Waterfront Landowner Reference Guide
Rock Lake is one of our community’s greatest natural assets. Fishing, swimming, boating, and enjoying the scenic beauty are all dependent on clean water and healthy shorelands. Wisconsin’s zoning standards implemented through regulations and permits, help protect these valuable resources by ensuring sustainable development.
These zoning standards apply to the 75-foot strip of shoreland adjacent to the water’s edge, including Rock Lake, Miljala Channel, Marsh Lake and the Mill Pond. The land within 35 feet is designated the shoreland buffer where there are extensive restrictions. This webpage will guide you in making the right decisions to protect and maintain the natural beauty and health of this incredible community asset. It is intended as an overview only and does not include all rules. Additional restrictions may apply.


The first step is understanding that the waterfront land you own is subject to shoreland zoning regulations and permits. The diagram above and these definitions will help.
Ordinary High-Water Mark (OHWM): The point on the bank or shore where the presence and action of surface water is so continuous as to leave a distinctive mark such as erosion, destruction/prevention of land plants, or a predominance of aquatic plants.
Riparian owner: One who owns land along a river, stream, or other watercourse e.g. Rock Lake.
Riprap: Clean field stone or quarry stone that meets specific size requirements.
Shoreland buffer/Vegetative buffer: A highly regulated strip of land consisting of plants, shrubs and trees which extends from the OHWM inland for 35 feet. A shoreland buffer is not required within the Vision and Access Corridor. Otherwise, this buffer extends the entire length of your shoreline.
Vision and Access Corridor: This is a strip of land where an unobstructed view of the water is allowed. If your shoreline is less than 100 feet in width, then the Vision and Access Corridor can be no more than 30% (city) or 35% (county/town) of your lot width with a minimum of 10 feet (county/town). If your shoreline is 100 feet or more in width, your Vision and Access Corridor cannot exceed 30 feet (city) or 35% of your lot width with a maximum viewing corridor of 200 feet (county/town).
Rules governing Rock Lake and its shoreland are shared by multiple entities. Depending on where you live and what you want to do, consult one of the entities listed below during your planning phase. They will help you understand the codes and statutes that govern what you are able to do. When you contact them, have an idea of what work you want to perform and be aware that detailed drawings may be necessary for zoning and permit determinations. Contacting them in your planning phase can save you time, money and potential remediation.
This includes any projects within 75 feet of Rock Lake, Miljala Channel, Mill Pond, and Marsh Lake.
City of Lake Mills 200 Water Street Lake Mills WI 53551 www.ci.lake-mills.wi.us Troy Evenson, Office: (920) 648-2344 Cell: (920) 817-0468 Laws can be found under “City Code” tab at: www.ci.lake-mills.wi.us. | If you live in the Town contact Jefferson County at (920) 674-7130 (Zoning) before commencing any work. www.jeffersoncountywi.gov and the Town Building Inspector (Chris Butschke) at (608) 576-6371 | If you require a variance in the Town, |
If you live in the CITY of Lake Mills:
Boathouses: (permit required)
- One per lot, area <400 square feet
- Existing lawfully constructed boathouses may not be enlarged without a new permit
- Designed for boat storage, not habitable
- Electricity is the only public utility
- It’s an accessory structure that can’t be built prior to principal building
- Must be above OHWM and minimum of 3 feet from it
- Placed within Vision and Access Corridor (see 660-34)
- Stairs for lake and boathouse must be in Vision and Access Corridor
- Additional stipulations in Conditional Use Permit (CUP) and requirements
- more information: ecode360.com/31271824#31271824
Paths, roads, stairways and other structures
- Permit is required if within 35 feet of OHWM & shall be located within the Vision and Access Corridor
- Effectively control erosion
- more information: See E. (3) in ecode360.com/31271838
If you live in the TOWN of Lake Mills:
Boathouses (permit required):
- One per lot, area <400 square feet
- Prohibited below OHWM
- Designed for boat storage, not habitable
- Roof may be used as a deck if it has a flat roof, no side walls or screen and a railing that meets standards
- Earth tone colors required on exterior
- Main door to face water
- more information on Town (County) codes: www.jeffersoncountywi.gov/%20Board/Ordinance
Boathouses: See page 72 “Exempt Structures 1.”
Patios, Decks, Gazebos, Screen Houses (Open Sided & Screen Structures) (permit required)
- Exempt from shoreland setback if they meet certain requirements and
- 35 feet landward from OHWM
- <200 square feet
- No sides, or open or screened sides
- Approved plan for vegetative buffer zone meeting criteria
- more information on Town (County) codes: www.jeffersoncountywi.gov/%20Board/Ordinance
Decks, Gazebos, Patios, Screen Houses: See page 73 “Exempt Structures 2.”
