Cahaba Water Co. Birmingham, AL
(205) 825-8810 Get a quote
Residential water treatment · Greater Birmingham

Better drinking water. $995 installed.

Four-stage reverse osmosis under your kitchen sink, professionally installed by a licensed Alabama plumbing contractor.

Published pricing. No long in-home sales appointment.

Book the $995 install Compare drinking-water systems

Equipment and standard installation included. Any unusual site-specific work is confirmed before scheduling.

Installed by
A licensed Alabama plumbing contractor
Workmanship
12-month warranty on every install
Components
Pentair Fleck & Clack, any plumber can service
Quoting
From your address and two photos
Where to start

One tap, or every tap.

Two clear starting points. Pick the one that matches what you want changed.

Drinking water Better water at the kitchen tap. Under-sink reverse osmosis for drinking, cooking, coffee and ice. From $995 installed. See drinking-water systems Whole home Treat the water at every tap. Whole-home filtration, conditioning where appropriate, and premium treatment options sized to your home's actual water demand. Sized first. Firm quote second. Start a whole-home assessment
Drinking water

Four under-sink systems. One published price each.

All four are reverse osmosis at your kitchen sink, installed for the price shown.

What changes between them is daily output, the hardware fitted, and the certification wording each platform carries. Nominal GPD means gallons per day at the maker's own test conditions.

ESSENTIAL

Cahaba Pure 50 Drinking water

$995 installed · equipment, labor, warranty
Cahaba Pure 50

Certified protection. Best value.

Reverse osmosis at one tap: drinking, cooking, coffee and ice.

For: homeowners who mainly want better drinking water, with normal household demand and enough pressure feeding the unit.

  • Approximately 4-gallon metal storage tank
  • Standard chrome air-gap faucet
  • Quick-change cartridges
50 GPD nominal4 stages
Point of useFits under the sink

IAPMO R&T certifies this configuration to NSF/ANSI 58 and CSA B483.1, including PFOA and PFOS reduction.

PERFORMANCE

Cahaba Performance 75 Drinking water

$1,095 installed · equipment, labor, warranty
Cahaba Performance 75

More output + pressure support.

Makes more water per day, with a booster pump that supports the pressure feeding the unit.

For: homes that want more water per day, and homes where the feed pressure needs help.

  • NSF-certified 3.0-gallon tank
  • Booster pump fitted, which raises the pressure feeding the unit
75 GPD nominal5 stages
Point of useBooster pump

The manufacturer identifies the membrane and the storage tank as NSF certified, not the complete system.

SIGNATURE

Cahaba Signature 75 Drinking water

$1,295 installed · equipment, labor, warranty
Cahaba Signature 75

High-efficiency traditional RO.

Our premium traditional-tank platform, with a booster pump fitted.

For: homeowners who want the top traditional RO platform Cahaba offers.

  • NSF-certified 3.0-gallon tank
  • Booster pump fitted
  • Stage count not documented
75 GPD nominal
Point of useBooster pump

The storage tank is identified as NSF certified, not the complete system.

TANKLESS

Cahaba Slim 800 Drinking water

$1,295 installed · equipment, labor, warranty
Cahaba Slim 800

High flow. No tank. More cabinet space.

Direct-flow reverse osmosis with no storage vessel, so the cabinet under your sink stays open.

For: choose Slim 800 for cabinet space and direct-flow performance.

  • Tankless, no storage vessel
  • Stage count and booster pump not documented
800 GPD nominal
Point of useDirect flow

A premium alternative at the same installed price as Cahaba Signature 75. Cabinet space and on-demand production are what the choice turns on.

How to choose. Match daily output to how much water your household draws, the hardware to the pressure feeding the unit, and the shape of the system to your cabinet. Each system's certification wording is printed beside the system it belongs to, because every platform carries its own. Compare all four side by side.

Why Cahaba

Premium equipment. Published prices. Licensed installation.

Residential water treatment run like the rest of your home's infrastructure.

01

The price is on the page

Every drinking-water system carries one installed price, published here. Whole-home systems are sized to your house first and quoted in writing before anything is scheduled.

02

Licensed installation

A licensed Alabama plumbing contractor installs, tests and commissions the system, and pulls any permit your municipality requires. Workmanship is warrantied 12 months.

03

Components any plumber can service

Pentair Fleck and Clack control platforms, Structural vessels, Jacobi carbon, ResinTech resin. These sit on the shelf at supply houses across Birmingham, so your system stays serviceable by whoever you choose.

04

Claims you can check

Each system's certification wording is published beside that system, and we'll give you the certifier's listing number for anything we supply. See the certification register.

Pentair / FleckStructuralJacobiResinTech VIQUAGrundfos
Whole home

Treat the water at every tap.

Three treatment levels, each built around what your water actually shows.

Essential

Cahaba Whole Home Essential

Carbon filtration on your main line, so every tap in the house gets it.

