Black Sediments in Well Water & How to Get Rid of Black Well Water

black sediments in well water

The presence of black sediments in your well water means there is manganese in your water. These metals are soluble solids, and the only reason you can see them is that they have been oxidized hence the black sediments.

In other cases, you might notice also orange-brown sediments. This is ferric iron. Iron and manganese often occur together in groundwater, but manganese occurs in way lower concentrations as compared to iron. At first glance, these minerals appear colorless but when exposed to oxygen, the color changes to orange-brown for iron or black for manganese.

What Causes of black sediments in well water

Black sediments in well water is a common phenomenon in families that use a private well for their domestic use, majorly because well water is free and widely accessible. If you ever want to remove these minerals from your water, then I bet your reasons may not be highly inclined to medical as they would be to aesthetics.

Iron and manganese are vital for human body development; they are only however needed in small amounts. These minerals fall under the sub-group of essential minerals known as the trace minerals.

Despite their significance in the body, many may prefer to not consume them at all especially from drinking water as the metallic water taste is undesirable for both humans and animals.

For that reason, this post will address the following:-

  • Main causes of black sediments in well water.
  • Effects of black sediments in well water.
  • Effective method to remove black sediment from well water.

What would cause well water to turn black

Sediments in Water From Well

Natural sources of manganese and iron are more common in deep-seated wells where the water has been in contact with the rock for a long time. Deep and surface mining of coal can cause the black sediments in your water too.

The wells and springs in Pennsylvania have traces of these minerals. A detailed survey by Penn State from Pennsylvania discovered excessive iron concentration in 17% of the private water supplies sampled overall in the state. These minerals are even more common in the northern and western states.

Effects of Black Sperks in Water

If you live in these areas you might clearly understand just how much the water could be contaminated. These minerals cause clogging in the plumbing system.

This lowers the lifespan of the plumbing appliances such as washing machines, water heaters, and pressure tanks. You should notice also a strong metallic taste in your drinking water and also staining on utensils.

The perfect approach to this problem is analyzing the concentration level in your well by doing prior research on known water issues in your area through the EPA (Environmental Protection Agency) and through conducting an independent water test as the same water you considered safe a few years before, may currently be unsafe due to changes from the EPA standards.
A general mineral analysis should provide a list of common minerals. Remember, through analysis, the following items are important to test for:

  • Ph
  • Hardness
  • Iron
  • Manganese
  • Total Dissolved Solids

While iron causes an orange or brown stain in sinks and laundry, manganese often results in a denser black stain or solid. Owing to that, it is recommended that drinking water have no more than 0.3mg/L (0.3 parts per million) of iron and less than 0.05mg/L of manganese.

The United States’ EPA has also set a Health Advisory for manganese of 0.3mg/L. It was formed due to concerns about neurological health effects from regularly consuming water above 0.3mg/L. A Health Advisory is a non-enforceable drinking water standard that is meant to alert consumers of possible health effects from a constituent in drinking water.

Effective Methods to Remove Black Particles from Well Water

The procedure of effectively removing iron and manganese from water can be performed using several treatment processes depending on the form and concentration of the metals.

Water Testing

In water testing, you want to determine two things: the form of iron and manganese and the exact concentration of each of these metals. The form of the metals in the water could be referred to as dissolved or reduced if the well water is initially clear but turns orange-brown or black upon exposure to oxygen. In this case, they have dissolved salts; through the process of oxidation, their respective precipitates are formed.

Reduced iron and manganese exist most commonly in groundwater with a Ph less than 7.0. At times, the solid particles of the metals are immediately apparent in the well or spring water; in this case, the metals are already in their oxidized form.

This is a common situation in higher Ph water supplies (>7.0) or where oxygen is readily available to the water for instance for shallow spring water. Knowing the metal concentration determines the most economical and practical water treatment options to solve the problem.

Iron and manganese are common water pollutants and can be tested by many commercial laboratories. The most effective procedure is if you have it thoroughly tested at a DEP-accredited lab to make an overall treatment plan.

Once you have determined the concentration level of your well water, it’s time to remove these minerals.

Ion Exchange

The first step is removing them at the Point-of-Entry (POE) right before anyone uses the water. In this method, you will need to use well water softeners. These softeners use ion exchange. During the iron exchange, iron and manganese ions are exchanged with sodium ions. The manganese and iron are then removed from the water softener resin’s bed through backwashing and regeneration.

