8 Causes for Well Water to Suddenly Turn Brown

Brown water is caused by iron and manganese, rust, poor well structure, tannins, broken-down water softener resin beads, and silt.

Thankfully, brown water is rarely a cause for concern – and it’s such a common problem in well water that there are plenty of ways to restore your water to a cleaner, clearer state.

In this guide, we’ve shared the common causes of brown or discolored water in your well, and how to get rid of brown coloration with a permanent solution.

🟤 Causes of Brown Water

We’ve listed the most common causes of brown water below.

Iron & Manganese

Ferric iron or manganese from rainwater, melting snow, or iron-bearing soil can give water a dark brown, orange, or black tinge. The corrosion of iron pipes or steel well casing can also cause dissolved iron to enter the water supply, causing it to turn brown. Iron and manganese are harmless, but they’re known to affect water’s taste and odor.

You’re most likely to notice ferric iron stains when water comes into contact with the air, which oxidizes the iron.

Looking to remove iron stains with less cost? Here are the Cheapest Ways to Remove Iron from Well Water in 2025. 👈

Rust

Rust from your water pipes is another cause of sudden brown water. If you notice that you have brown iron water in certain parts of your home but not others, you likely have an issue with rust in some of your piping. Rusty water is caused by ferrous iron, or oxidized iron, which turns water reddish-brown.

Rust may also be found in your hot water heater. If only the water from your hot tap is brown, you likely have a rusty heater.

Surface Water Seepage

If you have a shallow well hole and your water has a brown appearance and a musty or earthy odor, it’s likely caused by surface water seeping into your well. Surface water isn’t as pure as groundwater as it doesn’t filter through layers of rocks and soil before reaching your well.

Areas with shallow groundwater levels are most likely to experience surface water seepage. The brown tinge and musty smell come from minerals and organic material in the water.

Iron Bacteria

When iron and oxygen combine, iron bacteria is formed. This type of iron deposits bacterial cells and rust, creating a slimy material that sticks to the insides of piping or plumbing fixtures.

If you notice orange or reddish brown slime in your toilet bowl, bacterial iron is likely a cause of the water discoloration.

Want to completely get rid of iron bacteria? Read our Iron Bacteria Treatment Guide. 👈

Poor or Failing Well Structure

The structure of your well may also be the cause of your discolored water.

A detached well water pump may end up against the side of the well home. The well pump could also be too low in the well, causing it to suck up sediment and giving the water a brown, cloudy appearance.

Tannins

Tannins can get into your well water through decaying organic material, such as peaty soil and leaves.

When it rains, water seeps through this organic material, carrying it into the well aquifer. Tannins give water a brown, yellow, or orange color, a bitter aftertaste, and an earthy smell. While tannins aren’t dangerous to drink, they can be unpleasant in large amounts.

Worried about tannins in water? Check out our Tannin Removal Treatment Guide! 👈

Broken-Down Water Softener Resin Beads

Water softener resin beads have a lifespan of 6-10 years.

If you’ve owned your water softener for a long time and you notice your water has a black or brown tinge, this could be caused by broken-down resin beads that have been released into your water. You can fix this issue by replacing the resin bed.

Related: Causes of brown water in a softener brine (salt) tank.

Silt & Sediment

Silt and sediment are found in all well water aquifers. The majority of this silt shouldn’t be able to get into your water. However, silt can cause your water to suddenly turn brown if your well screen becomes damaged or worn. Silt and sediment cause brown, cloudy water, or dirty water.

While sediment itself isn’t a cause for concern, it may indicate that other, more harmful contaminants can enter your well, like E. Coli bacteria.