and at least 150 feet from the nearest non-owned occupied dwelling. Setback distances from several other commercial poultry producing states are listed in Table 1.
Table 1. Setback distances for several states with large commercial poultry industries.
| State | From property line | From non-owned residence | Other |
|---|---|---|---|
| Alabama | 165 feet | 330 feet | |
| Arkansas | None | None | |
| Georgia (county level) | 100 to 400 feet | 300 to 500 | |
| Mississippi | 150 feet | 600 feet | |
| North Carolina | 50 feet | 500 feet; 200 feet with permission of adjoining landowner | 1,200 feet from a church or school |
| South Carolina | 200 feet for less than 500,000 lbs; 400 feet for 500,000 to 1 million lbs; 1,750 feet for more than 1 million lbs; Can be reduced with consent | 1,000 feet; Can be reduced with consent | |
| Tennessee | 100 feet | 500 feet | 1,500 feet from a church, school, park, or city limits |
Some individuals opposed to poultry farming may promote excessively restrictive ordinances and setback distances based on negative perceptions of poultry farming. However, these negative perceptions are often related to a lack of understanding or accurate knowledge of modern poultry farming practices. As mentioned earlier, one such perception is that ammonia coming from chicken houses makes it difficult to live anywhere near a chicken house or poultry farm because of odor issues. However, research data from Fairchild et al. (2009) disputes this perception:
- Ammonia concentrations were 1 ppm or less for approximately 85, 90, and 95 percent of the measurements made at 200, 300, and 500 ft downstream from poultry houses, respectively.
- Ammonia concentrations were lower as distance from the poultry houses increased, with ammonia levels at 100, 200, 300, and 500 ft being less than 1 ppm in approximately 60, 75, 85, and 90 percent of the observations, respectively.
- Ammonia concentrations extending to 100 ft from the houses were influenced by the tunnel ventilation fans.
At no time did measured ammonia levels meet or exceed established Occupational Safety and Health Administration-U.S. Environmental Protection Agency ammonia odor-detection threshold values of between 5 and 50 ppm.
Acreage Requirements
The greater the setback distance adopted the more acreage that is required to site poultry houses. Recently, Cunningham and Ritz (2015) calculated setback distances and acreage requirements to site a four-house poultry farm. Their calculations indicate that a 200 feet setback from property lines requires a minimum of 14 acres to site four poultry houses if the land is a perfect rectangle. Increasing the setback to 400 feet increases the requirement to a minimum of 30 acres. A 1,000 feet setback would require at least 130 acres. Since few plots of land are a perfect square or rectangle and most are irregular in shape, property boundaries and topography often result in additional acreage.
Cunningham and Ritz (2015) reported that, in reality, a 200 feet setback may require at least 30 to 40 acres to meet site requirements for an average four-house poultry operation. A 1,000 feet setback could realistically require several hundred acres to site four poultry houses on many tracts of land because of irregular property lines and topography of the landscape (Figure 2). Therefore, a 1,000 feet setback requirement would essentially eliminate large numbers of small family farms across the country from participating in poultry farming because many small farmers may own 40 acres or less, and not the hundreds of acres of land that a 1,000 feet setback may require.
Vegetative Buffers
In some areas vegetative buffers can be used to reduce the setback distance that a poultry farm must have (Scott, Jr., 2017). Vegetative buffers consist of multiple-row plantings of suitable trees, grasses and shrubs planted around poultry houses and related structures such as manure sheds and composting structures. These buffers are usually placed between the farm and neighbors or roadways and, in addition to reducing the visibility of the farm, they are helpful in capturing dust and feathers expelled by the exhaust fans. Additionally, they can also help to capture nutrients and prevent them from causing problems in local waterways.
Summary
Local ordinances related to agricultural zoning can have a huge impact on rural economies and poultry industry operations in an area. Zoning ordinances should be based on fact and not emotion for the protection of farmers and their nonfarming neighbors in rural communities. It is important to seek out common ground that will allow farm families and rural economies to thrive in today’s political and environmental climate
References
Brinkley, C., and D. Vitiello. 2014. From farm to nuisance: Animal agriculture and the rise of planning regulation. J. Plan. Hist. 13(2):113-135.
Cunningham, D. L., and C. Ritz. 2015. Facts for County Planners: Set-Backs for Poultry Houses. University of Georgia Extension Circular 931. October.
Cunningham, D. L., and C. Ritz. 2015. Facts for County Planners: Zoning Issues and Poultry Production. University of Georgia Extension Circular 932. October.
Fairchild, B. D., M. Czarick, L. A. Harper, J. W. Worley, C. W. Ritz, B. D. Hale, and L. P. Naeher. 2009. Ammonia concentrations downstream of broiler operations. J. Appl. Poult. Res. 18:630-639.
Goeringer, P. 2021. Maryland circuit court judge reverses final Maryland AFO permit. Commercial poultry news. University of Maryland Extension Commercial Poultry Newsletter. April.
Scott, J.D., Jr. 2017. VEB TOOL-KIT A Guide to Vegetative Environmental Buffers for Tunnel-Ventilated Poultry Houses. http://www.dpichicken.org/resources/docs/DPI-VEB-toolkit-2017-edition.pdf.
Tabler, T., J. R. Moyle, F. D. Clark, Y. Liang, and J. Wells. 2018. Setback distances for poultry houses. Mississippi State University Extension Service Publ. No. 3209. March.