Water Softeners Covina, CA | Sized to Your Supplier's Hardness

Do you need a water softener in Covina?

You do not need one: Covina's water meets state and federal standards, hard water is not considered a health risk, and a softener is a comfort and maintenance choice, not a safety fix.

That said, Covina water is hard by any common scale. The City of Covina's 2025 Consumer Confidence Report lists an average hardness of 230 mg/L, with a range of 190 to 280 mg/L. North Dakota State University's extension service classifies water above 180 mg/L (about 10.5 grains per gallon) as very hard. You see it as white crust on showerheads, spots on glasses, soap that does not lather well and scale inside water heaters.

The Vermont Department of Health puts it simply: hard water is not considered a health risk, there is no health standard for hardness, and the calcium and magnesium in it can add to your mineral intake. The problems are nuisance problems: scale, soap scum, gray laundry and shorter lives for faucet cartridges, toilet fill valves and water heaters.

So the honest question is whether those nuisances cost you enough, in parts, cleaning time and appliance life, to justify the cost of a softener plus its salt, water and upkeep. For some households the answer is yes. For many, a cheaper step like descaling the water heater on schedule or cleaning aerators does enough.

A softener is often worth it when

You have a tankless water heater that scales up, you replace faucet cartridges and fill valves often, you plan a reverse osmosis system under the sink, or the crust and spotting truly bother you every day.

You can often skip it when

You rent and cannot alter the plumbing, someone in the home must limit sodium and you do not want a separate drinking tap, you have nowhere to put it with a drain and outlet, or the scale is a minor annoyance you handle with vinegar.

Which water supplier serves your Covina address

Six different water suppliers serve parts of Covina, so your hardness depends on your address, and the name printed on your water bill tells you which one you have.

The City of Covina's purveyor list names six suppliers. The City's own Water Division, at 534 N Barranca Ave, serves about 33,300 people through about 8,500 connections and about 102 miles of mains. The other five serve the rest. Neighbors on the same street usually share a supplier, but not always near the edges of a service area, so check your own bill.

Water suppliers serving parts of Covina and what we know about their hardness
Supplier (name on the bill)	Customer phone (plain text)	Reported hardness
City of Covina Water Division	626-384-5220	230 mg/L average, range 190 to 280 (about 13.5 gpg), 2025 report
Golden State Water, San Dimas system	800-999-4033	About 205 mg/L average (about 12 gpg), range about 5 to 18 gpg, 2025 data
Suburban Water Systems	626-543-2640	See Suburban's current water quality report
Valencia Heights Water Company	626-332-8935	See Valencia Heights' current water quality report
Azusa Light & Water	626-812-5063	See Azusa's current water quality report
Glendora Water	626-852-4838	See Glendora's current water quality report

We list numbers only for the two reports we have read ourselves. Suppliers publish a yearly Consumer Confidence Report, and the hardness line is usually in the table of unregulated or secondary constituents. Look for "Hardness (as CaCO3)" in mg/L, or a figure in grains per gallon. Our Covina water suppliers and hardness guide goes supplier by supplier, and our who to call guide covers billing and outage contacts.

Why the range matters as much as the average

Golden State Water's San Dimas report shows a range of about 5 to 18 grains per gallon. That system blends treated groundwater from the Main San Gabriel Basin, local surface water wholesaled by Covina Valley Water Company, and imported water from the Colorado River and the State Water Project. Blends shift, and so does hardness. The City's supply is mostly filtered San Gabriel River water from Covina Valley Water Company, with Metropolitan Water District water from the Weymouth plant used in February, March, June, September, October and November of 2025. Its range was narrower, 190 to 280 mg/L. A softener sized for the average can run out of capacity in a high month, so we size toward the upper part of the range.

What 230 mg/L of hardness means in grains per gallon

To turn mg/L into grains per gallon, divide by about 17.1, so the City's 230 mg/L average is about 13.5 grains per gallon and its 280 mg/L high is about 16.4.

Golden State Water's report defines one grain per gallon as 17.1 mg/L of hardness and notes that grains per gallon are often used for sizing household softeners. Softener makers rate their units in grains, so this is the number you will use. Water reports usually list hardness "as calcium carbonate," which rolls calcium and magnesium into one figure. The City's report lists calcium at 56 mg/L and magnesium at 22 mg/L on average in 2025.

