Tuesday, October 1, 2019

Plan now to manage manure and water this winter

Kerri Love
WSDA Dairy Nutrient Management Program

Cement blocks and fences hold manure
 and cows back from wet, muddy areas. 
As the days grow short and bunkers are loaded with the summer’s crops, it is also time to ensure manure lagoons are empty and ready for winter rains and storage.

Don’t lose valuable nutrients to rain

Late season nutrient applications have special risks. Fields may be compacted from harvest and application equipment. The dry summer may have reduced forage crop density. Applying nutrients where they may run off or pool in low spots of your field after our first big rainfall wastes your time and money, and is a risk to water quality.

Apply nutrients in the right place and at the right rate to ensure they enter the soil where your crops need them most.
Following best practices, a tractor
 incorporates manure after an
Use expanded buffers, avoid bare soils or slopes, and apply at a rate appropriate for the field and soil conditions.
Do not pasture animals or apply nutrients to flood-prone areas of fields.
Incorporate solids into bare fields, especially after corn harvest where soils can be highly compacted from silage trucks.

To evaluate weather and run-off risk, check the three-day forecast for rainfall.
A great tool in Western Washington is the Manure Spreading Advisory tool. Click on the map on a location near you and see a 72-hour weather forecast with an associated risk rating for applying nutrients.
Pro tip – you can print the weather forecast or save a screen shot, and use it as part of your application record keeping.

Pastures and heavy-use areas (HUAs)

Move cows off pastures before they get wet.
Remove animals before fields are saturated, then drag a harrow behind your tractor to distribute manure.

Reseed animal lanes or HUA’s with winter wheat, while there is still light and warmth to get seeds going.


You should always have at least 12-15 inches of freeboard from the top of your lagoon or 12 inches from the top of an upright tank, to allow for a 24-hour (25-year) rain storm.
If you have more nutrients than storage this fall, work with neighbors, custom applicators, and your local conservation district to locate appropriate application locations or storage structures.

Do not direct silage leachate to the ground or water.
Feed-bunker leachate should be collected and transferred to storage.
Vegetated treatment areas (VTA) must be designed to treat the volume of runoff expected, and must be healthy enough to trap and absorb the nutrients carried in the runoff.
If not designed well, concentrated runoff from the feed area can “burn” the grass and destroy these treatment areas rendering them ineffective and requiring diversion to storage.
Conservation district planners can provide guidance on whether your VTA is adequate for preventing a water quality issue.

Small fixes now go a long way

Check your gutters and downspouts to ensure they are clean and connected.
Did you know that an inch of rain on a 10,000 square-foot roof amounts to 6,000 gallons? If clean water isn’t properly diverted, then it’s being collected and is transferred to storage. Collecting clean water will fill up your lagoon and may cause you to lose sleep come March!
Know where water flows.
Park manure handling equipment (scrapers, manure spreaders tankers and hoses), away from surface water and storm drains.
Avoid manure track-out, and keep manure off surfaces that may run to ditches or storm drains.

Be prepared

To prevent a manure spill:

Maintain a 12-inch freeboard in lagoons, plus an extra 4-6 inches to accommodate rain from a 25-year, 24-hour storm.
Inspect storage structures regularly for signs of leaks or problems.
Inspect valves, pumps, hoses, and other manure conveyance equipment before and during use.
Conduct routine maintenance and repair to prevent failure.

Have a plan!

Post emergency numbers where they can be easily seen and found in a hurry - on the wall in your office, in the milk house, and/or in the breakroom. Post the farm address including the numbers below, so callers know exactly where to direct responders.

Numbers to include:
Emergency first responders - 911
Farm managers/operators cell and home numbers
Ecology – Spills to water 1-800-258-5990
WSDA – To report a spill 360-746-1249
CAFO permitted facilities-- 1-800-407-6600; call within 24 hours of the spill

If you have questions about winter manure management, please contact your local conservation district or Kyrre Flege with WSDA’s Dairy Nutrient Management Program at 360-746-1249.