Where Des Moines-Area Water Comes From: A Town-by-Town Guide

Key facts: Des Moines-area water

• Regional supplier: Central Iowa Water Works (CIWW), set up April 11, 2024, by 12 founding members that serve more than 600,000 people (CIWW, checked Oct 2026)
• River plants: Fleur Drive (up to 75 million gallons a day), L.D. McMullen (25) and Saylorville (10), all run by Des Moines Water Works (CIWW; DMWW 2026 report)
• River-plant hardness: 8.5 to 8.9 gpg (145 to 152 mg/L), 2025 averages of treated water leaving the three plants (DMWW plant data, 2025)
• Town figures: highest, Ames at 9.4 gpg (161 mg/L), September 2026 monthly average (City of Ames); lowest, Grimes at 5.8 gpg (100 mg/L) in one 2022 sample (Iowa DNR) and Indianola at 5.8 to 7 gpg, undated (Indianola Municipal Utilities)
• No number published: Altoona, Adel and Polk City (latest water reports and Iowa DNR records, checked Oct 2026). We measure yours at the sink.
• Chloramine, not chlorine: Ames, Grimes and Warren Water District (EPA records)
• Raw well water: 20.5 to 29.8 gpg (350 to 510 mg/L) in raw samples from city wells in Adel, Grimes, Bondurant, Altoona and Ames, 2019 to 2026, before treatment (Iowa DNR; City of Ames)
• EWG's lists: 2 to 15 chemicals above EWG's own guidelines per utility in our table (EWG Tap Water Database, 2021–2023 data; radiological 2018–2023 where listed)
• Screening: Free home screening measures hardness, iron, TDS and a nitrate screening reading. It also checks chlorine.
• Prices: Softener + whole-home carbon $2,500 · softener only $1,900 · add a tank or tankless kitchen RO: $2,850 · installed, tax included (Kind Water Co price book, Oct 2026)
• Office: Kind Water Co · 600 SE 15th St, Des Moines, IA 50317 · call or text 515-709-4674

What is Central Iowa Water Works?

Central Iowa Water Works, or CIWW, is the regional water authority for most of the Des Moines metro. It was set up on April 11, 2024. It is in charge of water treatment, system planning and wholesale delivery across the metro (CIWW).

Its 12 founding members are Des Moines Water Works, West Des Moines Water Works, Urbandale Water Utility, Warren Water District, Xenia Rural Water and the cities of Ankeny, Clive, Grimes, Johnston, Norwalk, Polk City and Waukee. Together they serve more than 600,000 people (CIWW FAQ).

EPA records moved the three river plants into CIWW's system on January 1, 2025. Des Moines Water Works still runs them. Your city or water district still answers questions about your service (CIWW).

The three river plants

Most metro tap water starts in the Raccoon and Des Moines rivers. Three plants run by Des Moines Water Works turn it into drinking water (DMWW 2026 report; CIWW).

• Fleur Drive is the biggest, at up to 75 million gallons a day. It draws from both rivers and an infiltration gallery in Water Works Park, and it softens with lime. It serves every area the other two plants don't.
• L.D. McMullen, at Maffitt Reservoir southwest of the metro, makes up to 25 million gallons a day from collector wells along the Raccoon River. It softens with lime. It serves southern Des Moines, Waukee and parts of Clive, Urbandale, West Des Moines and Warren Water District.
• Saylorville, in northern Polk County, makes up to 10 million gallons a day from collector wells along the Des Moines River. It softens and cleans the water with ultrafiltration and reverse osmosis. It serves homes north of Des Moines.

All three plants disinfect with chlorine (EPA). Their treated water averaged 8.5 to 8.9 grains in 2025. The U.S. Geological Survey still calls that "hard," a band that runs from 121 to 180 mg/L.

Town by town: who supplies your water

Find your town below. Each town name opens our page for that town. "Not published" means we found no current tap hardness number for that town in its water report, on its city water page or in Iowa DNR sample records (checked October 2026). Where a town buys plant water, we show the plant figure instead.