- Exempt from shoreland setback if they meet certain requirements and
Walkways, stairways or rail systems necessary for access (permit required)
- Max of 60 inches in width
- Located in Access and Viewing Corridor
- Minimize erosion and storm water runoff
- Vegetation established and maintained to stabilize disturbed land.
- more information on Town (County) codes: www.jeffersoncountywi.gov/%20Board/Ordinance
Walkways, stairways or rail systems necessary for access: See page 73 “Exempt Structures 6. & 7.“
If you live in the City of Lake Mills:
- Piers
Here are links to codes and rules regarding placing a pier;
https://dnr.wisconsin.gov/topic/Waterways/recreation/piers.html
and
https://dnr.wi.gov/topic/waterways/factsheets/pier_planner_082012.pdf - Swimming rafts
Riparian owners may place rafts within the owner’s exclusive riparian zone, without a permit, as long as the following standards are met. - Riparian owners may place adjacent to their land
- <150 feet from shore and anchored
- <100 square feet in size
- Not placed before April 1st
- Removed by November 1st
- Additional restrictions apply
- more information; ecode360.com/31380667
If you live in the Town of Lake Mills:
- Piers
Here is a link to rules regarding placing a pier;
https://townoflakemills.org/wp-content/uploads/2020/08/5-6-Regulating-Piers-Wharves-Mooring-Buoys-Swimming-Rafts-And-Inflatables-on-Rock-Lake.pdf - Swimming Rafts
Riparian owners may place rafts within the owner’s exclusive riparian zone, without a permit, as long as the following standards are met. - Constructed in compliance with code
- Cannot interfere with public rights in navigable water or rights of riparian owners
- 1 raft or 1 inflatable but not both unless inflatable is removed daily
- Securely anchored to the lakebed without fill or cribs
- Swim raft cannot exceed 100 sq ft in area
- Within 150 feet of the owner’s shoreline and does not extend within 10 feet of the boundary of the owner’s exclusive riparian zone
- Does not exceed 38 inches in height above the water, excluding covers or ladders
- Does not include signage or fueling facilities
- Equipped with at least 4 reflectors spaced evenly around the perimeter and at least 6 inches above the waterline
The following applies to both the City and Town of Lake Mills:
- Inflatables
Riparian owners may place inflatables within the owner’s exclusive riparian zone, without a permit, as long as the following standards are met. - Constructed in compliance with code
- Cannot interfere with public rights in navigable water or rights of riparian owners
- 1 raft or 1 inflatable but not both unless inflatable is removed daily
- Securely anchored to the lakebed without fill or crib
- Inflatable does not exceed 200 square feet in area.
- Within 150 feet of the owner’s shoreline and does not extend within 10 feet of the boundary of the owner’s exclusive riparian zone
- Does not exceed 38 inches in height above the water, excluding covers or ladders
- Does not include signage or fueling facilities
- Equipped with at least 4 reflectors spaced evenly around the perimeter and at least 6 inches above the waterline
- Additional restrictions apply
- More information under ordinance 5-6 at; townoflakemills.org/ordinances-resolutions/
- Buoys
Lakeshore owners may place a mooring buoy only (with the intent ofsecuring a boat). This can be done without a permit provided it is within 150 feet of their OHWM. Mooring buoys must extend 18 inches above the waterline, be white in color with a blue band clearly visible above the waterline and be spherical or ovate in shape. In addition, the mooring buoy cannot interfere with public navigation rights or interfere with the rights of your neighbors.
If residents are interested in any other buoy, they will need to contact the DNR Recreational Warden for additional assistance. Rock Lake details are available at the Town website; https://townoflakemills.org/ordinances-resolutions/
The following applies to both the TOWN and CITY of Lake Mills:
Riprap (permit required)
Riprap is clean field stone or quarry stone that meets specific size requirements. Riprap placement or replacement, or riprap repair may be eligible for a permit exemption, but only if several requirements and limitations are met. In some instances, riprap is prohibited. The DNR permit exemption checklist can be found here: https://dnr.wi.gov/topic/waterways/documents/permitExemptionChecklists/riprap.pdf. If there are any questions, request an Exemption Determination from DNR by following the instructions on the checklist.
