This past fall we installed our very first drain tile, which was a culmination of a few years’ worth of planning, research, work and waiting on wetland determination (which is still an ongoing process). We were able to see a bit of what this tile can do even within just months of having installed it. This year we plan to put in more tile and look forward to seeing the benefits of this project on our farm.
What is Drain Tile?
The drain tile we are laying in our fields is a perforated pipe just like many people use around the foundations of their homes to keep a basement from flooding, for example.
It is corrugated plastic with little perforations in it. When the water table raises above the tile pipe, the water seeps into the pipe through the perforations, then runs through the tile and out an exit point, like this:
The drain tile can only take in water as a result of the water table rising; it does not drain water that is existing on the surface of the field. Tile is complimentary to surface drainage and not a replacement.
How is it Installed?
This is a picture of a topography map on display inside the cab of the tractor that is used for tile installation:
Maps such as this one are prepared in advance and help determine how and where to lay the tile.
Essentially, a trench is dug and the tile is laid using the equipment shown in the photo above. Here are a couple of videos that show the process in action.
A closer look at some of the tile:
Many farmers use contractors to plan, prepare and install tile. Through much work and preparation, we have been able to lay about 50,000 feet of tile on our own, but we are looking toward also outsourcing some work as well. There are many more acres we would like to mitigate using drain tile and anticipate using a combination of in-house and contract labor.
Why Use Drain Tile?
Drain tiling is essentially a water management tool. The idea is not that we will necessarily drain new land, but rather that we can lower the water table in wet areas of a field so that when a substantial rainfall occurs or a large spring melt of snow, the overrun of water has a place to go.
In the Red River Valley, water outlets can be controlled so that tile would not run if the river is at a high level. Agriculture will likely become part of a solution to keep cities from flooding, as we have seen with the Missouri and the Red Rivers in North Dakota.
The intention is that in the fall, the tile would allow water to run out of the field so that the soil in the field can hold water during the wet springtime and avoid flooding. In our area, a lot of the water does not leave the immediate region. We would like to use the technology available to move from having three or four areas in a field that drown out crops and bring them together to create one sustainable wetland.
Another major benefit of tile drainage is that it cures soil erosion. When water has to move on top of the soil, it is always taking soil and minerals along with it. This is not something we want to happen. Preventing such erosion from happening helps retain soil minerals and overall soil quality.
Our Progress Thus Far
Our first project was done behind our main shop area in Hurdsfield. The land around Hurdsfield has many hills, so there could certainly be cases where only 80 acres out of a quarter would be worth tiling and many might be less since the water will flow on its own when it is wet enough. Of course there is that negative impact of eroding soil and nutrients. On the ground behind our shop we installed 18,000 feet of tile pipe on approximately 30 acres. The field was dry, but the ground we tiled was surface drained and where the water would drain to was still wet so the tile ran within 12 hours. A couple weeks after the tile was installed, we received two inches of rain. The soil had room to hold it now, and we took that in without the surface run off and ponding. A week later we received another two inches of rain. This time we did have some ponding, but the ponds were gone a day and a half after the rain stopped. At this point, Chad had taken a 5 gallon pail out to measure our out flows of the tile lines.
We took water quality samples from the outlet and sent them to Agvise. We had already applied the nitrogen for next year's crop before the seven inches of rainfall came. The results of the sample came back as drinking water quality. The report stated that the drinking water quality standard is 10 parts per million (ppm) of nitrates. An adult human can tolerate 100 ppm, but the standard is less for infants and some other sects of the population.
If certain levels of salts, nitrates, etc. are present in the water that is drained using the tile, it is because those are leachable problems within the soil. Tile is purposefully installed in the areas of the field that are plagued with these issues which is why we see crop production loss on some of that land. Given some time, the water running out of the tile will improve over even what it is today. There may be cause for concern if every acre could be tiled in one year, but that is not possible, and the length of time before results will improve is not long. Given what we have researched and seen thus far on our own farm, we believe the truth about tile is that it is safe, responsible, and sustainable for agriculture and our environment. In our case, the water in these fields are all drained by surface drains and still will do so in a large rainfall event; however, now we can combat erosion and manage the water table to a certain degree.
Some Challenges and a Look Ahead
We have found the wetland determination process to be a long and daunting one. Waiting on the NRCS to address our determinations has been very frustrating. We are still in the process of waiting on more determinations, but we will be able and ready to proceed with more tiling projects this spring. We are looking forward to working with some new features such as Variable Frequency Drive (VFD) pumps, which operate depending upon the amount of water coming in so as to allow some control over the release of the water. Ultimately, our goal is to improve the health of our soil and improve production. We cannot produce crops on unhealthy soil, so we make every effort to ensure the health and quality of the very ground our livelihood is built upon.
Chad, how long did it take for your determinations to come back from NRCS? We have been waiting over two years now. They visited the field two years ago... the application was put much before that. Can a grower do anything to speed up the process?ReplyDelete