Water quantity and quality

Guidance on providing the correct quality and quantity of water to pigs.

If performance problems arise, feed is analysed, but the water supply is often overlooked. However, 80% of the body of a newborn piglet and 55% of the body of a finisher is composed of water.

Easy, fast access to palatable water is essential to prevent dehydration, which can result in reduced feed intake, lower daily weight gain, poorer feed conversion, reduced milk production and lower weaning weights. Severe water deprivation may even result in death.

Remember, it is a legal requirement that all pigs have ready access to good quality, clean water. Defra’s code of practice for the welfare of pigs states that: 'All pigs over 2 weeks of age must have continuous access to a sufficient quantity of fresh drinking water.' 

Monitoring the water supply to a building can determine basic usage patterns. These patterns can then be used to monitor changes in drinking behaviour that may occur as a result of a blockage, leak, change of feed or environmental temperature or disease outbreak. Trials have shown that in the event of a disease outbreak, a change in water consumption occurs before clinical signs are noticed.

Important considerations

  • Ensure there is enough space for pigs at water points and that drinkers are set at a height the pigs can reach (for both the smallest and largest pigs on both entry and exit of grower pens/yards)
  • Ensure the drinkers are easily accessible (ideally, within 1–2 m of the feeders)
  • If using combined feeder and drinker stations, have additional, separate drinkers to allow pigs access when other pigs are feeding
  • Wet-fed pigs require a separate source of clean drinking water
  • Have multiple drinkers per pen (to act as a backup in case a drinker gets blocked or broken)
  • Use additional drinker points for the first few days after weaning (e.g., turkey drinkers)
  • Check all drinkers are clean and working (daily)

Water supply factsheet

Water quantity

Checking flow rates requires a large measuring jug, a watch and a minute of your time.

Check the flow rate of every nipple and bite drinker (mid-batch and between batches). Ensure you check the difference between drinkers nearest to and furthest from the supply – the variation between drinkers may surprise you. If there is a big difference between the first and last drinkers, this can indicate a blockage or problem with the water pressure.

Flow rates

Weight of pig (kg)Estimated daily requirement (l)Minimum flow rate (nipple drinkers, l/m)
Newly weaned 1.0–1.5 0.3
Up to 20 1.5–2.0 0.5–1.0
20–40 2.0–5.0 1.0–1.5
Up to 100 (finishing pigs) 5.0–6.0 1.0–1.5
Sows and gilts (pre-service and in-pig) 5.0–8.0 2.0
Sows and gilts (lactation) 15–30 2.0
Boars 5.0–8.0 2.0

Water pressure can be affected by the diameter of the washer orifice within the drinker, cleanliness of the filter, pipe diameter, deposits within the pipeline and header tank height.

Calculate pressure loss using a nomogram or an online calculator. A pump is needed if insufficient pressure is provided by gravity, ensuring a backup is available in event of a failure.

Important considerations

  • Microbiological, physical and chemical factors affect water quality. If there is any doubt concerning quality, samples should be sent for analysis
  • Water supplied from boreholes should be tested at least once a year
  • Bowl drinkers and troughs should be checked on a daily basis and cleaned when necessary
  • The complete water line, including drinkers, pipework and header tanks, should be regularly cleaned and flushed through between batches to reduce the build-up of biofilms
  • Check flow rates after flushing
  • Routinely check if pipework is clean by taking a drinker off and feeling for residue within the pipe
  • Header tanks should be covered with intact, secure lids to prevent contamination

Water quality

The water offered to pigs should be fit for human consumption. Poor water quality can negatively affect pig health.

For more information, refer to our 'acceptable drinking water parameters for pigs' guide and watch the webinar below.


Sampling water on farm is key to the early identification and management of water quality issues. We have created standard operating procedures (SOPs) and supporting guidance for collecting water samples.

Water sampling for microbiology (Farm assurance requirement)

Water sampling for microbiology, minerals, flow rate and water temperature

Case study: water sampling and cleaning

Water sampling for microbiology, minerals and flow rate 

Cleaning water systems

There are many types of water contaminants and sources of contamination. Read our 'survival time of pathogens in waters guide on counter-measures to address sources of contamination.

You might benefit from carrying out a deep clean through shock-dosing. Read our 'deep cleaning farm drinking systems' guide on biofilm and treating water systems and watch our animation which shows how to clean a water system and choose organic acids for pigs.

Survival time of pathogens in water

Deep cleaning farm drinking systems (guide)

Managing minerals

The mineral content of water can affect pig growth, health, water quality, system efficiency and unit infrastructure. Contamination of water supplies with iron and other heavy metals can cause unpleasant tastes, discolouration, pipe blockages and damage to equipment. Filters, mesh, pipework and drinker fittings regularly become blocked and the diameter of the pipework can be reduced by sedimentation. Build-up of sedimentation will lead to bacterial growth and reduce water output.

Read our 'managing mineral content of water for pigs' guide and our 'controlling iron, manganese and limescale' guide, which both discuss mineral levels and how to manage them.

Iron and manganese are important elements of pig diets. Removing these elements from the water should not affect daily intakes because pigs’ requirements are met by standard pig rations. If formulating rations for home-mixing, you should mention the change to your nutritional advisor.

Managing mineral content of water for pigs

Controlling iron, manganese and limescale in livestock water systems

Monitoring consumption and health management

Pigs with a disease behave differently to healthy pigs. These behaviours are noticeable before other symptoms become apparent.

Whole building and room consumption patterns have been found to be sensitive indicators for all-in all-out systems. Research at Newcastle University investigated the sensitivity of monitoring water for deviations in daily water intake patterns that could indicate changes in health and performance. This study demonstrated the potential of water consumption patterns to monitor pig health, even at pen level.

The relationships between body weight, liveweight gain, feed intake, temperature and group size suggest the potential for modelling water consumption to a level that delivers information on current and predictive pig health, the rate of feed intake and growth performance.

Therefore, automated water consumption monitoring could provide a sensitive tool for real-time, continuous monitoring for the early detection of disease in growing herds.

Optimising the use of antimicrobials: in-water delivery

This report includes:

  • Guidelines for drinking water quality for pigs
  • Advice on the most effective ways to clean water (both indoors and outdoors), based on the setup and level of contamination
  • What to consider when installing water systems in new and existing buildings
  • What to consider when medicating through waterlines

Download optimising the use of antimicrobials: in-water delivery

Designing a water supply system for livestock

This guide covers key issues to consider when designing a water supply system, including:

  • Infrastructure
  • Cleaning and in-water medication
  • Design of distribution and drinking systems
  • Standard values and calculations for safe distribution
  • Flow rates and pressures

Designing a water supply system for livestock

Useful links

Health and antibiotics, keeping the balance

Wach this webinar to learn more about the importance of water supply and water quality. It includes a case study on moving from in-feed medication to in-water medication.

Health and antibiotics, keeping the balance (Part 2: Water)

Code of practice for the welfare of pigs