In-House Windrow Composting of Poultry Litter

Download work plan

Project Work Plan

This project will demonstrate the environmental effects of treating poultry litter using IWC. The effect of IWC-treated litter on runoff water quality when the litter is land applied will be assessed as well as other benefits of this practice. Data is needed to evaluate parameters such as nutrient load and solubility and E. coli content in runoff water from land upon which IWC-treated poultry litter has been applied. It is anticipated that the IWC procedure should eliminate most E. coli in the litter, thus reducing the potential for bacterial contamination of water resources. If successfully demonstrated, IWC could be used by poultry producers as a standard, cost-effective BMP to reduce the microbial load of poultry litter before it is removed from poultry houses during whole house cleanouts. In addition, implementation of IWC as a BMP between flocks could also eliminate the need for caked litter removal, handling and disposal; thus, reducing the frequency (and potentially the total amount) of litter removed from poultry houses and needing final disposition.

To evaluate the potential benefit to surface water runoff quality, IWC will be performed at a private poultry facility (cooperator site) in either Limestone or Falls County. Bacteria, nutrients, and volatiles in raw and IWC litter will be evaluated prior to land application at USDA-ARS sites in Riesel. A 3 ton/ac application rate will be utilized as recommended by Harmel et al. (2009). This rate is typical for pasture conditions in Central Texas. Additionally, through the use of laboratory and field evaluation of volatile concentrations from litter and from the application sites at Riesel by W-TAMU, the environmental impacts of using IWC poultry litter instead of raw litter will be demonstrated.

At the USDA-ARS watershed sites at Riesel, bacteria levels in runoff will be evaluated to determine the edge-of-field impacts of the BMP. Through a separate project, not funded by this or other CWA §319(h) funds, the water quality impacts of litter and commercial fertilizer application on nutrient runoff from the demonstration sites will be evaluated. Storm and baseflow water quality samples will be collected from USDA-ARS watersheds in Riesel and analyzed for NO3-N, NH4-N, and PO4-P. Bacteria levels (E. coli) in the runoff from the Riesel watersheds will be analyzed by SAML.

Results of the demonstration and practice evaluation will be distributed through publications and grower meetings conducted in year 3 of the project in poultry producing regions of Texas (see map). POSC, SAML, and USDA-ARS, with assistance from TWRI, will develop outreach materials (e.g. refereed journal articles, Extension publications, and other materials as needed) summarizing the results of the demonstration and the analysis of the environmental impacts of IWC poultry litter. These will be submitted to the TSSWCB for review prior to publication. POSC will conduct 6-9 grower meetings throughout the poultry producing areas of the state to present results of the IWC demonstration/evaluation. POSC will work with poultry integrators to deliver 2-3 programs for growers for each integrator (Sanderson Farms, Tyson, Pilgrim's Pride). TWRI will assist POSC by developing press releases, meeting notification materials for distribution prior to the meetings, and post meeting summaries. TWRI, with assistance from POSC and SAML, will also develop, host, and maintain a project website for dissemination of project materials. POSC, with assistance from TSSWCB, TWRI and USDA-ARS, will work with USDA-NRCS to make necessary revisions to various practice standards (i.e., 629 Waste Treatment, 633 Waste Utilization, 317 Composting Facility) to include IWC so that it can be used in TSSWCB Water Quality Management Plans and NRCS conservation plans. Finally, POSC will work with SAML, USDA-ARS, and TWRI to develop a final report summarizing the results of the project.

Project Background

According to the 2008 Texas Water Quality Inventory and 303(d) List, 295 waterbodies in Texas are impaired by bacteria. To address the bacteria impaired waterbodies, Texas is developing and implementing Total Maximum Daily Loads (TMDLs), TMDL Implementation Plans, and Watershed Protection Plans. Many of these waterbodies are located in the poultry producing regions of Texas (see map). Poultry production has expanded significantly in recent years in Falls, Limestone, and surrounding counties. An estimated 550 new poultry houses have been built in this area, producing approximately 60 million broilers annually. If improperly managed, litter (the combination of bedding material and manure) removed from the facilities and land applied represents a threat to water quality through bacterial and nutrient runoff from these fields. By proactively planning for and addressing environmental issues, the impacts from new and existing facilities can be minimized for the long term. To achieve this, additional cost-effective best management practices (BMPs) are needed to reduce the environmental impacts. Furthermore, such BMPs must be demonstrated to area producers in order to achieve their adoption.

One such BMP is in-house windrow composting (IWC) of poultry litter. IWC is a litter management strategy used by commercial poultry producers to reduce pathogenic microorganisms in litter and improve the overall quality of the litter between successive flocks reared on the same litter. While some research has been published about the methodology of performing IWC and the subsequent reductions in bacterial loads in litter, and many managers in the poultry industry currently utilize this technique, no data has been published regarding the effects of IWC on runoff water quality or other environmental impacts when litter that has been treated in this manner is land applied.

In-house windrow composting is a relatively simple technique to implement in a poultry house. After the birds are removed from the houses, the litter is piled into windrows down the length of the house. Natural bacterial metabolism generates heat within the piles. Within 48 hours, the internal temperature of the piles will surpass 131°F, a temperature sufficient to inactivate most pathogenic microorganisms found in litter such as E. coli, Salmonella and various viruses. Litter is typically left in piles for 5-9 days, and then spread out to be reused for the next flock of birds. Turning of the piles may also occur during this time to release moisture, increase aeration and assure that all parts of the litter pile are heated to inactivate pathogens. The IWC process has been referred to as a "pasteurization" procedure rather than composting, but the term "composting" is widely used in the literature and poultry industry.

If demonstration/evaluation of this practice shows it to be effective at reducing the loadings of nutrients, bacteria, and volatiles, this practice could then be added to the list of approved practices for Water Quality Management Plans for poultry operations. State law requires all poultry operations in Texas to operate in accordance with a TSSWCB certified WQMP. Additionally, if effective, the practice could be added by NRCS to the Field Office Technical Guide. This would not only benefit Texas, but poultry operations nationwide.


  • To reduce the environmental impacts of land application of poultry litter by using in-house windrow composting (IWC) of poultry litter to reduce the levels of bacteria, nutrients and volatiles in litter and thus result in a reduction of the edge of field levels of these constituents.
  • To demonstrate and evaluate the use of IWC of poultry litter to reduce bacteria and nutrient levels in surface water runoff, thereby providing an additional BMP for addressing bacteria and nutrient impairments in Texas.
  • To transfer findings of this demonstration to poultry producers throughout the state by working with all major poultry integrators in Texas to distribute a series of outreach materials and host producer meetings, in order to increase the awareness of poultry producers and integrators of the environmental issues in the state and the ability of IWC to address those issues


  • Demonstration of IWC of Poultry Litter
  • Analysis of Environmental Effects of IWC
  • Technology Transfer

Measures of Success

  • Reduction in levels of bacteria, nutrients, and volatiles observed between IWC litter and raw litter
  • Reduction in bacteria, nutrients, and volatiles loading from sites where IWC litter is applied vs. where raw litter is applied
  • Number of educational programs conducted
  • Number of people attending educational programs
Back to Top