If you live in an area where your well supplies your drinking water, chances are after heavy rainfall, your drinking water may appear cloudy or brownish-yellow. This can be unattractive for a homeowner to look at, but understanding how rainwater affects the groundwater and therefore wells will help with finding ways to address and prevent this issue. Heavy rainfall affects many rural and some suburban communities, therefore I’m sure you are asking, “Why is my well water yellow?”, along with many other homeowners in your area who have also asked themselves the same question.
While discolouration of well water is not indicative of the safety of your drinking water, it often indicates the potential for contamination or mechanical malfunction. Whether you have new debris floating in your water supply, a persistent cloudy haze that seems to hang in the air, or a yellow tint; finding out the source of these issues is the first step in safeguarding your family’s health. In many cases, performing appropriate testing on a regular basis will bring back the clarity of your water supply; however, having an understanding of each possible cause will enable you to take better action following any future storm events that result in similar occurrences.
It is imperative for homeowners to take a cautious and educated approach in responding to discolored water. Storms can introduce multiple aspects of environmental change to our groundwater; the increase of surface water runoff produces raw sediments that may enter into our well; therefore; a proactive approach in the form of regular well inspections and testings of well water may safeguard the quality of your well water and provide you with the peace of mind needed to enjoy an uninterrupted water supply.
Surface Water Infiltration
After heavy rain, the most frequent source of cloudy, discoloured water from your well is likely due to surface water being absorbed into the ground. Rainfall is usually greater than the ground can soak up in many instances, resulting in water accumulating on the earth’s surface and flowing away (runoff). When this occurs, and if there are problems with the well cap or its well casing, rainwater may run down into the well and bring with it surface contaminants such as microbe-containing bacteria, dissolved fertilisers, pesticides, and animal faecal matter. All these contaminants tend to create cloudy water, and they can also create potential health hazards. Therefore, it is imperative to have a good-quality seal and to properly maintain the well cap and casing.
Mineral Disturbances
Minerals may dissolve in the soil surrounding the well during a rainstorm because of the addition of water from the rainstorm (increasing groundwater level). Once the surface water gets to the atmosphere, it starts to oxidise. This oxidation produces yellow-orange or brown colouration in water. These minerals in higher quantities are not likely to be harmful when drinking; however, the increased amounts can lead to problems like staining of plumbing, laundry, and dishes, and give the water a metallic taste.
Bacterial Contamination
Severe weather, including heavy rainfall, flooding, and other natural disasters, may result in sewer systems becoming overloaded and/or bacterial contaminants leaching into both the environment and groundwater supplies. If a private well or source of drinking water contains E. Coli or other pathogenic microorganisms, they will likely contaminate the water supply if the water source does not have proper construction or if there are bypassed protective layers of soil that provide natural protection for groundwater supplies. Bacterial contamination may pose a risk to consumers of that water, thus resulting in health threats such as gastrointestinal illnesses and/or other more serious bacterial infections. If there is any suspicion of contamination, drinking the water should cease, and the water should be tested for contamination immediately. A publication by the U.S. Environmental Protection Agency provides a detailed reference regarding the protection of private wells and their associated supplies from various types of contaminants, including bacteria.
Sediment Disturbance
Sediment that settles on the bottom of the well will accumulate and, when heavy rain happens, there is an increase in groundwater flow and turbulence, which can cause sediment to be disturbed and suspended in the well. When this occurs, the water may appear to be cloudy or brown within a short period of time following storm events. If sediment continues to be present in the well, this may indicate that the well screen and/or casing needs to be repaired by a qualified well technician.
Tannins from Organic Matter
Decomposing organic materials, including vegetation and leaves, can contribute to the production of tannins in groundwater. This is especially true during heavy rains when the influx of surface water into a well dramatically increases. Tannins are substances that are produced naturally by plants, causing water to appear yellowish or tea-coloured, with an earthy aftertaste, which may be off-putting to consumers. Although tannins usually pose no health risks, they can detract from the attractiveness of the water because of the degree of turbidity they produce and the flavour they impart. Tannins can be effectively removed using specialised filtration methods designed specifically for the removal of organic matter.
Plumbing Issues
Sometimes, it isn’t necessarily the well that causes the water to be discolored but rather the plumbing leading from the well into the bathroom, kitchen, etc. The source of the problem can often come from plumbing that has corroded over time due to exposure to moisture when they are left unused for a long period or when water collects somewhere in the pipe. Oftentimes, if there are only certain faucets or other fixtures that show signs of discoloration, this indicates that the source is most likely somewhere in your plumbing system as opposed to being a problem with your well. One of the best ways to remedy this type of problem is to flush your plumbing system and/or replace any old and corroded fixtures.
When to Seek Professional Help
It is advisable to get in touch with an experienced water quality expert if you observe any discoloration or unusual smells or tastes in your well water. This type of expert will offer a thorough examination of your entire well system including an assessment of the quality of your water. After conducting this comprehensive assessment of your well and obtaining an analysis of the quality of your water, the water quality expert will advise you on how to repair your well system, as well as recommend treatment options that will help you resolve the identified issues through testing. The most important thing is to ensure that your drinking water is safe and clean.
