How does the Manure Spreading Advisory (MSA) work?
The MSA is an advisory tool to help assess if predicted weather
conditions are suitable for manure application. Use this tool in
conjunction with your Oregon Department of Agriculture (ODA) approved Animal Waste Management Plan (AWMP)
and the CAFO Permit.
Click on your farm location on the map below to receive the risk
rating and application guidance for your specific area. Risk is based on
the 72-hour precipitation forecast for a given area. This value best
predicts the potential risk of off-site movement of manure applied to a
If you are still unsure if a manure application is appropriate, please use the geographic CAFO boundaries map to contact your local livestock water quality specialist.
If you are having technical challenges associated with accessing the MSA, please contact ODA.
Manure Spreading Advisory
Legend: What do the risk assessments mean?
Low risk rating
A low risk rating means that an agronomic manure application has a
low chance for a precipitation-caused runoff or leaching event to
Other low risk factors
Include: low to medium soil moisture conditions; adequate
vegetation cover if surface applying; and no ponding or water table
within two feet of the surface.
A high risk rating means that an agronomic manure application has a
high chance for a precipitation-caused runoff or leaching event to
occur and/or impact an adjacent waterbody.
Other high risk factors
Include: Soils are saturated, the water table is within 24-inches
of the surface and/or flowing tiles, is frozen more than one inch down,
has thin vegetation (< 70% density), or high risk areas. High
risk areas are swales, trenches, ditches, ponded areas, or other
conduits that would channel water from the field to adjacent water way.
Do not apply to high risk fields! Wait for them to become more suitable
Please note, even if this map says your risk is low, it cannot
account for every variable or condition present on your field. It is
your responsibility to use your best judgment, adhere to all application
guidelines outlined in your ODA approved AWMP and CAFO Permit
conditions. If unsure, do not apply manure to prevent
unwanted discharges. Manure application practices that cause a discharge
can lead to enforcement action.
The Oregon Department of Agriculture assumes no
responsibility for inappropriate manure application. Proper application
is ultimately the responsibility of the operator.
Thank you to the Whatcom Conservation District for sharing this resource with ODA.
CAFO Geographic Boundaries
Geographic regions for CAFO Program with contact information for livestock water quality specialists. Document
Whatcom Conservation District