WHITE SPOTS ON WINDOWS
Why Do Windows Get White Spots in Bend?
Bend’s city tap water is actually soft, so why are the lower panes on so many Bend houses covered in white rings? Here’s what’s really causing them, how to tell spots from permanent damage and how to stop them coming back.
The Surprise: Bend City Water Is Soft
A lot of people assume Bend has hard water. For homes on City of Bend water, that’s mostly not true. The city reports hardness of roughly 0.99 to 1.46 grains per gallon and describes its water as “soft to slightly hard.” Most of it comes from Bridge Creek, a mountain surface source, with groundwater wells added in summer.
Soft water leaves far fewer minerals behind. So if city water were the whole story, you’d see very few spots. The white marks come from how and how often water hits your glass, and in some neighborhoods, from a different water source altogether.
What Actually Causes White Spots on Bend Windows
Sprinklers hitting sunny glass
This is the big one. A sprinkler head aimed a little too high wets the same lower panes every morning all summer. In Bend’s dry air and strong sun the water evaporates in minutes, and whatever little mineral it carried stays on the glass. One day of that is invisible. A hundred days in a row is a crust.
Water from other sources
Not every home in the Bend area is on city water. Private water companies like Avion and Roats draw from the Deschutes Basin aquifer, and rural homes on their own wells can have quite different mineral levels. Irrigation water from the canal system is a separate supply again. If your home isn’t on city water, ask your provider for its water quality report or test your well.
Runoff from the house itself
Water running off roofs, stucco, stone and concrete picks up minerals and dust on the way down. Streaks under a window ledge or below a gutter overflow are often this.
DIY washing that dries on the glass
Hosing windows down and letting them air dry in the sun leaves spots even with soft water. The fix is simple: dry the glass with a squeegee or towel after rinsing.
Spots or Etching? How to Tell
This matters, because spots come off and etching doesn’t.
| Check | Mineral spots | Etching |
|---|---|---|
| Run a fingernail over it | Feels slightly raised or rough | Feels smooth; the glass itself is changed |
| Wipe with a damp cloth | Looks gone while wet, returns when dry | Stays visible wet or dry |
| Try a mild vinegar solution | Softens or lifts after a few minutes | No change |
| How long it’s been there | Usually one or two seasons | Usually years of repeated wetting |
If what you have looks like etching, don’t keep scrubbing. You’ll only scratch the glass around it.
Removing Light Spots Yourself
- Rinse the window to remove loose dust and pollen, so you’re not grinding grit into the glass.
- Mix white vinegar and water about half and half in a spray bottle.
- Spray the spotted area and let it sit a few minutes. Don’t let it dry.
- Gently scrub with a soft cloth or non-scratch sponge.
- Rinse with clean water and squeegee or towel dry right away.
Test on a small corner first. Keep vinegar off natural stone sills and don’t leave it on metal frames. Skip steel wool, scouring powder and razor blades. They can leave permanent scratches, and on tempered glass a razor can do real damage.
How to Stop the Spots Coming Back
- Walk your sprinklers. Turn each zone on and watch where it lands. Lower or re-aim any head that reaches the glass. Check again after lawn work, since heads get bumped.
- Adjust after replacing heads. A new head often throws farther than the old worn one.
- Deal with runoff. Clear overflowing gutters and check drip lines above windows.
- Clean on a schedule. Spots removed after one season come off easily. Spots left for years can etch.
White Spot Questions
Does Bend have hard water?
City of Bend water is mostly soft, around 0.99 to 1.46 grains per gallon according to the city. Homes on private water systems or wells can differ, so check your provider’s report.
Why are the spots only on my lower windows?
That pattern almost always points to sprinklers. The spray reaches the bottom panes, dries in the sun and leaves minerals behind day after day.
Will a normal window cleaning remove white spots?
Light, recent spots usually come off with a proper cleaning. Heavy buildup takes extra work, and etching can’t be washed off.
Can white spots damage windows permanently?
Yes, if left long enough. Repeated wet and dry cycles can etch the surface of the glass, which is why catching them early matters.
CALL FOR WINDOW CLEANING
Spots That Won’t Come Off?
Call us and describe what you’re seeing. We’ll tell you honestly whether it’s spots or etching and what it’ll take. Serving Bend and Central Oregon.