Seawalls (permit required)
A Sea wall is an upright structure that is installed parallel to the shore to prevent the sliding or slumping of the land and to protect the adjacent upland from wave action. New seawalls are generally prohibited (NR 328.07), though individual permits may be granted where slope exceeds 1.5 feet vertical to one foot horizontal and additional criteria are met. Seawall replacement requires a permit, and the permit eligibility criteria are detailed. A General Permit Application Checklist can be found on the DNR website: https://dnr.wi.gov/topic/waterways/documents/PermitDocs/GPs/GP-SeawallReplacement.pdf
The first step in understanding what you can do is to know if your property is adjacent to a DNR “Sensitive Area”. This essentially includes properties along Korth Bay, Schultz’s Bay, the Millpond, and Marsh Lake.
Specifically, go to: https://dnrmaps.wi.gov/H5/?Viewer=SWDV (DNR surface water data viewer). Zoom in to Rock Lake. Click on Show Layers. Click on the box next to Priority Navigable Waterways (PNW, ASNRI, PRF). Then click the + next to that. All the Sensitive Areas show up on the lake. You can also turn on a satellite view to help locate your home. In the Layers box, scroll to the bottom of the list of layers or pull the scroll bar down to the bottom. Click the box next to Air Photos. Then you can zoom in to find your property.
If it’s ambiguous whether your frontage is adjacent to a Sensitive Area, feel free to email Arthur Watkinson, DNR Water Resources Mgmt Specialist for Jefferson County, at arthur.watkinson@wisconsin.gov and he can help you with that determination.
Another option is to contact Patricia Cicero, Director of Jefferson County’s Land & Water Conservation Department, at patriciac@jeffersoncountywi.gov for assistance.
Jefferson County’s Land & Water Conservation Department will also come to your home and help you identify the aquatic plants along your frontage to determine if they are native, supporting the lake’s healthy ecosystem, or invasive.
These rules apply whether you do the work or hire a contractor. If you hire a contractor, be sure to review the DNR permit that is required for your project as well as your contractor’s certification and licensure for handling/applying chemicals. If state laws are not followed, there will be enforcement consequences.
If your property IS adjacent to a Sensitive Area:
No permit required:
Manually remove plant materials that have floated in and accumulated along the shore.
A DNR permit required:
Raking rooted plants, chemical use, or mechanical plant control. Mechanical plant control is using a machine to assist in removal of aquatic plants. This includes a process called DASH (Diver Assisted Suction Harvesting).
If your property IS NOT adjacent to a Sensitive Area:
No permit required:
• Manually remove plant materials that have floated in and accumulated along the shore.
• Rake rooted plants within your viewing corridor (up to 30’ along the shoreline which includes your pier, lifts, rafts etc). The area raked cannot change from year to year, and the plants must be removed from the water’s edge. There is no limit to how far out into the lake you can rake.
Caution: If you remove native aquatic plants through raking, you might create a situation where invasives, such as Eurasian Water milfoil, might move in. Once established, these plants will grow up to the water’s surface creating more problems than the original plantings.
A DNR permit required:
Any chemical use, or mechanical plant control. Mechanical plant control is using a machine to assist in removal of aquatic plants. This includes a process called DASH (Diver Assisted Suction Harvesting).
In order to reach open water, I need to cut a path through some aquatic plants. Is there a problem with this? If you use a motorized boat, you should establish a set path to open water to minimize disturbance of aquatic plants. You cannot deliberately use your boat to cut down aquatic plants outside this pathway, or motor back and forth with the intention of cutting plants with the propeller.
Do you need a DNR permit?
Start by emailing Arthur Watkinson at arthur.watkinson@wisconsin.gov to understand the process and what to expect. To start the application process, go to: https://dnr.wi.gov/lakes/plants/forms/
Jefferson County Water and Land Management Department did an aquatic plant survey in 2017. You can view native aquatic plants, invasive species, and why aquatic plants are an essential part of a healthy lake at: https://rocklake.org/wp-content/uploads/sites/45/2019/03/2018_ManagementPlan.pdf (See pages 45-54 in the Lake Management Plan). Another useful resource in understanding aquatic plants can be seen at: https://www.uwsp.edu/cnr-ap/UWEXLakes/Documents/resources/bookstore/WaterPlants.pdf
Where are they located? Within your Vision & Access Corridor? Outside of your Vision & Access Corridor (within the Shoreland Buffer)?
If you live in TOWN, native trees, shrubs, flowers & grasses are required for shoreland planting. If you live in the CITY native plantings are encouraged. Native plants are not only attractive, but also help prevent erosion, flooding, algae blooms, damage to fisheries, as well as loss of habitat and privacy. Native plants will also deter geese as they prefer lawns with unobstructed views. (See question Why should I use Native Plantings? and Where can I find Information on Native Plantings?)
