- Environmental Services
- Septic Systems
Over 8,700 homes in Scott County rely on a septic system for their on-site wastewater treatment. A septic system is a large and important investment. It is vital that homeowners understand how their system works, and that they do what they can to extend the life of their Septic System. The positive benefits of a properly-functioning and long-lasting septic system are both financial and environmental.
Despite our abundance of lakes and rivers more than two-thirds of Minnesotans get their drinking water from ground water (i.e., wells). Since septic systems discharge treated sewage into the ground, ultimately traveling to the ground water, they must be properly sited, designed, built and maintained to protect human health.
For information regarding the County's standards and criteria for Septic Systems, please review County Ordinance No. 4 (PDF).
Native Seed Mixes for Mounds
If you're interested in shallow rooting native seed mixes designed for septic systems, please visit the Scott SWCD's Seed Mix page and select the septic system mix.
On-site sewage system regulation is mandated by MN Rules Chapter 7080 (as recodified in 1990) and DNR rules Chapter 6120.3400 Subd. 3B., MN Chapter 145A.05, Metropolitan Council's Development Guide, and Scott County Ordinance No. 4 (See About Us / County Ordinances). The County's Ordinance is effective Countywide with coordination of enforcement and permitting in the larger cities.
Services provided include:
- Construction inspections
- Failing systems enforcement
- Issuance of pumping/inspection permits maintenance of data
- Notification of homeowners for system inspection/maintenance on a schedule basis
- Public education
- Site approval
- As-Built Inspection Form (PDF)
- Existing Septic Tank Reuse Form (PDF)
- Above Grade Systems Management Plan (PDF)
- Below Grade Systems Management Plan (PDF)
- Holding Tank Management Plan Form (PDF)
- MPCA Compliance Inspection Form (PDF)
- MPCA SSTS Abandonment Form (PDF)
- Septic Plat Requirements Form (PDF)
- Septic Permit Application (PDF)
- Type III Monitoring Form (PDF)
- Well Pressure Test Form (PDF)
- What is a compliance inspection?
A compliance inspection is any inspection, evaluation, investigation or other such process to make conclusions, recommendations or statements regarding an individual sewage treatment system to reasonably assure that it is not a “failing system.”
- What is a failing system?
A “failing system” is any sewage system that discharges sewage to a seepage pit, cesspool, drywell, or leaching pit, any system with less than three feet of soil or sand between the bottom of the system and the saturated soil level or bedrock and any system that discharges sewage to the soil surface, into a dwelling, to surface water or a well.
- When is a compliance inspection required?
Current State Laws require a compliance inspection to be done any time a new sewage system is installed; before a local unit of government can issue a permit for the addition of a bedroom to a home; any time a permit or variance is requested to alter an existing system; and any time a sewage system is reviewed to determine if it is in compliance.
Scott County’s Ordinance also requires a compliance inspection when there is a change in use of the property (i.e. residential to commercial, commercial to industrial, or the addition of a business to a home); when new lots are developed and one of the lots has an existing sewage system; whenever a horizontal addition or an accessory structure (such as a garage, deck, or pole building) is added to a home and acceptable information is not available regarding the soil properties and/or the installation of the sewage system; and for a change from seasonal to year round use or when the Scott County Zoning Ordinance causes a system to be reviewed for compliance.
- Does Scott County require a compliance inspection whenever a home is bought or sold?
No, Scott County does not require a compliance inspection when your home is sold. However, many prospective home-buyers do choose to have one done before making their purchase decision, so that they know exactly what they are buying. Lenders may also require a compliance inspection to be done before they will finance that home purchase for the buyer.
- When does the Scott County Zoning Ordinance cause a septic system to be reviewed?
Any time a building permit is applied for and the home is in a shoreland district, the sewage system may have to be reviewed for compliance. Building permits that deal with maintenance of a home such as siding, roofing, new windows or furnace, etc., will not trigger the sewage system to be reviewed. However, the system must be reviewed for the addition of a new deck, enlargement of a deck, a garage, or a second story addition to the house. In some situations the system may be required to be replaced, and a septic permit may then have to be applied for at the same time the building permit is applied for.
- If a system is found to be “failing” when must it be repaired or replaced?
If a system poses an imminent health threat, state laws require it to be fixed within ten months. If a failing system does not pose an imminent health threat but consists of a seepage pit, leaching pit or dry well, it must be repaired or replaced between ten months to five years depending upon how susceptible the ground water is to contamination. If the system is failing because it has less than three feet of separation and it is located in an area that is not susceptible to ground water contamination, you will then have 10 years to replace your system. The ISTS Ordinance includes a table that establishes a repair/replacement schedule in accordance with the ground water protection zones defined by the Minnesota Geological Survey. View more details about the
- Will the County require replacement of a failing system if it is located in an area proposed for City Sewer?
The ordinance provides that failing systems within areas designated in an adopted plan for extension of public sewer within five years will not be required to be replaced, regardless of the groundwater susceptibility zone it is located within. The one exemption is a system that presents an imminent threat to public health. Any imminent threat to public health will need to be abated within ten days as provided in Minnesota Statutes Chapter 145A. However, this might mean routine pumping, water conservation or other measures rather than system replacement.
- If a system is relatively new, will the system still need a compliance inspection?
If the County has accurate soil information, a valid permit and the system was inspected when permitted, a full compliance inspection may not be needed. The County may be able to issue a building permit as long as the system is not currently discharging to the soil surface. If there is no soil information, no permit was issued or there appears to be discrepancies between the soil information, a compliance inspection shall be done.
- How long is a compliance inspection valid?
State statute indicates that a Certificate of Compliance for an existing system is valid for a 3 year period and a Certificate of Compliance for a new system is valid for five years, unless the local unit of government finds evidence of an imminent threat to public health and safety which requires the abandonment of the system.
- How long should an individual sewage treatment system last?
A properly installed and maintained ISTS should serve a residence indefinitely. Some factors that can shorten its service life include:
- Lack of routine maintenance, septic tank pumped to remove sludge.
- Dumping harmful chemicals into sewer, including septic additives.
- Surface water draining onto drainfield or over-sprinkling.
- Compaction of the soil over the drainfield, vehicles driven or parked on the drainfield.
- Mechanical failure of system components, baffles in the septic tank falling off, septic tank cracking or collapsing, or pump failure (if so equipped).
Bacteria is a pollutant impacting Scott County waters. The sources of E. coli are thought to originate from improperly managed livestock waste (feedlots and manure spreading), failing septic systems, untreated urban storm water, and wildlife.
In Scott County multiple streams do not meet Minnesota Pollution Control Agency’s water quality standard for bacteria (E. coli) including Big Possum Creek, Credit River, Eagle Creek, Porter Creek, Raven Stream, Robert Creek, Sand Creek, and Brewery Creek.
What Can You Do To Help?
- Make sure your septic system is functioning properly. If your septic system is failing, it could be contaminating groundwater or a nearby lake or stream. More information on septic system inspections and compliance can be found on our website: Scott County Septic Systems
- Pick up after pets. Bacteria from animal waste, including E. coli are a growing water quality concern and pet waste is a large contributor. Pet waste does not just disappear. When left on the lawn, rain water will break it apart and wash it into a local waterbody. Even if you don't live near a lake or stream, the waste will make its way into our waterbodies through storm drains. To help combat bacteria pollution, collect pet waste in plastic bags and place it in the trash.