Skip to content
AquaCensus

Winneshiek County, Iowa — public water systems

At a glance

43 active public water systems are filed under Winneshiek County, Iowa in EPA's SDWIS records, together reporting 14,733 people served. The largest is Decorah Water Department, which reports serving 7,615 people. 13 are community water systems serving people where they live; the other 30 are non-community systems, such as schools, workplaces, campgrounds and gas stations with their own supply.

Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.

Active systems

43

Population served

14.7K

Community systems

13

Groundwater share

100%

How does Winneshiek County compare with other Iowa counties?

Winneshiek County has the 6th-most active public water systems among the 114 counties listed for active Iowa systems in EPA records; among the 96 with 3 or more systems, the median has 14. Its systems report 14,733 people served in total, the 42nd-largest county figure in the state and 0.5% of the statewide total. The average system here reports serving 343 people, well below the Iowa average of 1,718. Population figures are what each system reports; people served by more than one system, such as a wholesaler and the town that buys from it, are counted by each.

Where does Winneshiek County's drinking water come from?

By primary water source, Winneshiek County's active systems draw on groundwater (43, 100%). Overall, all rely mainly on groundwater (including purchased groundwater) and none on surface water, compared with 92% and 7.8% across Iowa. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, Decorah Water Department, draws primarily on groundwater.

What kinds of water systems operate in Winneshiek County?

Winneshiek County's active systems break down as 13 community systems (30%), 3 non-transient non-community systems (7%) and 27 transient non-community systems (63%). A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. EPA lists their owner types as private (63%), local government (30%), public/private partnership (4.7%) and state government (2.3%).

Water systems in Winneshiek County

🔒 Create a free account to export CSV
Active public water systems in Winneshiek County, Iowa
#Water systemCountyPopulation servedTypeSource
1Decorah Water DepartmentWinneshiek7,615CommunityGroundwater
2Calmar Water SupplyWinneshiek1,125CommunityGroundwater
3Ossian Water SupplyWinneshiek802CommunityGroundwater
4Freeport Water DistrictWinneshiek775CommunityGroundwater
5The Country ExpressWinneshiek515Transient non-communityGroundwater
6Turkey Valley Community SchoolWinneshiek490Non-transient non-communityGroundwater
7Spillville Water SupplyWinneshiek371CommunityGroundwater
8Fort Atkinson Water WorksWinneshiek347CommunityGroundwater
9Ridgeway, City ofWinneshiek275CommunityGroundwater
10South Winn Golf ClubWinneshiek218Transient non-communityGroundwater
11Our Lady of Seven Dolors ParishWinneshiek210Transient non-communityGroundwater
12Castalia Water WorksWinneshiek145CommunityGroundwater
13Frankville RwdWinneshiek135CommunityGroundwater
14Harvest Farm Campground LLCWinneshiek129Transient non-communityGroundwater
15Washington Prairie Lutheran ChurchWinneshiek124Transient non-communityGroundwater
16Pulpit Rock Camp GroundsWinneshiek112Transient non-communityGroundwater
17Decorah Sales CommissionWinneshiek105Transient non-communityGroundwater
18Seed Savers ExchangeWinneshiek100Non-transient non-communityGroundwater
19Silvercrest Golf & Country Club, Inc..Winneshiek88Transient non-communityGroundwater
20Scenic View EstatesWinneshiek78CommunityGroundwater
21Sherman Place Water & Road, Inc..Winneshiek73CommunityGroundwater
22Jackson Heights Golf CourseWinneshiek72Transient non-communityGroundwater
23Bluffton ResortWinneshiek60Transient non-communityGroundwater
24Highland General Store & CampgroundWinneshiek59Transient non-communityGroundwater
25Twin Springs Supper Club, L.L.C.Winneshiek52Transient non-communityGroundwater
26Kendallville ParkWinneshiek50Transient non-communityGroundwater
27Decorah Fish HatcheryWinneshiek50Transient non-communityGroundwater
28Bodensteiner Implement CompanyWinneshiek50Transient non-communityGroundwater
29Burr Oak Lutheran ChurchWinneshiek50Transient non-communityGroundwater
30Laura Ingalls Wilder Museum WellWinneshiek46Transient non-communityGroundwater
31Windridge Implements L.L.C.Winneshiek45Transient non-communityGroundwater
32Pine Bluff 4h CampWinneshiek41Transient non-communityGroundwater
33The ZipperWinneshiek35Transient non-communityGroundwater
34Barneys Bar and GrillWinneshiek35Transient non-communityGroundwater
35Under the Stars at Chimney Rock Cg LLCWinneshiek33Transient non-communityGroundwater
36Plantation Country View SubdivisionWinneshiek32CommunityGroundwater
37Twin Springs Camp AreaWinneshiek32Transient non-communityGroundwater
38Henning Commercial SubdivisionWinneshiek31Non-transient non-communityGroundwater
39Deerfield Heights AssociationWinneshiek28CommunityGroundwater
40K-Town TapWinneshiek25Transient non-communityGroundwater
41Big Springs WellWinneshiek25Transient non-communityGroundwater
42Lake Meyer ParkWinneshiek25Transient non-communityGroundwater
43Pinters Garden Center & Pumpkin PatchWinneshiek25Transient non-communityGroundwater

Winneshiek County water systems: frequently asked questions

How many public water systems are in Winneshiek County, Iowa?

EPA's SDWIS records file 43 active public water systems under Winneshiek County, Iowa: 13 community systems (30%), 3 non-transient non-community systems (7%) and 27 transient non-community systems (63%).

Who supplies drinking water in Winneshiek County, IA?

The largest community water systems filed under Winneshiek County are Decorah Water Department (7,615 people served), Calmar Water Supply (1,125 people served) and Ossian Water Supply (802 people served). Which system serves a particular address depends on its service area, which EPA's SDWIS records do not include; a water bill or the local utility can confirm it.

Does Winneshiek County's drinking water come from groundwater or surface water?

Of the 43 active public water systems in Winneshiek County, all draw mainly on groundwater and none on surface water, counting purchased supplies. The largest system, Decorah Water Department, uses groundwater.

Where can I find a water quality report for Winneshiek County?

Each community water system must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1, covering the previous calendar year. 13 community systems are filed under Winneshiek County, so the report to look for is the one from the system that supplies your address.

How can I check violations for a water system in Winneshiek County?

Open the system's profile from the list on this page. Each profile shows the most recent Safe Drinking Water Act violations in EPA's records, with plain-English labels and whether each one is resolved. For current compliance status, EPA ECHO is the primary source.

More Iowa water systems

About this data

Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.

Cite as: AquaCensus, “Public water systems in Winneshiek County, Iowa”, https://aquacensus.com/water-systems/iowa/winneshiek (data as of October 1, 2026).