Hot weather can dramatically increase a horse's daily water requirements. Whether your horses are kept at home, on a livery yard or grazing remote paddocks, ensuring they always have access to clean drinking water is one of the most important parts of summer horse care.
Many adult horses require significantly more water during hot weather.
Inspect troughs and water supplies several times each day during a heatwave.
Always allow extra capacity during prolonged periods of hot weather.
During hot weather, horses lose more water through sweating as they regulate their body temperature. Even horses standing quietly in the field may drink considerably more than they would during cooler conditions, particularly when grazing is sparse or they are eating mainly hay.
For owners with fields that do not have a mains water supply, heatwaves create an additional challenge. Water containers empty much faster, meaning supplies that were normally sufficient may need refilling far more frequently.
Planning ahead helps prevent horses running short of water and reduces the number of emergency trips needed during extremely hot weather. If you're unsure how much water your horse normally drinks, read our guide on How Much Water Does a Horse Drink Per Day.
Never assume yesterday's water usage will be enough today. A sudden rise in temperature can significantly increase daily water consumption, especially where several horses share the same trough.
A horse uses sweating to release body heat. As temperatures rise, particularly when humidity is also high, more fluid and electrolytes can be lost through sweat. This means water consumption may rise even when the horse is not being ridden.
An adult horse at rest may normally drink around 30 to 45 litres per day, but a horse working or sweating in summer conditions can require considerably more. Water requirements also increase when horses are eating dry hay rather than moisture-rich grass.
| Situation | Likely Effect on Water Use | Practical Action |
|---|---|---|
| Horse resting in warm weather | Consumption may rise above its normal daily intake. | Check trough levels several times and keep water cool and clean. |
| Horse eating mainly dry hay | More drinking water is usually needed than when grazing fresh grass. | Allow additional capacity and monitor droppings and drinking habits. |
| Horse exercising or sweating | Fluid and electrolyte losses can increase substantially. | Offer unrestricted fresh water and seek professional advice on electrolyte use. |
| Several horses sharing one trough | The supply may empty much faster than expected. | Increase stored capacity and make sure timid horses can reach the water. |
| Remote field without mains water | Refilling may become necessary more frequently during a heatwave. | Calculate demand in advance and keep an emergency reserve available. |
A hot or sweating horse should have access to clean drinking water. There is no sound basis for routinely withholding water until the horse has completely cooled down.
Where a horse has worked hard, sweated heavily, appears distressed or is recovering unusually slowly, stop exercising it, begin cooling measures and seek veterinary advice.
During prolonged hot weather, checking water once a day may not be enough. Trough levels, flow rates and the condition of the water can change quickly, especially where several horses share the same supply.
A simple routine makes it easier to spot problems before horses run short of water or begin showing signs of heat stress.
Early Morning
Refill tanks and troughs, check valves and clean away any contamination before temperatures rise.
Midday
Recheck water levels, shade and airflow. Make sure every horse can reach the drinking point.
Evening
Top up the supply for overnight use and inspect horses for signs of dehydration or heat stress.
Where possible, ride or work horses during the cooler parts of the day. Early morning is generally preferable to the hottest period of the afternoon.
Fields without a mains supply need extra planning during a heatwave. Water may need to be transported more often, and access can become difficult if the ground is dry, rutted or heavily used around the trough.
For more advice, read our guide on How to Supply Water to Horses in Remote Fields .
Knowing what is normal for each horse makes it easier to recognise a change. A horse that becomes unusually quiet, stops drinking or struggles to recover after exercise should be checked promptly.
Stop exercise immediately and begin cooling the horse while arranging veterinary advice where required. Do not delay cooling while waiting for the vet to arrive.
Contact your veterinary surgeon immediately if the horse appears distressed, weak, confused or unsteady, has difficulty breathing, collapses, stops sweating in hot conditions, refuses water or does not begin recovering with prompt cooling.
You should also seek advice where dehydration is suspected, recovery after exercise is unusually slow or you are uncertain whether the horse is coping with the heat.
Heat exhaustion and heat stroke can become life-threatening, so it is better to seek veterinary help early rather than waiting for symptoms to worsen.
During prolonged hot weather, horses can empty water troughs much faster than many owners expect. If your horses are grazing away from a mains water supply, it is worth calculating how much water they are likely to need before temperatures rise.
Rather than transporting numerous buckets throughout the day, many owners use a larger mobile water bowser that can be filled once and towed directly to the field. This provides a larger reserve of fresh water while reducing unnecessary journeys.
Our heavy-duty 1000 Litre Water Bowser has been designed for horse owners, livery yards and smallholdings needing a practical way to transport water to remote paddocks. With a securely mounted IBC tank and self-feeding trough, it helps keep fresh water available even during prolonged periods of hot weather.
How often should I check water during a heatwave?
At least twice a day, and more often where several horses share one trough or temperatures are exceptionally high.
Should horses always have access to water?
Yes. Horses should have continuous access to clean, fresh drinking water throughout the day and night.
Does eating hay increase water consumption?
Generally yes. Horses eating mainly hay usually require more drinking water than horses grazing fresh pasture.
Can algae grow faster during hot weather?
Yes. Warm temperatures encourage algae growth, so troughs and tanks should be inspected and cleaned more frequently.
Is one trough enough for several horses?
It depends on the group. Where dominant horses prevent others from drinking, providing additional drinking points may be beneficial.
Understand typical daily water requirements and what affects consumption.
Learn the best ways to transport and store water where there is no mains supply.
Compare different water bowser options and choose the right solution for your horses.
Discover practical advice from the Posh Pastures team on horse paddock maintenance, pasture recovery, levelling, rolling, harrowing, aeration, water management and choosing the right equipment. Browse our growing collection of expert guides to help you keep your paddocks in excellent condition throughout the year.