The efficiency of the water softener is dependent on the concentration, water hardness, and Ph. Water softeners are mostly recommended when the water Ph is higher than 6.7, water hardness between 3 and 20 grains per gallon (50 – 350 mg/L), and reduced iron and manganese concentration of less than 5mg/L.

In cases of too much concentration of manganese and iron, you should instead use a sediment water filter first to prevent the raw water from the well to not get into contact with air and chlorine. Air and chlorine are known to be oxidizing agents. Oxidized iron and manganese can foil the softener resin due to frequent backwashing.

Recommended: Sediment Filters for Well Water

Polyphosphate Addition

This method is suitable for water containing a reduced iron concentration of less than 2mg/L. However, this approach is ineffective in manganese removal.

Using the chemical feed pump, phosphate is fed into the water through a frequent trial and error dose adjustment to the feed pump. These dose adjustments are almost akin to administering injection by a syringe. During the process, the iron is “sequestered” or surrounded by the phosphate and is not exactly removed from the water.

This method has one drawback that the “sequestering” of the iron can influence the taste of water. This makes the water taste metallic. Adding too much phosphate into the water gives it a slippery feel. Users or consumers run the risk of suffering from diarrhea.

The polyphosphate may also get degraded by the water heater resulting in the release of sequestered iron.

Oxidizing filters

This is a slight improvement from employing polyphosphate. Oxidizing filters first oxidizes then filters both the iron and manganese. The filter consists of manganese treated greensand or other materials such as birm. With a manganese greensand filter, the filter media is treated with potassium permanganate forming a coating that oxidizes the reduced iron and manganese then filters them out of the water.

This approach also discredits the ion exchange method because it can be also be used to treat raw water through filtration.

Take note also that significant care is required in the maintenance of manganese greensand filters. This includes frequent regeneration with a potassium permanganate solution since it is consumed during oxidation of the dissolved metals. These units require regular backwashing to remove oxidized iron and manganese particles. Also, note that the potassium permanganate solution used in regeneration is highly toxic and ought to be handled carefully and stored using specific safety measures.

When properly maintained, the manganese greensand filters are by far efficient for moderate levels of both dissolved and oxidized manganese and iron. The frequency of backwashing and regeneration increases as metal concentration also increases. Keep in mind, these filters are recommended when the concentration of iron and manganese is in the range of 3 to 10mg/L.

By many standards, birm filters are similar to manganese greensand filters, except they do not require regeneration as they utilize the oxygen in the raw water to oxidize the metals. Based on that, the raw water must contain a certain level of dissolved oxygen and the Ph is at the least 6.8 for iron removal and 7.5 for manganese removal.

However, even under ideal conditions, the efficiency of manganese removal varies for birm filters. Backwashing is quite necessary for birm filters to remove the accumulating oxidized metal particles.

Fourth, this treatment method works almost similarly to oxidizing filters. This is because it employs both processes of oxidation and filtration and should be downright perfect for both manganese and iron removal. So, what is the deal-breaker?

When combined levels of iron and manganese exceed 10mg/L, this is the most effective treatment to remove manganese and iron. In this process, there is a need to oxidize the dissolved iron and manganese into their solid form. This is done by oxidizing agents such as chlorine (most common), potassium permanganate, and hydrogen peroxide. Just like in phosphate addition, a chemical feed pump is used to feed the chlorine, usually, a sodium hypochlorite solution, into the water upstream from a mixing tank or a coil of plastic pipe.

The mixing tank or plastic pipe should provide adequate contact time for the precipitates of iron and manganese to form. It is also possible, and necessary to install an activated carbon filter to remove the unpleasant taste and odors from the residual chlorine. Chlorine as an element may not be highly recommended as an oxidant because of its low Ph. To completely oxidize manganese, an oxidant of significantly high Ph is needed.

Even for this treatment method, you must maintain some discipline in maintenance. Solution tanks must be routinely refilled and mechanical filters backwashed to remove accumulated iron and manganese particles. In the case of a carbon filter, it will need to be replaced when it becomes exhausted. However, all these maintenance levels are chiefly determined by metal concentration in raw water and the amount of water used.

Iron and Manganese Filters for Well Water

What Type Of Sediment/Particles Do I Have In My Water System?

Sediments are the solid particles that settle at the bottom of a jar containing water. Sediments come in many different forms and sources and are quite easy to spot from groundwater. Apart from the conventional dirt or sand, sediments are also likely to be minerals.

To determine what type exists in your water system, you will need a more standard approach like water analysis, by which you will be looking for the Ph, water hardness (Calcium Carbonate), Total Dissolved Solids or expose them to oxidants and see if they precipitate.

