Water as a nutrient (part 3): How to clean your water lines

By Dr. Michaela Trudeau

The first step in maintaining good water quality in the barn is routine maintenance of water lines. Stagnant water or water with a low flow rate encourages the buildup of sediment and bacterial biofilms in water lines. Routine descaling and disinfecting of water lines is recommended at least twice a year. Whether a barn has good or poor water quality, cleaning the water lines is an essential piece of regular barn maintenance.

Descaling water lines

Before water lines can be disinfected, descaling should be done to remove biofilms and mineral buildup. Biofilms are layers of bacteria that bind together and form a protective coating, making them several hundred times more resistant to traditional disinfectants. Descaling water lines before disinfection will break apart these biofilms and help the disinfectants be more effective. In additional to biofilm removal, descaling is an effective method to remove mineral buildup in water lines, which is especially common on farms with hard water. Following are the proper steps for descaling water lines.

1. Select an acid product that can be used for descaling. Several commercial products are on the market, but citric acid is the most common and readily available. Check with your veterinarian or nutritionist regarding specific products.
2. After the pigs are removed from the barn, flush the water lines with water.
3. Determine how the cleaning product will be injected into the water lines. A medicator can be used, but it is important to note that a strong solution should be used to overcome the dilute injection rate of the medicator. Another option is to use a variable injection pump.
   • Target a pH between 4 and 5. A higher pH will not be as effective in descaling while a lower pH could corrode water lines.
4. Remove water nipples (or open a valve) at the end of the drinking system to drain water from the lines.
5. Resecure the nipples (or close the valve) at the end of the water line.
6. Trigger all nipples or drain and refill all pans.
7. Allow solution to sit in lines for 24 hours.
8. Flush all lines with fresh water.
9. Finish by triggering all the nipples again or refilling all pans.
10. The descaling process will often cause nipples to plug. For this reason, it may be necessary to remove and clean screens and regulators.

Sanitizing water lines

Flushing water lines with a disinfectant solution after descaling is an effective way to eliminate bacteria that could infect animals. In addition, disinfecting water lines when animals are not in the barn allows the use of a stronger disinfectant solution. Outlined below are the proper steps to sanitize water lines.

1. Flushing and sanitizing should be done without animals present in the barn.
2. Open the valve at the end of the drinking system. This is essential during disinfection, specifically with peroxide, as reactions within the water line can blow seals and damage lines.
3. Conduct an initial flush with just water to remove loose material.
4. Add the sanitizer based on manufacturer recommendations using a proportioner pump.
5. Let water and solution run through the line and drain into the pit. Watch for fizzing on the slats, end caps or the ground outside where the hoses empty.
6. Resecure the caps, nipples or valve at the end of the water line. Keep an overflow valve open overnight in case pressure builds in the lines.
7. Trigger all nipples or drain and refill all pans.
8. Allow solution to sit in the waterline for 24 to 72 hours, depending on manufacturer recommendations.
9. Thoroughly flush all lines with fresh water. When some biofilms react with disinfectants, they produce a bitter taste. Thorough flushing of waterlines will help eliminate this unpleasant taste and encourage animals to drink when they are placed in the barn.
10. Finish by triggering all the nipples or refilling all pans.

Water treatments when pigs are present

Some water treatments can be used while pigs are in the barn. These products can be used to routinely treat groups of pigs or when microbial issues arise. When using water additives with animals present, always consult your veterinarian to confirm the appropriate concentration that is safe to use.

• Organic acids: Citric acid is a common water additive that is effective as a descaling treatment and may be effective as an antimicrobial treatment as well as a nutritional additive to improve water intake. Though less common, other organic acids are available commercially for water line administration, including lactic, formic, propionic and acetic acids.
• Bleach or chlorine dioxide: Bleach (also known as sodium hypochlorite (NaOCl)) and chlorine dioxide disassociate to form HOCl when added to water. HOCl is a chlorination treatment that is effective against viruses and bacteria in the water. However, water with a high pH will inhibit bleach’s ability to disinfect.
• Hydrogen peroxide: Hydrogen peroxide is very effective at sanitizing water lines. In addition, hydrogen peroxide works faster and in a broad range of pH conditions. Hydrogen peroxide will also not leave any chemical residues or flavors in the water.

Speak with your Vita Plus nutritionist to create a water line maintenance plan for your farm.

About the author:  Dr. Michaela Trudeau joined Vita Plus as a swine nutritionist in 2020.  She grew up in Minnesota and attended the University of Minnesota to receive her bachelor’s degree in animal science with honors.  Trudeau continued her education at the University of Minnesota and received a master’s degree in animal science.  Her master’s thesis focused on the persistence of porcine coronaviruses in feed and feed ingredients.  In December 2020, Trudeau received her Ph.D. in animal science at the University of Minnesota, where her research focused on understanding the mechanisms of growth responses to various antibiotic alternatives in nursery pigs.