Hardness classes from NDSU Extension, with where Covina supplies fall
Class	mg/L as CaCO3	Grains per gallon	Covina examples
Soft	Under 17	Under 1.0	None reported
Slightly hard	17 to 60	1.0 to 3.5	None reported
Moderately hard	61 to 120	3.5 to 7.0	Low end of Golden State's San Dimas range
Hard	121 to 180	7.0 to 10.5	Parts of Golden State's range
Very hard	Above 180	Above 10.5	City of Covina average (230) and Golden State average (205)

City hardness, 2025: 230 mg/L average, 190 to 280 range
Calcium: 56 mg/L average
Magnesium: 22 mg/L average
Sodium: 89 mg/L average, before any softening
Total dissolved solids: 540 mg/L average, 460 to 620 range
pH: 8.2 average

The report also says the City's water met all state and federal drinking water standards in 2025. Hardness is listed as an unregulated constituent: it comes from natural deposits, not from a treatment problem.

Softener vs filter vs scale control: which one does what

A salt-based softener is the only one of the three that removes hardness; a filter treats things like taste and chlorine, and a salt-free scale control unit leaves the minerals in the water and tries to keep them from sticking.

Salt-based softener (ion exchange)

Swaps calcium and magnesium for sodium (or potassium) on a resin bed
Actually removes hardness, so soap lathers and scale stops forming
Needs salt, a drain for the brine and usually an outlet
Adds sodium to the water it treats
Best fit for very hard water, tankless heaters and RO pre-treatment

Filter (carbon, sediment or RO)

Carbon and sediment filters are sold for taste, odor, chlorine and grit
Check each product's certification for what it is certified to reduce
An under-sink reverse osmosis unit treats drinking water at one tap
Hard water scales RO membranes, per the Vermont Department of Health
Does not soften the whole house

Salt-free scale control (such as TAC)

Does not remove calcium or magnesium
Aims to keep minerals from forming hard scale on surfaces
No salt, no brine discharge, no added sodium
Soap and spotting behave like hard water, because the water still is hard
Much of the published testing is sponsored by makers

How a softener works

NDSU Extension explains it this way: as hard water passes through the resin, the larger calcium and magnesium ions displace the smaller sodium ions held loosely on the resin. The hardness stays behind and sodium goes into your water. When the resin is full, the softener backflushes with a salt brine to recharge, and that brine goes down the drain.

What a filter does in Covina water

The City disinfects its water with chlorine or chloramines before delivery, and its main supplier also uses ultraviolet light. Some people want to reduce the chlorine taste at the kitchen tap, and a carbon filter is the usual tool for that. It is a different job from softening. If a salesperson tells you a carbon filter will stop scale, ask for the certification that says so.

Reverse osmosis needs softer water

The Vermont Department of Health says hard water can scale reverse osmosis membranes and UV bulbs, and that a common guideline is to keep hardness at or below about 120 to 170 mg/L (7 to 10 grains per gallon) ahead of them, though membrane makers may set their own limits. Covina City water averages 230 mg/L, well above that. If you want RO drinking water, plan for either a softener ahead of it or more frequent membrane changes.

What salt-free scale control is

Template assisted crystallization (TAC) is the best known salt-free method. A continuing education course sponsored by Watts, a company that sells TAC products, describes it as reducing scale "without removing or adding anything to the water": the minerals form tiny crystals that stay suspended instead of sticking to pipes and heater surfaces. Because the source is a maker, read its claims with that in mind. What is not in dispute is that the hardness is still in the water.

How to size a water softener from your Covina water report

Multiply your hardness in grains per gallon by your household's daily water use and by the days between regenerations, then round up to the next size the maker offers.

Nelsen Corporation, a water treatment supplier, publishes a simple sizing method. It assumes about 75 gallons per person per day. You first add 4 grains for every ppm of iron to get "compensated hardness," then multiply compensated hardness by daily use and by the number of days between regenerations, which it says is typically 3 to 5 days. Covina's City report does not list iron among its averages, so we use hardness alone unless your supplier reports iron.

Find your supplier on the water bill
City of Covina, Suburban, Golden State, Valencia Heights, Azusa Light & Water or Glendora.
Open that supplier's latest water quality report
Find hardness as CaCO3. Note the average and the top of the range.
Convert to grains per gallon
Divide mg/L by 17.1. City water: 230 divided by 17.1 is about 13.5; the 280 high is about 16.4.
Estimate daily use
People in the home times 75 gallons, or use your own bill if you know your usage.
Multiply by days between regenerations
We use 4 days in the examples below, the middle of Nelsen's 3 to 5 day guide.
Round up and check the efficient rating
Nelsen notes that efficient (lower salt) regeneration yields fewer grains than a full salt charge, so compare the grain rating at the salt setting you will actually use.

