Author: John A. Lory, University of Missouri

A manure application setback specifies the minimum distance manure can be applied to a defined feature. For example, USEPA water quality regulations require a setback of at least 100 feet from surface waters such as a lake or stream for permitted animal feeding operations land applying manure. This distance can be reduced to 35 feet when the setback is maintained as a permanently vegetated strip. The objective is to provide a protective strip of land that can serve to filter solids, retain nutrients, or otherwise improve surface water runoff from fields receiving manure.

Prescriptive setbacks are no guarantee that manure and nutrients will not reach surface waters. Some fields may warrant even wider setbacks. Producers should use their past knowledge and experience of their fields to assess the risk of manure runoff. Preventative practices such as maintaining surface residue, rough tillage, cover crops, incorporation, timing, and rates and placement of manures along with setbacks should be considered. A combination of these practices will greatly reduce the risk of runoff on any field. For more information review Capturing Land-Applied Manure in the Rootzone: Sediment and Containment Runoff.

Most manure application setbacks are implemented as part of rules protecting water quality. However, many states have setbacks within their water quality guidelines for non-water features such as occupied dwellings, roads, and public use areas such as parks, churches, and schools.

Setback requirements vary from state to state and for different operation types. All permitted animal feeding operations must follow state permitting guidelines for manure application setbacks. Farmers participating in Natural Resource Conservation Service (NRCS) cost-share programs frequently are required to follow state NRCS setback guidelines. Many states have setback rules affecting specific types and/or sizes of operations. A new Web resource lists manure application setbacks for 34 states; visit http://nmplanner.missouri.edu/setbacks/index.asp.