What to know about tiling when it comes to water quality concerns
April 27, 2017
By Sara Hewitt, Farmer, Ag Educator, & Marketing Director of Hewitt Drainage Equipment
Prinsco Customer & Guest Blogger
Would you know what agricultural drainage was if you weren’t in the industry? Water quality issues continue to dominate the headlines and agriculture is getting caught in the blame game when water pollution sources are noted.
As farmers and drainage contractors, it’s easy for us to forget that the vast majority of people don’t understand what tiling systems are and why they are used. We must remind ourselves that the simplest reason we install tile – to drain excess water off the surface of our fields in order to prevent soil loss and create root growth – is not communicated well enough with the people who are reading about, making decisions about or generally care about water quality issues.
Let’s review a few things they need to know about the benefits of tiling to grow our food supply:
- Tiling encourages water to saturate the soil more deeply, dispersing water flow from rain events over a period of many days or weeks. That is compared to water flow of surface drainage (when there is no tiling system) that may only take a few days.
- Well-drained, tiled soils, holds more water and reduce peak water flows.
- Soil and phosphorous are generally only lost through surface water. They do not leave via tile lines except in situations where tile lines are failing or surface intakes exist in a field. Data from Discovery Farms has shown that removing surface intakes and updating tile systems to corrugated plastic pipe has resulted in almost no soil loss. If there are soil or phosphorus issues in tile lines, it’s generally from clay and cement systems failing or becoming heavily damaged. When updating these tile systems, it is crucial to use correctly sized mains and proper joints to further prevent losses.
- It’s a misconception that farmers over apply nitrogen, sending it into tile line output. The ultimate goal of a farmer is to match the nitrogen application rate with the exact amount needed by crops for growth. However, it isn’t possible to completely stop the movement of nitrogen through tile systems or surface run-off. That’s because as much as we wish we could, farmers can’t control the weather, and the power of excess water cased by weather events is often when we see issues with nitrogen leaving the farm fields through tile lines rather than being utilized by the crop for growth. Even if we didn’t have tile lines, we would still lose nitrates to surface runoff.
- Farmers have new and improving methods to test for and apply only the nitrogen they need. Here are a few ways: taking deeper soil sample cores to find residual nitrogen and applying less fertilizer; eliminating fall applications, side-dressing anhydrous ammonia, or utilizing nitrogen injections alongside the planted seed as part of a variable rate application.
As we continue to discuss the benefits of tile on a farmer level, we must also work to communicate our story to consumers and the public. We must explain what tile does and how it fits into the bigger agronomic picture of soil health and water quality. We must acknowledge that there are many with concerns about water quality, but at the same time, need to appreciate the gains tile has made for crop vigor and food production.