In response to the August 2014 shutdown of Toledo’s water supply due to microcystin contamination, the Ohio legislature passed Senate Bill 1, which regulates fertilizer and manure application to farm fields. Essentially, the new regulations prohibit spreading manure or fertilizer in the Lake Erie Watershed when soils are frozen, snow-covered or saturated, or if there is a more than 50% chance of at least one-half inch of rain in the following 24 hours. Exemptions apply if the fertilizer or manure is “incorporated or injected” into the soil within 24 hours or placed on a growing crop.
The goal of the law is to reduce nutrient runoff associated nuisance algae blooms in Lake Erie. The new regulations took effect in July 2015 and may not help much, in my opinion, for at least three reasons:
1. New fertilizer and manure management regulations mostly codify farm practices that are already in place;
2. The frequency and intensity of extreme precipitation events is increasing (Third National Climatologic Assessment, 2014). These flood events often occur during the growing season after fertilizers are applied;
3. Incorporation or injection into the soil often does not prevent excess nutrient runoff. Subsurface field drainage through drain tiles continues to feed nitrates and dissolved reactive phosphorus into waterbodies.
In this interview given to the Ohio Country Journal, the president of the Ohio Pork Council had this to say (bold type added):
after the water supply situation in Toledo, new regulations were inevitable. Regardless of whether livestock producers were a significant contributor to the problem or not, becoming involved in SB1 was an opportunity to be a part of the discussion and work toward common sense stewardship solutions. Working closely with legislators, we advocated for changes that would have a positive impact on the environment and are manageable for producers. At the same time, we used this opportunity to educate legislators on modern livestock production. The end result of these discussions was a bill based upon best management practices that permitted operations have been following for years, as such we were able to support the legislation….
In general, the Midwest sees heavy runoff events in late winter or early spring, prior to field work, when a combination of snowmelt, saturated soils, low rates of evapotranspiration, and heavy spring rains produces runoff and flooding. The weather does not always cooperate with the calendar and farm schedules, however, and variability and intensity of weather events appear to be on the rise, which is consistent with climate change predictions. Good summaries of the data are available here in the Proceedings of the National Academy of Science, and in a PBS interview with lead science investigator Anna Michalak.
Senate Bill 1, with its restrictions on placing fertilizer and manure on saturated or soon to be saturated ground, has created a clear incentive for farmers to increase field drainage. Ideally, they’d like to never have their fields become saturated. One way to help make this happen is to install drain tile. The original term “tile” remains even though plastic pipe has replaced the earlier clay pipe version. This equipment and installation process is relatively inexpensive and easy. A machine is pulled through a field that carves a narrow trench and inserts the pipe from rolls like those pictured above.
A local farmer told me that new tile was an “insurance policy” against the possibility of having his crops flooded out. There’s just too much water.