Worked softener sizing examples, 75 gallons per person per day, 4 days between regenerations (our math using Nelsen's method)
People in the home	Daily use	City of Covina, 13.5 gpg	City high month, 16.4 gpg	Golden State San Dimas, 12 gpg
2	150 gallons	About 8,100 grains	About 9,840 grains	About 7,200 grains
3	225 gallons	About 12,150 grains	About 14,760 grains	About 10,800 grains
4	300 gallons	About 16,200 grains	About 19,680 grains	About 14,400 grains
5	375 gallons	About 20,250 grains	About 24,600 grains	About 18,000 grains
6	450 gallons	About 24,300 grains	About 29,520 grains	About 21,600 grains

These are the grains a unit must remove between regenerations, not a model number. Round up to the next tank size and check its rating at your salt setting. Golden State's own range runs up to about 18 grains, so a San Dimas system customer who wants margin would size closer to the City high month column. An oversized unit is not free either: it costs more up front, and some regenerate on a schedule whether you used the water or not.

Sodium in softened Covina water

Softening City water would roughly double its sodium: the City reports 89 mg/L already, and removing about 13.5 grains of hardness adds roughly another 106 to 108 mg/L.

Two public health sources give the same rule in different units. NDSU Extension says that for every grain of hardness removed, about 8 mg/L of sodium is added. The Vermont Department of Health says about 0.46 mg of sodium is added for each mg of hardness removed. Applied to City water at 230 mg/L, both land near 106 to 108 mg/L of added sodium, for an estimated total of roughly 195 to 200 mg/L at the tap after softening. That is our arithmetic from their rules, not a lab result, and the real number moves with your water's hardness that month.

Vermont notes that the EPA recommends no more than 20 mg/L of sodium in drinking water for people restricted to 500 mg of sodium a day. City water at 89 mg/L is already above that level before softening. If anyone in your home is on a low-sodium diet, the Vermont Department of Health suggests asking your health care provider about the sodium in your water.

Leave the kitchen cold tap unsoftened. Both NDSU and Vermont suggest bypassing the softener for the drinking and cooking tap. We plumb this when we install.
Leave outdoor hose bibs unsoftened. NDSU says softened water is not recommended for watering plants, lawns and gardens because of its sodium content.
Consider potassium chloride. NDSU says it can replace sodium chloride when sodium must be limited, but it costs more and uses about 10% more salt during backflushing. Vermont says it is less effective at removing hardness.
Add RO at the kitchen sink. An under-sink reverse osmosis unit after the softener is another way to get low-sodium drinking water.

Installing a softener in an older Covina home

A softener goes on the main water line after it enters the house and before the water heater, with a bypass valve, a drain for the brine and, for most units, an electrical outlet.

About two-thirds of Covina homes were built before 1970, according to the City's 2024 Housing Element. In many of them, the main line comes up near the front hose bib or the garage, and the water heater sits in the garage. That is often the easiest place to put a softener. We look at four things on the first visit:

Where the main enters and whether the outdoor hose bibs and irrigation can stay on hard water ahead of the softener.
A drain for the brine. The softener's backflush needs an approved drain connection with an air gap.
Power. Most metered and timed control valves need an outlet nearby.
The pipe itself. If the house still has original galvanized supply pipe, softened water will not fix the scale and rust already inside it. Our repiping page covers when that pipe should go.

The City of Covina's Handout #14 says plumbing work requires a permit and that no work may be concealed before inspection. Building & Safety is at 125 E College St and issues most permits over the counter, in person. Ask there whether your specific softener install needs one; we pull permits when they are required. If you live in unincorporated Charter Oak, County rules apply instead of the City's. Our Covina permit guide covers the counter process.

Read the bill and the report
We confirm your supplier and its latest hardness before recommending anything.
Size and choose the unit
Grains from the sizing table, a demand-based control valve, and a salt type that suits the household.
Plan the loop
Bypass valve, unsoftened kitchen cold tap if wanted, hose bibs left on hard water.
Install and set the hardness
We program the valve with your supplier's number, set toward the top of its range.
Test and show you the bypass
We test the softened water and show you how to bypass the unit if it ever leaks.

Are water softeners allowed in Covina?

We have not found any ban on residential softeners that covers Covina, but California law lets some sewer agencies restrict them, so it is worth checking before you buy.

Softener brine is salty, and sewage treatment does not remove salt. California Water Code section 13148 lets a local agency that runs a sewer system or water recycling plant control residential self-regenerating softeners in certain regions, after a regional water board finding and a public hearing. The allowed measures range from requiring high efficiency units and plumbing permits to banning new installations and requiring removal, with compensation offered for removed units. The law does not limit portable exchange tank services.

In Los Angeles County, the Sanitation Districts' softener page covers the Santa Clarita Valley, where automatic softener installation has been prohibited since its 2003 ordinance and a 2008 measure required residential units to be removed. That page speaks only to the Santa Clarita Valley. If you are buying a high-end unit, a quick call to City Building & Safety at 626-384-5460 is cheap insurance.

Hard water, water heaters and tankless units

Hard water is hardest on water heaters, because heat drives calcium out of the water and onto the tank bottom or the tankless heat exchanger.