Within your Vision & Access Corridor:
If you live in the CITY of Lake Mills: The shoreline must be planted with a groundcover from OHWM to 10 feet inland. Native groundcovers are encouraged. Beyond this 10-foot buffer, you are allowed to prune trees/shrubbery. For more detail go to this link: City of Lake Mills Land Use Legislation/Zoning Regulations 660-34 Shoreline Preservation and Vision and Access Corridor. https://ecode360.com/31271838
If you live in the TOWN of Lake Mills: Vegetation may be removed but adding fill or grading is prohibited. Owners are encouraged to control erosion with native plantings.
Outside of your Vision & Access Corridor or within your Shoreland Buffer:
If you live in the CITY of Lake Mills: Routine pruning of trees/shrubbery may be done; however, it cannot jeopardize the health and viability of the trees/shrubs. Planting native trees, shrubs, flowers & grasses is encouraged.
If plantings, trees, or shrubbery are removed then mitigation and restoration or partial restoration may be required. Please note that an alternative cutting plan allowing greater cutting may be permitted by the Plan Commission by issuance of a Conditional Use Permit (CUP). Conditional uses are those which have the potential to create undesirable impacts on nearby properties. These impacts can be difficult to determine except on a case-by-case basis and are therefore subject to procedural requirements beyond the zoning district including, but not limited to, a public hearing process.
If you live in the TOWN of Lake Mills: You must contact Jefferson County before you begin your work. With the proper permits, the county has allowed owners to remove damaged or diseased trees. You will be required to replant native plants/trees in their place. Please call to get the appropriate permits. For more detail go to this link: Jefferson County Zoning Ordinance Shoreland Provisions, pp 74-75 – last amended 10/9/2018. www.jeffersoncountywi.gov/%20Board/Ordinance
Where are they located? Within your Vision & Access Corridor? Outside of your Vision & Access Corridor (within the Shoreland Buffer)?
Please note: If you live in TOWN, native trees, shrubs, flowers & grasses are required for shoreland planting. If you live in the CITY native plantings are encouraged. Native plants are not only attractive, but also help prevent erosion, flooding, algae blooms, damage to fisheries, as well as loss of habitat and privacy. Native plants will also deter geese as they prefer lawns with unobstructed views. (See question Why should I use Native Plantings? and Where can I find Information on Native Plantings?)
Within your Vision & Access Corridor:
If you live in the CITY of Lake Mills: The shoreline must be planted with a groundcover from OHWM to 10 feet inland. Native groundcovers are encouraged. Beyond this 10-foot buffer, you are allowed to remove plantings. For more detail go to this link: City of Lake Mills Land Use Legislation/Zoning Regulations 660-34 Shoreline Preservation and Vision and Access Corridor. https://ecode360.com/31271838. Removal of invasive species is also allowed. Verify they are invasive before removal. (Defined here 271-3 and 271-6) (See question, How do I know a plant is invasive? And Why is it important to remove invasive plants?)
If you live in the TOWN of Lake Mills: Vegetation may be removed but adding fill or grading is prohibited. Owners are encouraged to control erosion with native plantings.
Outside of your Vision & Access Corridor or within your Shoreland/Vegetative Buffer:
If you live in the CITY of Lake Mills: Removal of invasive species is allowed. Verify they are invasive before removal. (Defined here 271-3 and 271-6) (See question How do I know a plant is invasive? And Why is it important to remove invasive plants?)
A permit is required for other vegetative removal. Use of native plants are encouraged.
If plantings are removed, mitigation and restoration or partial restoration may be required. Please note that an alternative cutting plan allowing greater cutting may be permitted by the Plan Commission by issuance of a Conditional Use Permit (CUP). Conditional uses are those which have the potential to create undesirable impacts on nearby properties. These impacts can be difficult to determine except on a case-by-case basis and are therefore subject to procedural requirements beyond the zoning district including, but not limited to, a public hearing process.
If you live in the TOWN of Lake Mills: You must contact Jefferson County before you begin your work. With the proper permits, the county has allowed owners to remove invasive species. You will be required to replant native plants/trees in their place. Please call to get the appropriate permits. For more detail go to this link: Jefferson County Zoning Ordinance Shoreland Provisions, pp 74-75 – last amended 10/9/2018. www.jeffersoncountywi.gov/%20Board/Ordinance
(See question How do I know a plant is invasive? And Why is it important to remove invasive plants?)
Native plants are not only attractive, but they also help prevent erosion, flooding, algae blooms, damage to fisheries, as well as loss of habitat and privacy. Native plants will also deter geese as geese prefer lawns with unobstructed views.
