If you have access to groundwater through a borewell, it may seem an excellent way to supplement your garden’s water requirements. It may even be your primary water source if you can’t access public water supplies easily.
Bore water can be used to water vegetables if the salinity level is below 1000 ppm. Bore water may also have unsuitable mineral, metal, and bacteria levels. If so, treat your bore water before watering vegetables with it.
Bore water is primarily used for irrigation, but if the salinity is too high, the water will have to be treated or redirected. This article will take you through what bore water is, why it may be unsuitable, and how to purify it for watering your vegetables, so read on!
Understanding Bore Water and Its Characteristics
Bore water refers to groundwater accessed through a well dug or drilled into areas where the surface water has saturated the ground to fill underground aquifers.
Simply put, rainwater and other excess surface water soak through the different soil layers deep into the ground. You can access this water by creating a bore well by drilling into the ground down to where the water has collected.
The quality of bore water varies dramatically from region to region.
Bore water from various regions has the following characteristics:
- Different concentrations of salts and minerals
- Varying pH values
- May or may not have contaminants
Bore water should be about as pure as rainwater since it is made of rainwater seeping through the ground. Most bacteria are filtered out through this process as well. However, increasing levels of groundwater pollution are affecting the quality of bore water.
Pollution may seep into aquifers, especially industrial pollution, or runoffs of agricultural products like inorganic fertilizers and pesticides. Air pollution has been steadily affecting the quality of rain, and as rainwater becomes less potable (safe to drink), the quality of groundwater is similarly affected.
Depending on the area, tap water may be safer than bore water to water vegetables and other edible plants. Furthermore, sensitive plants like moss, which should never be watered with tap water, shouldn’t receive bore water either.
You can learn more about the watering requirements of moss in this article: Should You Water Moss With Tap Water?
As we’ve just discussed, bore water would ideally be as pure as rainwater. But with rainwater becoming less potable and human activities affecting the quality of the ground, bore water is affected as well.
The quality of bore water can vary tremendously. It may be fresh and perfectly potable in some regions yet extremely unsuitable for any usage except industrial processes in others.
Here are some common issues with using bore water, even for non-potable purposes.
High Levels of Salinity
Salinity levels refer to the concentration of salt in the water. The salinity of bore water may be affected by the composition of the rock that it passes through and potential contamination from seawater.
If bore water has too much salt, like New Mexico’s groundwater, it becomes unusable for most domestic uses. Anything above 1000 parts per million is too salty for use.
The Hardness of the Water
How hard water is depends on the concentration of minerals and salts like calcium and magnesium. High percentages of calcium and magnesium are detrimental to plants because they affect their ability to draw water from the ground.
Extreme pH Values
The ideal pH value of water for domestic use is between 6 to 8.5. However, bore water may range from extremely alkaline, aka hard water, to extremely acidic, with pH values dropping below 5. Both extremes are bad for vegetables.
High Concentration of Metals
Bore water may have a high concentration of metals like iron, cadmium, copper, lead, and aluminum. All of these metals accumulate due to agricultural or industrial contaminants. In high concentrations, they will affect the root growth and productivity of vegetables.
Bacteria and Other Pathogens
Common bacteria like salmonella and E.coli have been found in bore water, and if used without treatment, the water will infect the vegetables. On consumption, the bacteria will be passed on and infect people, leading to disease outbreaks.
Apart from those mentioned above, other contaminants like oil, effluents from factories, arsenic, and other poisonous chemicals may be present in bore water. Using contaminated bore water to water vegetables will contaminate the vegetables and make them unsafe for consumption.
The Importance of Testing to Ensure Water Quality
If you suspect that your bore water might be contaminated in some way, then you should ensure that a sample is collected and tested. If your water looks cloudy, changes color, or smells odd in any way, you should send it to a professional laboratory for testing.
The primary tests for bore water are for the salinity levels, as that is the most common problem associated with bore water usability. Once you get the results, you can use this handy table by the WateReuse Foundation to interpret them.
pH values and minerals will be detected in most basic tests, but more in-depth irrigation water tests will also test for the concentration of metals in the water.
Testing for bacteria and other contaminants is usually only done if you raise a specific concern and will be different from standard irrigation water tests. However, if you notice even the slightest sign of contaminants, ensure that you get your bore water tested.
All testing should be carried out in an independent laboratory that meets the FDA’s guidelines, and the sample of your bore water should be collected by trained professionals.
Your bore water may not be suitable for watering vegetables right out of the ground, but you can make it more suitable by purifying it.
Here are some ways to purify your bore water for non-drinking domestic use:
Boiling your bore water is one of the simplest ways to reduce the concentration of salts and kill bacteria and other disease-causing pathogens.
Reverse Osmosis Filtration
Reverse osmosis is one of the best filtration systems for bore water and makes it safe for all uses, including drinking.
Activated charcoal absorbs most contaminants and is especially useful in filtering out hydrogen sulfide, a common contaminant in bore water.
Adjust the pH Value
Highly alkaline bore water can be treated with an injection of acids like sulfuric acids in small quantities till the pH value is neutralized. Acidic water can be neutralized with something alkaline, like lime.
Purifying bore water doesn’t have to be complicated, especially if your primary concerns are salinity and pH value.
Benefits of Bore Water for Vegetable Irrigation
So long as your bore water is safe and free from contaminants, it can be an excellent option for watering your vegetables. Bore water and spring water both come from rainwater effectively processed through the ground, and rainwater is still one of the best ways to irrigate plants.
Here are some advantages of watering vegetables with bore water:
Supplements Plant Micronutrients
Usable bore water will still have some percentage of minerals and salts, but in quantities that are beneficial to plants. Calcium, magnesium, iron, and copper are all plant micronutrients and are necessary for plants. They are only detrimental in large quantities.
Bore water with safe levels of minerals supplements your vegetables with micronutrients and helps them increase yields.
Nitrates to Help Plant Growth
One of the biggest advantages of bore water is that it contains nitrates, a natural source of nitrogen. Nitrogen is one of the macronutrients needed for plant growth, so the nitrates in bore water will help your vegetables grow.
Affordable and Accessible
In areas with bore water, this water source is often cheaper and more accessible than the main governmental water supply.
When using bore water to irrigate your garden vegetables, ensure to deeply water the soil with filtered water every month to avoid salt buildup. It’s also best to use rainwater or pure water every time you fertilize your vegetables to dilute the nutrients in the soil to safe levels.
You can learn more about the suitability of spring water for watering plants in my article that explores if you can use spring water for carnivorous plants: Can You Water Carnivorous Plants With Spring Water?
You can water vegetables with bore water as long as it’s fresh groundwater. The water may be unusable due to high salinity or extreme pH values. Other contaminants may also render the bore water unusable.
You can treat unusable bore water to use it for non-drinking purposes by boiling it, filtering it through reverse osmosis or activated charcoal, and adjusting the pH value.