How to read the table:

• Hardness is treated water, shown as an average or range for the period listed. 1 grain per gallon (gpg) equals 17.1 mg/L, and ppm means the same as mg/L.
• Disinfectant levels are yearly averages in each town's pipes, from its water report, unless a plant is named.
• The EWG column counts the chemicals EWG lists above its own health guidelines for that utility, using 2021–2023 data. † means EWG's page also lists radiological results from 2018 to 2023.

Nine more towns near Des Moines

We're still checking these towns' current supply and hardness. For now, this table shows each utility and EWG's count only.

Towns that use local wells

Altoona pumps from three city wells about 2,500 feet deep in the Jordan aquifer, drilled in 1968, 1976 and 1998 (Iowa DNR). All three of its plants soften by ion exchange (EPA). Its 2025 water report has no hardness row, and it lists sodium of 124 to 145 ppm leaving the plants.

Indianola Municipal Utilities lime-softens water from four Jordan wells about 2,600 feet deep, to 5.8 to 7 grains by its own count. Many rural homes nearby are on Warren Water District instead (CIWW).

Adel pumps seven shallow wells, 40 to 59 feet deep, in alluvial sand and gravel (Iowa DNR). Its reverse osmosis softening plant was fully online in March 2021 (City of Adel). Raw water from its newer wells tested 20.5 to 25.7 grains in 2019 and 2024 samples (Iowa DNR). No number is published for the water it delivers.

Ames draws from more than 20 wells in old riverbed sand and gravel along Ioway Creek and the South Skunk River. In September 2026, lime softening took its water from 437 mg/L raw to 161 mg/L treated, still hard on the USGS scale. Ames disinfects with chloramine (City of Ames; EPA). More on reverse osmosis for Ames homes.

Grimes buys finished water from CIWW, which has owned the city's wells and plants since 2025 (EPA). A lime plant from 2001 and an RO plant from 2021 treat water from shallow and deep wells, and the two outputs are blended (City of Grimes; CIWW).

Polk City water is "a blend of local groundwater and regional supply," the city says. The local plant filters out iron but does not soften (EPA). The 2024 water report lists manganese at 0.078 mg/L on average, with a high of 0.39 mg/L.

West Des Moines Water Works softens water from 17 shallow Raccoon River wells and 4 Jordan wells at its A.C. Ward plant, and it buys CIWW river water too. About 25% of customers, in the northwest and southeast, get only river water; the 2025 report has a map. A.C. Ward's sodium was 210 ppm in 2024 (WDMWW). More on reverse osmosis for West Des Moines homes.

Where the water is changing

• Urbandale closed its old Des Moines Water Works connection on March 28, 2025, and now buys from CIWW. The utility treats nothing itself (EPA; Urbandale Water Utility).
• Bondurant buys all of its water from Des Moines Water Works today and has no city water storage (Iowa SRF notice, July 2025). That notice plans new city wells and a plant. Raw samples from new Wells 6 and 7 read 24.0 to 24.6 grains (410 to 420 mg/L) in 2026, before any treatment (Iowa DNR).

How hard is the water in each town?

Treated water, hardest first:

• Ames: 9.4 gpg (161 mg/L), September 2026 monthly average. USGS class: hard.
• CIWW river plants: 8.5 to 8.9 gpg (145 to 152 mg/L), 2025 averages, for Des Moines, Windsor Heights, Pleasant Hill, Ankeny, Johnston, Urbandale, Clive, Norwalk, Bondurant and the river-water parts of West Des Moines. USGS class: hard.
• Waukee: 7.5 to 8.5 gpg, the city's published average (undated). USGS class: hard.
• Indianola: 5.8 to 7 gpg (100 to 120 mg/L), utility range. USGS class: moderately hard.
• Grimes: 5.8 gpg (100 mg/L), one 2022 sample. USGS class: moderately hard.
• Altoona, Adel and Polk City: no number published, so we measure yours at the sink.

Softened at the plant is not the same as soft at the tap. Groundwater before treatment is much harder: raw city-well samples around the metro read 20.5 to 29.8 grains from 2019 to 2026. Compare more cities on our Iowa water hardness by city table.

What EWG's Tap Water Database shows

The Environmental Working Group (EWG) posts utility test results in its online Tap Water Database. Our counts come from EWG's page for each utility, using its 2021–2023 data, plus radiological results from 2018 to 2023 where EWG lists them.