In a tank heater, scale settles as sediment and you hear it as popping or rumbling. In a tankless unit, it coats the heat exchanger and shows up as error codes and lower flow. At Covina's hardness, regular flushing or descaling is the minimum, softener or not. A softener reduces how often you need to do it. It does not remove scale already built up, so we usually flush or descale the heater at the same visit we install a softener.

Our water heater repair page covers tank heaters and the City's Handout #12 rules for replacements, and our tankless water heater page covers descaling. For scale on faucets, toilets and showerheads, see our toilet and faucet repair page.

Water softener cost ranges

Inch Calculator publishes $500 to $6,000 for a whole-house softener fully installed; that is a published estimate, not a quote. Call (626) 746-1970 for an exact quote.

Published water softener cost ranges (Inch Calculator, last updated September 2023; national estimates, not our prices)
Item	Published range
Whole-house softener, fully installed	$500 to $6,000
Ion exchange (salt-based) system, one or two tanks	$400 to $1,200
Dual tank system	$1,000 to $2,200
40-pound bag of softener salt	$5 to $10

These are national figures from 2023, and they are wide for a reason: the unit, its grain size, the control valve, the loop and any permit all move the price. In older Covina homes, rerouting the main or adding a drain connection can push a job toward the top of a range. You get a written price before work starts. Call (626) 746-1970 for an exact quote. Our plumbing costs guide has ranges for related work.

Ongoing costs to plan for

Salt or potassium chloride, refilled as the brine tank drops.
Water and power for each regeneration.
Occasional resin and valve service over the life of the unit.
Pre-filters or RO cartridges, if you add them.

Call (626) 746-1970 Request service

Softener upkeep in Covina

Keep salt in the brine tank, check the hardness setting when your supplier publishes a new report, and test the softened water now and then.

Each month: look in the brine tank. Keep it above the water line and break up any salt crust.
Each year: when your supplier publishes its new water quality report, check the hardness. If your supplier's hardness changed, update the setting on the valve.
After a power outage: check that the clock or controller kept its settings.
If you see spots again: test the water. An empty brine tank, a stuck valve or a bypass left open are the usual causes.
If it leaks: turn the bypass valve and call (626) 746-1970. Phones are answered 24/7.

Work is done by independent CSLB-licensed C-36 plumbing contractors. Our license check guide shows how to verify one.

Questions Covina homeowners ask

Is Covina water hard?

Yes, very hard. The City of Covina's 2025 water report lists an average hardness of 230 mg/L, about 13.5 grains per gallon, with a range of 190 to 280 mg/L. Golden State Water's San Dimas system reported about 205 mg/L. Your supplier depends on your address.

Do I need a water softener in Covina?

No, it is optional. City water meets state and federal standards, and hard water is not considered a health risk. A softener reduces scale, spotting and wear on fixtures and water heaters. Whether that is worth the cost and upkeep depends on your home.

How do I know which water company I have in Covina?

Look at the name on your water bill. Six suppliers serve parts of Covina: City of Covina Water, Suburban Water Systems, Golden State Water, Valencia Heights Water Company, Azusa Light & Water and Glendora Water. Each publishes its own water quality report with a hardness figure.

What size water softener do I need?

Multiply your hardness in grains per gallon by daily use and by the days between regenerations. A family of four on City water at 13.5 grains, using 75 gallons each per day and regenerating every 4 days, needs about 16,200 grains. Round up to the next size.

Does a water softener add sodium?

Yes. NDSU Extension says about 8 mg/L of sodium is added for each grain of hardness removed. Covina City water already has 89 mg/L of sodium, so softening could take it to roughly 195 to 200 mg/L. Many people leave the kitchen cold tap unsoftened.

Will a water filter soften my water?

No. Carbon and sediment filters are sold for taste, odor, chlorine and grit, not hardness. Check any product's certification for what it reduces. Reverse osmosis treats drinking water at one tap, and hard water can scale its membrane, so softening ahead of it helps.

Do salt-free water softeners work?

They do not soften. Salt-free units such as TAC leave the calcium and magnesium in the water and aim to keep it from forming hard scale. Soap and spotting behave like hard water. Much of the published testing is sponsored by the companies that sell them.

Are water softeners banned in Covina?

We have not found a ban covering Covina. California law lets some sewer agencies restrict softeners that discharge brine, and Los Angeles County Sanitation Districts prohibited them in the Santa Clarita Valley. Ask City Building & Safety before buying if you want to be sure.

How much does a water softener cost in Covina?

Inch Calculator publishes $500 to $6,000 for a whole-house softener fully installed, a national estimate last updated in 2023. Unit size, the plumbing loop and any permit affect the price. That is a published range, not a quote. Call (626) 746-1970 for an exact quote.

Related Covina plumbing help

Covina neighborhoods we serve

Sources

Facts on this page come from these public sources, checked November 1, 2026.