Introduction

 

Purpose of the Plan

The City of Shell Lake, Wisconsin has abundant water resources.  Shell Lake (2,580 acres) and Round Lake (28 acres) are completely within the city limits, as are most of Little Ripley Lake (47 acres) and part of Chain Lake.  The city limits encompass 6500 acres.  

Recognizing the need to protect its lakes, the city organized an Inland Lake Protection District in 1978.  A Lake Protection Advisory Committee (LPAC) made up of six members was established in 1982. The Lake District Board of Commissioners, comprised of the Mayor and city aldermen, charged the LPAC with the development of a lake management plan in 1996.  The lake management plan was to address land use within the watershed, recreational uses of lakes, water quality, and shoreline restoration.  The committee was also directed to be a sounding board for public opinion on these issues and to assist with public information and training of personnel involved in implementing and enforcing actions that affect lakes and their watersheds.  Recommendations from the advisory committee are to be brought to quarterly meetings of the Board of Commissioners.

Property owner surveys, water quality studies, and a hydrologic budget for Shell Lake provided background information for the preparation of this document.

Recognizing that recreational, scenic, and economic values of lakes correlate directly with healthy lake ecosystems, this plan emphasizes responsible stewardship for the entire community of Shell Lake.   For healthy lakes, all residents and visitors to the City of Shell Lake must act as stewards of these valuable public resources.  Environmental as well as economic concerns must guide development throughout the watershed.

Responsible stewardship means that:

1. Individual property owners implement land management practices designed to protect water quality including restoring the elements of natural shorelines.

2. City of Shell Lake governing boards and officials

a. enforce existing ordinances governing lakeshore development,

b. guide development in a manner that protects lake water quality and habitats into the future, and

c. support educational efforts.

3. The Lake Protection Advisory Committee provides education, seeks public involvement, and continues to guide lake management.


Plan Goals

The plan is structured around five major goals that were identified by the Lake Protection Advisory Committee:

Guide environmentally and economically sound development around city lakes.

Maintain or improve the water quality of city lakes.

Protect and enhance natural scenic beauty.

Protect and restore aquatic and shoreland habitat for fish and wildlife species.

Maintain or improve water-related recreational experiences while minimizing impacts to lake ecosystems.

Background 

Physical Characteristics

Shell Lake

Shell Lake is the largest land-locked lake in Wisconsin covering approximately 2,580 acres. There is no natural outlet.  The maximum depth of the lake is approximately 36 feet.

The watershed of Shell Lake encompasses 12.7 square miles and extends into four townships in Washburn County:  Bashaw, Beaver Brook, Barronett, and Sarona.  The ratio of watershed to lake area is approximately 3 to 1.   Figure 1 provides a map of the lake and land uses in the watershed.  Several small intermittent streams and one storm channel flow into Shell Lake.

The lake basin was formed by glacial action, although there is evidence that the present size and shape of the lake was influenced by beaver activity along the northwest shoreline.  Glacial deposits around the lake form a blanket of sediment up to 300 feet thick over the sandstone bedrock.  These glacial deposits are covered primarily by northern silt upland soil, however the northwest side is covered with northern loamy upland soil.

Little Ripley Lake

Little Ripley is a 47-acre lake with a maximum depth of 14 feet.  The lake has dark brown stained water and an abundance of vegetation.  The lake is elongated east to west and has a steeply sloping, irregular shoreline.  Upland hardwoods surround the entire lake.  The watershed tributary to Little Ripley Lake is approximately 400 acres, about 8 times the surface area of the lake.  Figure 2 is a watershed map for Round Lake and Little Ripley Lake.

Round Lake

Round Lake is a 28-acre lake with a maximum depth of 27 feet.  The lake is a seepage lake with no surface water inlets or outlets except that the lake is connected to Chain Lake.  The watershed tributary to Round Lake is about 342 acres or 12 times the surface area of the lake.

Watershed Land Use

Historical Land Use

Prior to 1880, few people lived in the area, and it was heavily forested with white pine.  A sawmill was built on the northwest side of the lake in 1881, and approximately 1500 settlers formed the Village of Shell Lake.  Farming became the primary industry in the early 1900’s after most of the area was deforested.  The population of the village declined during this transformation.  A few lakeshore homes existed then, however, interest in lakeshore property did not develop until the 1940’s.

Current Land Use

Shell Lake

The Shell Lake watershed consists of forestland (30 percent), agriculture (24 percent), wetland (14 percent), and urban area (8 percent).

Little Ripley Lake

The watershed of Little Ripley Lake is largely undeveloped (86%), and is primarily forestland (64%).  Agricultural land makes up 5 percent of the watershed, and residential land makes up 11 percent of the watershed.  The remaining area (an additional 20 percent) was not described in the study, but appears to be the lake and wetlands.

Round Lake

The watershed of Round Lake is largely undeveloped (62%).  It consists of forestland (46%), residential (2%), agricultural (17%), water (including the lake ­ 15%), and wetlands (2%).8

Shoreline development

An informal survey of parcels was conducted within the city limits on each lake in August 1998.  The numbers of developed and undeveloped parcels were as shown in Table 1.

These counts did not include any parcels judged unavailable for development including those owned by the City of Shell Lake or the Wisconsin Department of Natural Resources (WDNR) and a small number of parcels in common family ownership.  It was assumed that these commonly owned parcels would not be sold and developed due to privacy considerations. 

Water Quality

Introduction of nutrients to a lake, which can occur both internally from lake sediments and externally from runoff water, is called nutrient loading.   Nutrient loading can lead to increased algae growth and decreased water clarity.  Lawn fertilization and agricultural runoff are some of the external sources of nutrient loading.  Nutrients also attach to sediments carried in runoff water from areas of bare soil such as construction sites and crop fields.                    

Poor water clarity is associated with excessive amounts of the nutrient phosphorus in most lakes.  As the level of phosphorous increases in a lake, a corresponding increase in algae growth and chlorophyll occurs, and lake clarity decreases.

Lake water clarity can be measured using a secchi disk, a black & white circular disk that is lowered into the water until it can no longer be seen.   The depth reading taken at that point is the secchi depth.  Ongoing secchi disk monitoring helps to track water quality trends and to identify the impacts of land use management practices on water quality.

Shell Lake

Shell Lake has historically been a clear lake with low levels of phosphorous. Figure 3 shows that phosphorous levels are generally near .01 milligrams/liter.  Over the past decade, secchi disk readings for Shell Lake have typically been greater than 10 feet as indicated in Figure 4.  This puts Shell Lake in the category of a mesotrophic lake, a clear lake with moderate nutrient levels. 

Little Ripley Lake

Barr Engineering completed Phase I of a study relating to the water quality of Little Ripley Lake in 1998.  Little Ripley has an average summer phosphorus level of 0.03 milligrams/liter putting it in a nutrient rich or eutrophic category.  The average summer secchi disk measurement was 4.3 feet, also in the eutrophic category.  The Barr study recommends more detailed analysis of the tributary watersheds, consideration of future development impacts, and examination of agricultural practices in the watershed.

Round Lake

Barr Engineering completed Phase I of a study relating to the water quality of Round Lake in 1998.  Round Lake is a mesotrophic lake with an average summer phosphorus concentration of 0.017 milligrams per liter.  The average summer secchi disk measurement is 7.9 feet.  The Barr study recommends more detailed analysis of the tributary watersheds, consideration of future development impacts, and examination of agricultural practices in the watershed.