Sized first. Firm quote second.
Complete Our main system

Cahaba Whole Home Complete

Carbon filtration, softening where your hardness result calls for it, and a Cahaba under-sink RO included.

Sized first. Firm quote second.
Signature

Cahaba Whole Home Signature

Our most complete build, designed around your house, carrying the widest set of options.

Sized first. Firm quote second.

Available in S / M / L / XL based on actual flow requirements.

Start a whole-home assessment See what each level includes

Options, where the house calls for them

Decision

Drinking water, alongside

Cahaba Whole Home Complete includes a Cahaba under-sink RO. With Cahaba Whole Home Essential you can add one at its published price, now or later.

An RO treats one fixture. A whole-home system treats every tap. Plenty of homes correctly make just one of the two decisions.

Size

XL, Estate Flow

The largest of the four sizes, specified when a house's measured peak flow calls for it. That can mean twin-tank softening where capacity has to be continuous, with UV matched to the same flow.

Chosen on flow and pressure. We measure first, then specify. Estate work.

Option

Pressure Assurance

A variable-speed pump that raises household water pressure. We specify it after measuring pressure standing still, pressure under real demand, and your peak flow.

Treatment is sized for your flow first. Then we decide whether boosting adds anything.

Option

Water Resilience & Storage

A tank that stores city drinking water at your house. A pump returns it to pressure, and it gets treatment and UV, so the house keeps running through an outage or a boil-water notice.

Think of it the way you think of a standby generator or a home battery. How storage builds work.

Every component is made by a company you can look up, and each system carries its own certification statement. Components, maker by maker · the certification register · treatment level and size.

How it works

Three steps to better water.

Carbon capacity follows your peak flow. Softening follows your measured hardness. Boosting follows a pressure test.

STEP 01

Choose your starting point

An under-sink RO at its published price, or a whole-home assessment. Tell us your address and we look up which plant serves you and what your water contains.

STEP 02

We confirm the details

Send two photos: under your kitchen sink, and your water heater area. For a whole-home system we also measure pressure and flow and size the equipment to it. You get a firm number in writing before anything is scheduled.

STEP 03

Licensed installation

A licensed Alabama plumbing contractor installs the system, tests it and starts it up, pulls any permit required, then walks you through it. Most jobs are a single visit.

Not sure which one you need?

Send your number. We'll mail a free hardness test and size the recommendation around what your water actually shows.

The Cahaba River winding through hardwood forest in morning mist, with pale limestone shoals visible beneath clear shallow water.
One of our source waters The Cahaba is one of several source waters for this system, alongside the Little Cahaba, Lake Purdy, Inland Lake and the Black Warrior. Surface water is also why taste changes with the seasons. It gives our company its name.
Birmingham water

Birmingham's water is safe. We work on how it tastes.

In May 2024, homes in Homewood, Vestavia Hills, Mountain Brook and North Hoover all reported the same thing: water that tasted musty and earthy. Central Alabama Water (formerly Birmingham Water Works) identified geosmin, a harmless compound algae make in the lakes and rivers this city draws from. It is seasonal, so it returns each spring. The full picture of what this system publishes.

Birmingham water meets every federal and state standard. It is chlorinated, it carries disinfection byproducts within legal limits, and it contains detectable PFOA and PFOS below the EPA limit, all of it published annually. A whole-home carbon filter reduces the musty taste, and at full household flow it does so partially. The under-sink reverse osmosis system is what reliably fixes it at the tap you drink from, which is why the $995 system is the one most people start with.

Clear water running from a brushed-nickel kitchen faucet into a stainless steel sink in a bright kitchen.
Clear, compliant, and sometimes musty in spring
Hardness, measured

A water softener isn't automatic in Birmingham.

Hardness varies by source and by location, so we test before recommending one.

If the number is low we'll tell you. If your hardness and your goals justify softening, we size it accordingly. Hardness is measured in grains per gallon, and Central Alabama Water publishes the system's numbers every year, and here is where they fall.

Total hardness · grains per gallon
Central Alabama Water 2026 Annual Water Quality Report (2025 data)
Central Alabama Water only. Pelham, Alabaster and Trussville run harder, see your utility.
Soft Slightly Moderate Hard Very hard 2.2 13.1 Central Alabama Water, measured range 15 25 Phoenix · Las Vegas · San Antonio where softeners are standard equipment 0510 152025
Central Alabama Water, measured range
2.213.1
Phoenix · Las Vegas · San Antonio
1525

where softeners are standard equipment

0510 152025
Soft Mod. Hard Very hard

Say your result comes back at the low end of that range. Then we'll tell you a softener has little work to do in your house, and point you at the $995 drinking-water system instead. The right thing beats the expensive thing.

A water hardness test strip showing a green-to-teal gradient pad, beside a clear glass of water and a plain paper envelope.
Free hardness test, mailed rather than sold

Sizing follows what we measure, not a package name. See how we size a system.