• EWG compares each result with its own health guideline. Those guidelines are EWG's own goals, not legal limits.
• In most towns, 8 to 10 of EWG's flags are byproducts of disinfection, such as total trihalomethanes (DMWW and WDMWW reports).
• Ames and Grimes, both groundwater systems, have the shortest lists: 6 and 2.
• The counts don't line up exactly from town to town. Some EWG pages include radiological results and some don't, and the data is from before CIWW took over the river plants.

We share these counts as facts, not as a verdict on any town's water. We don't claim our systems remove the chemicals on EWG's lists.

Rural water and private wells

Outside city limits, many homes get piped water from a rural water district. Three serve the metro's edges:

• Southeast Polk Rural Water District (IA7774701) serves about 7,565 people, including Runnells and eastern Pleasant Hill. It buys from Des Moines Water Works (EPA; DMWW 2026 report).
• Warren Water District (IA9133701), based in Indianola, serves about 20,095 people across rural Warren, Madison, southern Dallas and part of Polk counties. It buys CIWW river water and adds chlorine and ammonia at a booster, which makes chloramine (EPA; CIWW).
• Xenia Rural Water District serves all or part of 11 counties, 16 communities and more than 10,500 customers (CIWW).

On a private well, testing is up to you, and it's free. Iowa's Private Well Grants program pays for yearly county testing (Iowa DNR). Call your county:

Raw samples from city wells around the metro tested 20.5 to 29.8 grains, so a private well nearby is likely to be hard too. Your own test tells you for sure.

How to find out which water reaches your house

1. Check who sends your water bill. In Windsor Heights and most of Pleasant Hill, it's Des Moines Water Works. On Pleasant Hill's east side, it may be Southeast Polk Rural Water.
2. Open that utility's yearly water report. It names the plant or wells behind your water. We link every report in Sources below.
3. Let us test it. Our free in-home test reads your hardness at the sink. That matters most in towns that blend two supplies or post no number.

What your town's water means for treatment

• Plant-softened water is still hard. Hard water can cause scale in pipes, appliances and fixtures, West Des Moines Water Works' report notes. Our softener with whole-home carbon is $2,500 installed, tax included. Softener only is $1,900, but it has no carbon, so it does not remove chlorine or chloramine. Add a 7-stage kitchen reverse osmosis system, tank or tankless, your choice, and the whole system is $2,850.
• Chlorine towns, which is most of the metro, get the regular carbon already in that $2,500 system.
• Chloramine towns (Ames, Grimes and Warren Water District homes) get catalytic carbon. It adds $150 to our standard system, making it $3,000 with kitchen RO. A carbon-only tank is $1,150 regular or $1,450 catalytic. See chlorine and chloramine filters for Des Moines-area homes.
• Towns with more sodium: Altoona (124 to 145 ppm, 2025), West Des Moines' A.C. Ward plant (210 ppm, 2024) and Indianola (160 ppm, 2025) report more sodium than the river plants, whose highest 2025 reading was 53.4 mg/L. Sodium is one part of TDS, the dissolved minerals and salts our RO is certified to reduce. A kitchen reverse osmosis system is $897 with a tank or $997 tankless. Both are 7-stage and certified to NSF/ANSI 58 for TDS reduction. RO filter care is $199 a year if we mail you the filters and you swap them, or $249 a year if we come out, swap them and test your water. Compare reverse osmosis options in Des Moines.
• Private wells: our dual-tank well system is $3,650, or $3,950 with a tank RO. That is a starting price; a long trench, distance or rock can raise it. On a well we install tank RO only.

Every system is installed by licensed local plumbing professionals we vet, schedule, and stand behind. For the full price list, see our Des Moines water softener cost guide.

Your free in-home water test

Not sure which row is yours? We'll measure your hardness at the sink for free and tell you where your water comes from. Kind Water Co is based at 600 SE 15th St in Des Moines. Call or text 515-709-4674, or book your free water test. See what we install on our water softeners in Des Moines page.

Live in Eastern Iowa? See where Eastern Iowa's water comes from.