How manure storage can keep nutrients out of surface water

Right-sizing your manure storage.

Manure storage in ground.
Manure storage in-ground. Photo by Sarah Fronczak

Farmers care for the environment every day. They are stewards of the land working to apply the right nutrients at the right place, time and rate. Manure storage allows farmers to better achieve the 4R's of nutrient management

Why do you need a storage facility? 

Manure storage allows more flexibility in timing for manure management by allowing farmers to store manure during times when weather and field conditions aren't good for applying manure. It also allows farmers to apply manure at the proper time for crop growth. Farmers that don't have adequate storage, may need to apply manure during a time that poses a higher risk for loss to the environment such as during rain and snow melt. Storing manure allows farmers to improve their management of when and where the manure is applied. 

Principles of manure storage

  1. Keep the clean water clean. Divert roof and surface runoff from manure storages and animal lots. Gutters, downspouts and underground pipes are often the best way to accomplish this. 
  2. Treat the dirty water. Any rainfall landing on manure storages and animal lots should drain to a treatment area like a vegetated treatment strip. 
  3. Store the manure out of a flood hazard area. Flood waters that can reach manure storages will carry away manure downstream and cause water quality problems. 
  4. Avoid steep slopes. Steep slopes are harder to manage and increase the potential for offsite runoff. 
  5. Follow a nutrient management plan. These plans take into account the nutrient contents of the manure, the nutrients in the soil and the needs of the crops. 
  6. Follow a nutrient management plan. These plans take into account, the nutrient contents of the manure, the nutrients in the soil and the needs of the crops. 

How big should your manure storage facility be? 

You should take into account, several factors that contribute to the volume need in a manure storage facility. Factors to consider include: type of livestock, type of operation, number of animals, climate, storage period and other water inputs. 

Let's consider your manure storage period. You need to account for field conditions that won't allow for safe application of manure like frozen and saturated land. Michigan doesn't prohibit the application of manure to snow covered ground. However, GAAMP's suggest that the practice should be avoided and at all times, provisions need to be made to control runoff and erosion. A storage period should be selected so that manure isn't land applied during unsuitable soil conditions. 

Another important consideration is that manure should be spread on a growing crop/cover crop or as near to the planting time as possible to allow for crop uptake. As a recent study of beneficial management practices in the Great Lakes Region suggests, a cover crop and rye double crop are effective BMP's in reducing phosphorus loss. Phosphorus is a key cause of harmful algal blooms in lakes and rivers. 

What's the next step? 

If you're interested in better manure storage, please contact myself or Erica Rogers, the Environmental Management Educators with Michigan State University Extension. We'd be happy to meet with you to discuss manure storage options for your farm. If you have horses, take a took at this series of manure storage

Did you find this article useful?