A quiet tree-lined residential street of traditional brick and clapboard homes in autumn light.
Service area Birmingham, Hoover, Pelham, Alabaster, Trussville, Bessemer, Gardendale and Shelby County
What's included

$995 including standard installation.

Equipment, labor and the 12-month workmanship warranty, fitted by a licensed Alabama plumbing contractor.

“Standard installation” is defined here rather than implied, so you know what the price covers before you buy. Here is exactly what our prices assume.

What “standard installation” assumes about your home
Whole-home systems assume
  • An accessible main water line in a garage, basement or utility space
  • An existing softener loop, or an accessible main we can tie into
  • A drain within 10 feet. Filters flush water out when they clean themselves
  • A grounded outlet within 6 feet
  • Copper, PEX or CPVC pipe in serviceable condition
  • Static water pressure between 40 and 80 psi
The under-sink RO assumes
  • An accessible cold-water stop beneath the sink
  • An existing faucet hole, or a countertop we can drill
  • A standard trap we can fit a drain saddle to
  • Room in the cabinet for the unit and its tank
Every system assumes
  • A single-family home on municipal water
  • Within our service area

If your home needs something beyond that list, we price it from the schedule below and from photos you send, and confirm it in writing before we schedule. The number you approve is the number you pay, subject only to unusual site conditions confirmed before scheduling.

What could change your price

ConditionWhat's involvedAdded
No softener loopCut into the main line and build a bypass. Common in older Birmingham homes.+$275
No nearby drainRun a drain line with proper air gap beyond 10 feet.+$150
No nearby outletCoordinate an electrician for a receptacle within reach of the valve.+$180
Crawlspace routingRun supply and drain through a crawlspace rather than a garage wall.+$225
PermitWhere your municipality requires one, passed through at cost.at cost
Warranty callbackAnything that's our workmanship, for 12 months.$0
Questions we actually get

The honest answers.

Is Birmingham's water unsafe?
No. Central Alabama Water meets every federal and state drinking water standard, and publishes its results annually. What we improve is taste, odor and chlorine, and, at the drinking tap, the contaminants the RO is certified for.
Do I need a water softener?
Sometimes. Central Alabama Water publishes a system-wide range of 2.2 to 13.1 grains per gallon, slightly hard at one end of the system and very hard at the other. Where your address falls in that span is what decides it, so we test before recommending one. We'll mail you a free test strip and read the number with you. If it comes back low we'll tell you, and point you at the drinking-water system instead. If your hardness and your goals justify softening, we size it accordingly.
What is included in the $995 RO price?
Equipment, standard installation and the 12-month workmanship warranty. Standard installation assumes an accessible cold-water stop beneath the sink, an existing faucet hole or a countertop we can drill, a standard trap we can fit a drain saddle to, and room in the cabinet for the unit and its tank. Anything beyond that is quoted from our published schedule and confirmed in writing before scheduling.
What's the difference between Pure, Performance, Signature and Slim?
Daily output, the hardware fitted, and the certification wording each platform carries. Cahaba Pure 50 is nominal 50 GPD across four stages at $995. IAPMO R&T certifies this configuration to NSF/ANSI 58 and CSA B483.1, including PFOA and PFOS reduction. Cahaba Performance 75 is nominal 75 GPD across five stages at $1,095 and adds a booster pump for homes where the feed pressure needs support. The manufacturer identifies the membrane and the storage tank as NSF certified, not the complete system. Cahaba Signature 75 is our premium traditional-tank platform at $1,295, also with a booster pump. The storage tank is identified as NSF certified, not the complete system. Cahaba Slim 800 is tankless at $1,295. Choose it for cabinet space and direct-flow performance. Each system carries its own certification wording, printed beside it.
How do you determine which whole-home system I need?
By answering two separate questions. The treatment level follows your water and your goals, and gives you Cahaba Whole Home Essential, Complete or Signature. The system size follows your plumbing (service line, fixture count, simultaneous demand and measured pressure) and gives you S Standard Flow, M Enhanced Flow, L High Flow or XL Estate Flow. A six-bath home may need Essential XL. A two-bath home may need Signature S. Bigger does not mean better. Properly sized does. The finished build carries both answers in its name, for example Cahaba Whole Home Complete‑M.
Who installs the system?
A licensed Alabama plumbing contractor, named on your contract with their PGFB registration number. Workmanship is warrantied 12 months. We use standard Pentair Fleck and Clack platforms with parts available at any plumbing supply house, so your system stays serviceable by whoever you choose.

More questions answered: certification, filter changes, sodium, service intervals and sizing.

Get your price

Tell us where you are. We'll send your number.

We quote from your address and a couple of photos, usually the same day. You'll get the system that fits, the installed price, and any site condition that applies, in writing.

  • 01A real person calls you back, usually within the hour
  • 02Free hardness test mailed if you're considering softening
  • 03Firm price before anything is scheduled
  • 04Installed by a licensed Alabama plumbing contractor
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Cahaba Pure 50, $995 installed Published price · standard installation included
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