ZIP Code 95987
Colusa County, California — Williams
What This Means
Colusa County, California has hard water, estimated at 180 mg/L (PPM). Hard water causes noticeable mineral scale on faucets, showerheads, and inside water heaters. You may notice spots on dishes, stiff laundry, and dry skin or hair. A water softener is recommended to protect your plumbing and appliances.
What You Should Do
Hardness Details
| ZIP Code | 95987 |
| County | Colusa |
| City | Williams |
| State | California (CA) |
| Hardness (PPM) | 180 mg/L — Hard |
| Hardness (GPG) | 10.5 grains/gallon |
| Classification | 121 - 180 mg/L |
Source: USGS Water Quality Portal, county-level median
Your Water Utility
| Utility Name | CITY OF WILLIAMS |
| System ID | CA0610004 |
| Water Source | Ground water |
ⓘ Your utility may treat water before delivery, which can change hardness levels. Check your utility's annual Consumer Confidence Report (CCR) for exact hardness values.
USGS Monitoring Data
| Monitoring Stations | 196 |
| Range | 7.7 – 1250 mg/L |
| Most Recent Data | 2025 |
| Data Quality | Measured |
Source: USGS Water Quality Portal
Effects at 180 PPM Hardness
At 180 ppm, expect noticeable effects: soap scum buildup on fixtures and shower doors, cloudy spots on dishes, dry skin and hair after bathing, and reduced water heater efficiency. Laundry may feel stiff, and you will likely need more detergent for effective cleaning.
Is Williams Water Safe to Drink?
Yes. Hard water at 180 ppm in Williams is safe to drink. The calcium and magnesium that make water hard are actually essential minerals your body needs daily. The World Health Organization confirms there are no health-based guidelines for water hardness.
You may notice a slightly mineral or chalky taste at this hardness level. A drinking water filter (pitcher-style carbon filter or under-sink reverse osmosis system) can improve taste if desired, though the water remains perfectly safe to drink unfiltered.
Your Water vs National Average
Williams water at 180 ppm is 80% harder than the US average of approximately 100 ppm. This means your area has harder water than most of the country, and a water softener would provide more benefit here than in an average American home.
Best Solution for 180 PPM Water
A whole-house water softener is recommended ($800–2,500 installed). At 180 ppm, an ion exchange softener will protect your water heater, dishwasher, and plumbing from scale buildup. You will also notice improved skin and hair health, softer laundry, and reduced soap and detergent usage. The system typically pays for itself within 3–5 years through energy savings and extended appliance life.
Colusa County Water Hardness Map
Soft Moderate Hard Very Hard
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Frequently Asked Questions
What is the water hardness for ZIP code 95987?
ZIP code 95987 is in Colusa County, California, with estimated water hardness of 180 mg/L (10.5 GPG), classified as hard. The area is served by CITY OF WILLIAMS.
Do I need a water softener in 95987?
With hard water at 180 PPM, a water softener is recommended to protect your plumbing and appliances from mineral scale buildup.
What county is ZIP code 95987 in?
ZIP code 95987 is in Colusa County, California (CA).
Is Williams water hard or soft?
Williams water is classified as hard with an estimated hardness of 180 ppm (10.5 GPG). This is hard water — you may notice scale buildup, dry skin, and spots on dishes.
Is hard water in 95987 safe to drink?
Yes, hard water in ZIP code 95987 at 180 ppm is safe to drink. The calcium and magnesium minerals are actually beneficial for your health. You may notice a slightly mineral taste. A simple carbon or reverse osmosis filter can improve taste if desired, but the water is perfectly safe unfiltered.
Will 180 PPM water damage my appliances?
At 180 ppm (hard), scale buildup will reduce water heater efficiency and can shorten appliance lifespan. A water softener is recommended to protect your investment.
Do I need a water softener in Colusa County?
Yes — Colusa County has hard water at 180 ppm. A water softener ($800-2,500 installed) is recommended to protect plumbing and appliances.
Is Williams water OK for aquariums and plants?
Use caution. At 180 ppm, soft-water fish species may struggle. Consider using filtered water for aquariums. For plants, hard water can raise soil pH — use rainwater or filtered water for acid-loving species.