The midwest is often known as our nation’s “breadbasket” because of the agricultural strengths the fertile land possesses. However, in recent years, farmers throughout the midwest have faced increasing instances of flooding due to natural disasters and extreme levels of precipitation. These flooding events have caused a great deal of economic distress in agricultural communities. While these events have primarily been due to circumstances outside of farmers’ control, there are still some strategies that farmers can implement to mitigate the damage caused by flooding.
One of the most critical factors that affect agricultural flooding is the proper installation and management of drainage systems. The upkeep on such systems includes clearing debris away from channels, trash screens, and culverts as well as accumulated sediment removal, and the regular maintenance of watercourses.
Along with adequate management of drainage systems, low-grade weirs can help slow water flow, thus lessening the erosion of waterway banks and bottoms.
Farmers can also plant cover crops or leave crop residue behind in fields after the harvest. This helps to control water flow and improves infiltration. Not only that but maintaining cover crops year-round can help the soil to recover after flooding by promoting the growth of essential microorganisms that instigate nutrient cycling. Efforts to improve water infiltration can help to prevent localized flooding and replenish groundwater. Better infiltration can potentially increase the amount of water held in the soil, which enhances the availability of water for crops and reduces runoff that can erode soil and carry away nutrients.
The Department of Agriculture also offers programs that provide financial incentives for farmers willing to incorporate stream buffer zones as well as other conservation efforts such as planting trees and restoring riparian vegetation. The root systems established by riparian vegetation reduce soil erosion along stream banks, filter sediment, and soak up and store water.
Along with the use of cover crops, farmers can practice conservation tillage, contour farming, and rotational grazing to protect soil quality while promoting water flow into the soil. Any planting method that leads to at least 30% of the soil surface is covered by residue after planting is considered conservation tillage. By protecting the soil surface, it allows water to infiltrate the soil rather than becoming runoff. Along with the use of cover crops that grow deep roots, this no till strategy helps keep the soil in place. It is estimated that conservation tillage along with cover crops can increase water infiltration by 30-45%.
Another factor farmers have control over is rotating their crops. Doing so helps to keep the soil healthy. “What one crop takes out of the soil, the next one puts back in,” explains Kansas farmer, Darin Williams. Healthy soil leads to better crops and less runoff.
Similarly, the practice of contour farming also slows the water flow. By planting horizontally across the slope of the land instead of vertically, farmers can reduce the soil erosion rate up to eight times the average annual rate and soaks up twice the rainwater.
Incorporating hedgerows into farming practices can also offer increased infiltration and erosion protection. This is particularly true when they border waterways. Hedges also have the added benefit of serving as a filter for non-point pollution.
Along with keeping fences well maintained and preventing livestock from entering streams, those involved in livestock farming can also rotate the sections of the pasture being grazed periodically. Rotational grazing allows plant growth to recover in between grazings. Not only does this practice have the ability to mitigate flooding and erosion, but it also has the added benefit of improving the forage quality of their pastures.
No one strategy or combination of strategies is going to be full proof in preventing flooding; however, all of these strategies can help to minimize the damage done when flooding occurs. The strategies each farmer can employ on their land depends on the soil type and their ability to cover the costs of flood management efforts. All of these efforts by landowners and agricultural producers can help to ease the impact of flooding due to increased and extreme precipitation.