The average temperature of a well is 35 to 77 F (1 to 25 C) and about 1°F for every 64 ft down after the initial 30 ft for deeper wells between 100 – 3000ft.
Well depth and the overall groundwater temperature of the well’s location are the main factors that affect a well’s temperature. Shallow wells are generally warmer, while deep wells are very cold.
Well Water Temperature
Shallow groundwater temperature varies depending on the region, but it is generally between 35 to 77 F (1 to 25 C) in the US.
For example, groundwater in Minnesota will be colder than groundwater in Florida. Well water temperature remains constant all year since the sun has little to no effect on groundwater temperature.
However, shallow wells that are only 10 to 30 ft deep are susceptible to atmospheric temperature. They usually have a temperature of about 2° to 3°F above the yearly local average water temperature.
Deeper wells that range between 100 to 3000 ft have colder waters. The water temperature goes down about 1°F for every 64 ft down after the initial 30 ft.
The well water temperature stays constant unless there is a groundwater stream that disrupts the natural flow of water. Underwater springs can influence the average temperature of well water, but this isn’t a common issue.
Keep in mind that the difference between air and groundwater temperature can make us perceive well water as colder or warmer than it is. When the weather is hot, our bodies perceive the water temperature as colder, and vice-versa.
However, if you still think the water is too hot or cold, the issue might be that the average groundwater temperature in your area has changed.
Minerals dissolve more easily in cold water. So, you may get very hard water if the well’s groundwater is very cold and has hard water minerals like calcium and magnesium.
Also, extremely cold well water will affect how much time it takes for a water heater to produce hot water. This means you’ll need to get a high-performance water heater if you’re in an area with extremely cold groundwater.
Well water cannot freeze inside the well but it can freeze as it flows through the water pipes leading to your house. The freezing is often due to cold external weather rather than the well itself being too cold.
Luckily, unfreezing frozen water pipes is quite easy.
Can Well Water Temperature Be Adjusted?
Unfortunately, the temperature of water inside a well cannot be adjusted. However, water heaters can help adjust the in-house water temperature as needed.
To adjust the temperature of your incoming well water, you’ll need to first establish the current temperature. Simply open a faucet and let it run until the water gets as hot as possible.
Once the water reaches its maximum temperature, take a small container and place a standard thermometer into it. Take note of how warm the temperature is and move over to your water heater.
Adjust the setting of your water heater to colder or warmer, depending on your preferences. Once this is done, go back and repeat the first step again. This way, you will know the exact value of the adjustment.
If you are still unable to get the desired temperature, you will have to adjust the limiter on your main valve. Since there are different types of valve, it’s a good idea to check your water heater’s manual or consult a professional.
Here are a few tips to ensure your well functions at optimal levels.
- Have your well checked by a professional on an annual basis;
- Have your water tested for dangerous substances;
- Don’t use or dispose of cleaning chemicals (hydrochloric, muriatic, phosphoric, and sulfamic acids) near your well;
- Hire a professional contractor to measure the distance between your well and nearby waste systems;
- Make sure that your well cover is a nice and snug fit;
- Have the top of the well one foot above the ground.
Groundwater temperature remains constant through seasons. The temperature is 2° to 3°F above the yearly local average water temperature for shallow wells and drops by 1°F for every 64 ft down from that point on.
You can’t change the water temperature of your well, but you can adjust the temperature of water in your house by using a water heater.