Dakota County, Minnesota: well water test test at sale
Checked on November 9, 2026 against the official rule. Rule set by Dakota County.
General information, not legal advice. This is our summary of the official rule as we read it. The ordinance or code and the health department decide: confirm with them before you list, sign or close.
The rule
Any well used for drinking water at the time of transfer. State law also requires a Well Disclosure Certificate (Minn. Stat. 103I.235).
| Question | What the official text says |
|---|---|
| What is required | A water analysis by a laboratory certified by the Minnesota Department of Health within one year before the sale, for coliform bacteria, nitrate, manganese and arsenic Source: dakotacountymn.gov |
| Triggered by | sale, transfer Source: dakotacountymn.gov |
| Deadline | Water analysis within 1 year prior to property sale Source: dakotacountymn.gov |
| How long a report is valid | Water test within one year before the sale Source: dakotacountymn.gov |
| Well part | County page: water analysis by MDH-certified lab 'within one year prior to a property sale'; parameters coliform bacteria, nitrate, manganese, arsenic. Source: dakotacountymn.gov |
This is our summary of the official rule as we read it. The ordinance or code and the health department decide: confirm with them before you list, sign or close. Rule set by: Dakota County.
Checked on November 9, 2026: read on the official site.
Compared with other Minnesota rules
- The only one of the 59 Minnesota local rules that reaches the well; the others cover the septic system only.
Our census of official rules, checked November 9, 2026; start dates as the official text states them.
Private wells in Dakota County
In 2015 about 15,276 of Dakota County’s 414,686 residents (4%) got their drinking water from a private well, by the USGS estimate. That is the 84th highest share of the 87 Minnesota counties in the USGS table, and the 28th highest number of private-well users.
This rule requires a well water test at sale, so it reaches these households directly. USGS models about 219 private-well users in Dakota County with arsenic above 10 µg/L, EPA’s limit for public water (2010 population base; 95% range 176 to 275), the 67th highest of 87 Minnesota counties. It is a screening estimate, not a result for any one well.
Source: USGS county water use 2015 (Dieter et al., 2018); USGS domestic-well arsenic estimate (Ayotte, Medalie and Qi, 2017). Ranks count the Minnesota counties in the USGS table (1 = highest).
Soils and septic systems here
USDA soil surveys rate 88% of Dakota County’s rated land “very limited” for a conventional septic drain field, 12% “somewhat limited” and 0% “not limited”, the 76th highest “very limited” share of 85 Minnesota counties with survey data. The most common limits: slow percolation (dense or clay soil) on 68%; fast seepage below the field (risk to groundwater) on 60%; a high water table (saturated soil near the surface) on 28%.
Where soils are limited, inspections more often find drain fields that sit in seasonally wet soil, and replacement systems are often mounds or other engineered designs. A county-wide rating, not a test of one lot: a site evaluation decides. Source: USDA NRCS Soil Survey Geographic Database (SSURGO), via Soil Data Access, rating “ENG - Septic Tank Absorption Fields”, read November 15, 2026.
Certified labs nearest to Dakota County for a well water test
Labs on the Minnesota certified drinking-water list that the list marks as taking samples from homeowners or outside clients, certified for coliform bacteria, nearest first. 1 of them is in Dakota County.
| Lab | Town | Distance | Certified on the list for |
|---|---|---|---|
| RMB Environmental Laboratories, Inc. - Burnsville | Burnsville, MN · in this county | 8 miles | coliform bacteria, nitrate, arsenic (subcontracted) |
| Pace Analytical Services, LLC - Minneapolis | Minneapolis, MN | 16 miles | coliform bacteria, nitrate, arsenic |
| Twin City Water Clinic, Inc. | Hopkins, MN | 18 miles | coliform bacteria, nitrate, arsenic |
Source: MDH Accredited Labs in Minnesota Accepting Drinking Water Samples from Private Well Users (October 2026; read November 15, 2026). Straight-line distance from the centre of Dakota County (the average of its Census ZIP-area points); “approx.” = lab placed at its ZIP centre. Call the lab first: lists do not say which household tests each lab takes or what it charges.
Nearest other sale-time rules
Buying or selling near a county line? These are the closest other local rules in our census to Dakota County.
| Rule | State | Distance | Covers | Checked |
|---|---|---|---|---|
| Dakota County | Minnesota | same county | Septic system | November 9, 2026 |
| Washington County | Minnesota | about 19 miles | Septic system | November 9, 2026 |
| Rice County | Minnesota | about 29 miles | Septic system | November 9, 2026 |
| Goodhue County | Minnesota | about 32 miles | Septic system | November 9, 2026 |
| Carver County | Minnesota | about 34 miles | Septic system | November 9, 2026 |
Straight-line distance between county centres (the average of each county’s Census ZIP-area points). Townships, villages and health districts are placed at the centre of their county.