Narrow Slot vs. Sock in the Red River Valley

January 19, 2012

By Jamie Duininck, Vice President of Sales, Prinsco

As you probably know, agriculture drainage in the Red River Valley has an extra challenge as compared to the rest of the Midwest. Soil conditions can vary widely throughout the area, even within a few acres.

That’s because the Red River Valley was once part of the world’s largest glacial lakes – Lake Agassiz. This expansive body of water once covered much of Manitoba, northwestern Ontario, northern Minnesota, eastern North Dakota, and Saskatchewan. When the lake finally drained, it left behind a widely varied landscape that included sand, clay, silt and rich black dirt.

With such a vast amount of soil variance, it can be very challenging to determine which type of pipe should be used in your agricultural drainage system. Farmers and contractors are often confused about when to use standard single-wall pipe, narrow slot pipe or sock pipe.

Here are a few rules of thumb, especially for the Red River Valley:

If you know that your soils are very sandy and you are thinking about narrow slot pipe versus sock pipe, take several soil samples throughout the field at the depth you install your laterals and have them analyzed. The test will cost about $25 and take only a day or two to complete. That’s a pretty cheap investment for the peace of mind and assurance that your drainage system will work properly for generations to come. 
Yes, sock pipe does cost more! But, if it is the right product for the job, then I strongly encourage you to use it! Just remember that the extra expense of sock is only a small portion of your overall project cost and can potentially save you thousands of dollars down the road if you need to come back to that same field because of sand-clogged pipe.

3. USE THE 25% RULE*
When considering sock versus narrow slot pipe, remember this­ – if your soils are less than 25% clay, they probably need sock pipe. Also, if all the sand partials are the same size making it difficult for those partials to stick together, this may be another indication that you need sock pipe.

Both narrow slot and sock pipe are available from almost all pipe manufacturers. It is up to the contractor and the landowner to know their soils and be confident with their decision about what products to use. For additional help or advice, contact one of our experienced Prinsco sales representatives today!

*See for more detailed information about the 25% rule and other drainage design issues

Categories: Agriculture