By: Patrick Troyer, Paulding SWCD
At the Paulding Soil & Water Conservation District (SWCD), we seek to ensure that the residents and producers of Paulding County are well informed of the best management practices (BMPs) that our office can assist with as we seek to preserve and protect the natural resources of Paulding County. We will be running another series that this time focuses on these BMPs. Articles in this series will explain what the practice is, how it helps, and how Paulding SWCD can assist you with it. There are a number of practices for us to discuss so stay with us to learn about them all. This week we will focus on one practice that is utilized in Paulding County called a blind inlet.
Also known as a French drain, blind inlets are structures that are strategically located at the lowest point of a farmed depression to reduce the amount of sediment, fertilizers, or pesticides that could move through a tile outlet. According to Ohio State University, this practice is located at the lowest elevation of a field where crop loss or the ability to move equipment across the soil due to prolonged saturation of the soil. A blind inlet includes gravel that is backfilled around a perforated pipe located two inches above the bottom of the excavation site in a conduit style layout. The gravel acts as a storage component that helps to filter water passing through laterally through the soil and vertically through a one-foot layer of sandy material called a pit run, according to Ohio State.
Located between the sidewalls of the excavation pit and the pit run material is a geotextile material, a permeable fabric that helps to prevent clogging of the perforated drainpipe of sediment. Water from runoff from the enclosed depression of the blind inlet passes through the filter material is slowed down as it makes its way to the tile outlet. By slowing the water down, sediment, nutrients and pesticides can be filtered out before exiting the field. Ensuring the water leaving a field is as clean as possible goes a long way when we consider the overall water quality of our area that can be improved by one practice such as a blind inlet.
For design of a blind inlet consult the Paulding SWCD office for the proper sizing and construction specifications as these are the most critical components to make sure a blind inlet works for you. Blind inlets are strong enough to withstand the traffic of farm machinery. Ohio State University cautions that this practice is not intended to improve drainage efficiency and that a functioning downstream drainage network will be needed along with a blind inlet.
Many are likely wanting to know what kind of cost is involved with installing this practice. Costs are going to vary based on the availability of the materials needed along with the size of the blind inlet that will be required for the specific location. According to Ohio State University, contractors estimate a blind inlet can be fully installed for $1,500 to $3,000. Once a blind inlet is installed, there is no routine maintenance that is required but there should be caution employed during any deep tillage operations that could tear the geotextile fabric that is installed with this practice.
In a traditional tile riser system, water is passing through the tile system with no filtration involved. With a blind inlet, water is percolating through layers of soil and rock before it enters the tile system, thus the water is filtered. Tiles are less likely to be plugged with debris along with reduction in the discharge of pollutants such as nutrients, pesticides, or sediment that all can greatly reduce water quality. As we all know, water quality is a very important topic at this time.
A properly installed blind inlet will have an estimated life span of around ten years. It is advised to utilize a complete no-till system in order to keep soil disturbance at a minimum and get the most life out of the inlet. This practice is best installed during dry or frozen soil conditions, as this will have minimal effect on compaction of the area around the blind inlet. How effective is a blind inlet? Ohio State University cites studies conducted in Northeast Indiana that showed blind inlets decrease sediment loads in the water moving through by 79% and phosphorous by 78% compared to a traditional tile rise.
If you think this is a practice that will work for you and your operation, be sure to give us a call or stop by the Paulding SWCD office and see how we can help you today. Stay tuned for further installments in our “Conservation Practices” series for more practices that can help to preserve and protect the natural resources of Paulding County.