Why native plants for shoreland owners?

Shoreland native plants help the shoreline stand up to fluctuating water levels, moving ice, boat wakes and wind driven waves. Their deep root systems can preserve your shoreline. How? One third of their deeply penetrating roots die per year, allowing water to infiltrate into the soil, cleaning the water for our ground water and keeping the lake clean from yard runoff. According to UW Extension Lakes, the lawn-to-lake shoreline allows 7 to 9 times more phosphorus to enter the lake compared to native plants. (Phosphorus is a plant nutrient and more of it entering the lake means more algae resulting in lower water quality.) For many lots, “the phosphorus yield to the lake due to a poor shoreline buffer may exceed the phosphorus yield from ALL other sources.” Another way the deep roots of native plantings reduce nutrients entering Rock Lake is by slowing storm water down, spreading the flow out, and cutting the erosive potential of runoff. Erosion soil brings a readily usable form of nitrogen into the lake which also fuels algae growth.
Native plantings can help increase your privacy and reduce boat noise from the water. They also help preserve habitat providing a place to hide, rest, and nest. Once established, they do not require fertilizers or regular watering– ultimately reducing maintenance costs.
One other critical factor for choosing native plants is captured in this quote by Doug Tallamy: “The question is no longer simply whether natives are better than nonnatives. It’s whether ecologically productive plants are better in our landscapes than ecologically destructive plants.” What is an “ecologically productive plant”? One which supports the backbone of our ecosystem—insects and the pollinators. According to numerous research studies, native plants support the life cycles of 10 to 100 times more insect species than nonnative plants. Our insects have spent eons developing food webs with our native plants. Insects cannot simply transfer to an introduced ornamental species—even species that have been introduced 100 years ago. Research indicates that once a yard exceeds 30% non-native plantings, the productivity of that yard begins to decrease. Read more at: Plant Choice Matters https://homegrownnationalpark.org/tallamy/not-in-our-yard-doug-tallamy
Here is a link to help you find Native Plants specific to your location.
https://www.nwf.org/NativePlantFinder/
and
Here is a listing of Wisconsin Native Plant Nurseries.
Invasive plants are extremely resilient and may spread to your neighbor’s property or even other natural areas such as Tyranena or Korth Park. According to a 2007 study, about 85% of invasive woody plant species in the US are escapees

from our gardens. (Kaufman and Kaufman) Invasives are resilient because our local ecosystem doesn’t recognize them. They squeeze out native plants and reduce the variety of plants that your property supports. Butterflies won’t be able to rear their young on them. Native bees won’t recognize their nectar. Local caterpillars will not see them as a food source. Once that happens, songbirds will not be able to feed their young and will avoid your yard. Quite simply, invasive plants do not contribute to the web of life in your yard.
The DNR separates invasive plants into: restricted and prohibited. Restricted means that the plant is already established in Wisconsin and it can cause significant environmental, economic or human health harm. Residents are encouraged to remove these plants and should not plant them (even if they are sold at nurseries). Prohibited means that the plant is not currently found in Wisconsin, with the exception of small pioneer stands, and that if introduced into the state, are likely to survive and spread, potentially causing significant environmental, economic or human health harm. Residents must contact the DNR with a prohibited species and may receive DNR help to eradicate them.
If you need help in identifying if weeds/plants are invasive species, check out: https://dnr.wisconsin.gov/topic/Invasives. There are also apps such as Great Lakes Early Detection Network (GLEDN), which is a free online system that collects invasive species reports from casual observers, verifies these reports and integrates them with other networks. The system then uses this integrated information to send customized early detection email alerts. The City of Lake Mills also defines invasive species here: 271-3 and 271-6.
Some common invasive plants in/around Lake Mills include:
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Check the Healthy Lakes website (http://healthylakeswi.com/) and contact the Jefferson County Land and Water Conservation Department for further information and financial assistance (lwcd@jeffersoncountywi.gov 920-674 -7111).
LINKS for more Information:
Waterfront Landowner Reference Guide (printed 4 page brochure)
Butterflies seen in Jefferson County, Wi. & their Host Plants
Safeguarding Our Shorelands for the Future (DNR)
Sensible Shoreland Lighting: discusses the issue of light pollution, with a special focus on issues surrounding shoreland lighting.
Minnesota Shoreland Management Resource Guide
more information on natural plantings on our ‘LINKS‘ page
Disclaimer: Several of the images used on this page have been copied from governmental sources. We make no claim to them and they are not copyrighted by us.