1. What is the Effective Method To Use To Eliminate All Black Sediments From My Domestic Water?
Oxidation and filtration or other methods that combine these two processes. This is because soluble solids can not be removed by filtration; neither can insoluble solids be removed by oxidation. A combination of these two processes leads to topnotch results for filtered water.

2. Can I Only Depend On Certified Accredited Lab Testing Or Are There Alternative Means?

Accredited lab testing should be the ideal option. However, water testing goes way further than that. You could get yourself a home testing kit and be very concise following procedural steps towards eliminating the sediments.


Small amounts of manganese are often present with an increase in water levels. Together with other minerals such as iron and calcium, they can be deposited in the aquifer. Since well water comes from the ground, you should expect bacteria, lead, arsenic, chromium 6, mercury, manganese, radon, and other volatile organic compounds (VOCs) in your water. Needless to say, if you want to get rid of these contaminants, you will need to have a well water sediment filter – Read our Comprehensive review of the 5 Sediments Filter for Well Water.

What to do if your well water has black sediments

1. If the black sediments in water are accompanied by bad taste and unpleasant odor; testing of the water is required to ascertain the level of contaminants in the drinking water.

From our point of view, you may need to test the well water for iron, silica, bacteria, hardness, and manganese.

Alternatively, You may visit your local health or state department’s website for certified laboratory inspection.

2.In a case where you find dark brownish rocks or sand particles when you draw water from your faucet.

It might be that your well pump is way down below the set standard, or a minimum of fifteen to twenty feet high from the bottom of the well. You can resolve this problem by raising the pump shaft, thus increasing the distance between the pump shaft and the base of the well.

3. Another source of black sediments in well water might be worn out wall casing. (Casing is a lined PVC plastic, placed inside the well wall, that allows water to penetrate through, and at the same time keep out silt and sand out.)

Over time, the casing screen gadgets then allow is silt sediment, and sand to get into the well. It is advisable to contact a well driller for further confirmation

Why Do I need a sediment filter for Black Sediments?

Safer compared to tap water. The sediment filter lets you get the most out of your water without contaminants and sediments. They are approved by the FDA regulatory board and are great in their job.

Safer compared to bottled water. Bottled water to some extent is not great, despite the fact that they offer purified water. The FDA regulator board are not able to enforce strict measures on them thus your tap water being safe than bottled water.

Sees the elimination of large sediments and bacteria in water. the sediment filters are able to see the elimination of sediments of all sizes. The materials used for the elimination makes it more effective in the job.

  • Easy installation of the sediment filters The filters in the sediment filter are easy to install as they are accompanied by a manual on how to go about the whole process. Most of the filters are able to attach easily to the faucets. 
  • Environmental-friendly The sediment filter will see the reduction of the purchase of bottled water. This will eliminate the use of plastic bottles thus reduction in the disposure of plastic to the environment.
  • Less expensive This is in comparison to the water bottle which you may need to purchase from time to time. The sediment filter will eliminate the need to purchase the water bottle as clean water will readily be available at no extra cost.

When should I replace my sediment filter?

The replacement of your sediment filter ought to be done between three to six months. After this period the filter may not be able to work effectively and the presence of black sediment may be noticed in your water once again.
The change of the filter will see the effective working of the sediment filter with all contaminants being eliminated.

How do I test a sediment filter?

A working sediment filter ought to remove all visible particles matter from your water. A sediment filter should be able to eliminate the turbidity in water which causes the cloudy appearance in the water.

The cloudy appearance of water is caused by the suspension of particles in water and may cause a change in color. Sediment filters are not able to eliminate chemicals, heavy metals, bacteria, or dissolved matter from water.

Therefore, there will be no improvement in the taste of water or the smell.
Sediment filters are crucial components in the water treatment systems and eliminate all the dirt and fine particles found in water then proceed to the chemical treatment.

Why do I have dirt in my well water?

Broken pipes are the most common cause of dirty well water. The broken pipes allow dirt into the well water which can bring about odor, bad taste, and dirt in your water.

Mineral deposits are another cause for dirt in your well water. They leave behind sediment grit and grime in the well water. Filtering and cleaning can help with the elimination.

High iron levels are common in well water. The iron leaves behind red stains and the installation of a filtration system will be the remedy for this.

Organic matter is another cause of dirt in your well water. Organic matter may cause black or yellow stains on clothing. The use of chlorine may solve this issue immediately.

Waterbinary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; widely used as a solventMore (Definitions, Synonyms, Translation)


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