Our Lakes & Watershed

Our lakes are a part of a significant hydrological system which has many inter-related components. For us, these lakes form the "Headwaters" of the Manitowish River, a small but significant flowage that ultimately finds its way to the Mississippi River.

The High, Fishtrap, and Rush lake system is in an extremely lake-rich area of northern Vilas County and is located inside the boundaries of the Northern Highland American Legion State Forest. Within a four-mile radius of any of our shorelines, there are over thirty named lakes. Approximately forty percent of our combined shorelines are owned and controlled by the State of Wisconsin, broken down as follows: High Lake is thirty-five percent, Rush Lake is sixty-six percent and Fishtrap Lake is thirty-nine percent. Additionally, on High Lake there are many feet of shoreline which are privately owned, but totally undeveloped.

Portions of our lakes are located in three separate townships within Vilas County. The bulk of our waters and frontage is in Boulder Junction Township, with the northwestern corner of High Lake in Presque Isle Township and the eastern two-thirds of High Lake in Land O'Lakes Township. For interested researchers, there is a great deal of information on our lakes available on the Wisconsin DNR website under “Lakes." Watershed and wetland information is also available on the U.S. Geologic and Natural History Survey (USGS) website. It may be helpful to know the WBIC (water body identification code-Wisconsin DNR): High Lake - 2344000, Rush Lake - 2343600, and Fishtrap Lake - 2343200. Our lakes did not always follow the shoreline boundaries that we see today.

High, Rush, and Fishtrap Lakes are known as drainage lakes with two minor streams coming into the system and with one out-flowing stream that forms the headwaters of the Manitowish River. One of the two in-flowing streams enters High Lake through a culvert underneath County Highway B at the public boat landing channel. A small stream, Grassy Creek, flows out of Grassy Lake and enters Rush Lake through the Turtle Pond culvert underneath Ridge and High Pines Roads. In contrast with drainage lakes, water levels of a seepage lake are a function of the underlying water table and are thus more prone to the effects of drought or heavy precipitation activity. An excellent example of a large, seepage lake near us is Black Oak Lake which is located near Land O' Lakes off of county Highway B. Oswego and Jute Lakes, located nearby, are also seepage lakes.

Our lakes have been the subject of water quality, clarity, and chemistry analysis for a number of years. They have been given a mesotrophic status index which is indicative of an intermediate level of nutrient productivity, usually identified with clear water, submerged plants, and a modest level of nutrients. The trophic state is defined as the total weight of the biomass in a given body of water at any periodic measurement date. The quantities of nitrogen, phosphorous, and other useful nutrients are the primary measures defining a lake's trophic state. When such nutrient levels are increased, dramatic changes in lake condition can occur, such as low oxygen levels or exploding algae growth.

Our local watershed area is defined as the Fishtrap Dam Watershed and it encompasses fifty-seven square miles in Vilas County. Our connected open water, in theory, totals approximately 2300 acres and includes our three lakes as well as Partridge Lake (234 acres), Grassy Lake (228 acres), Nixon Lake (110 acres) and the approximately 600 acres associated with the Manitowish River flowage to the Fishtrap Dam. Notable seepage lakes in our watershed include Jute Lake (194 acres), Big Gibson Lake (116 acres), Dorothy Dunn Lake (77 acres), and Oswego Lake (68 acres).

The eastern end of our watershed is a wetland and lowland complex which is virtually void of roads. Key components that make up the over 5000-acre wetland complex in our area include Johnson Creek (2 sq. mi. or 1280 acres), McGinnis Creek (1.9 sq. mi. or 1220 acres), Siphon Creek (1.2 sq. mi. or 770 acres), Garland Creek (1.1 sq. mi. or 700 acres), Nixon Creek (.7 sq. mi. or 450 acres), Partridge Creek, and Grassy Lake (each .5 sq. mi. or 320 acres). Wetland and lowland complexes tend to provide greater hydrologic stability to watersheds during spring thaws and periods of greater precipitation as is certainly the case with our area.


Current measurements would indicate that High Lake covers approximately 740 acres, although historical surveys from 1941 would indicate 764 acres. It encompasses 6.6 miles of shoreline, 2.3 miles of which is owned by the State of Wisconsin. The lake has somewhat of an appearance of two connecting bowls—one running east and west while the other runs north and south. The central portion of the east-west bowl is fairly devoid of structure, with depths ranging from twenty to thirty feet with a sand and muck bottom. The north and west shorelines are rich with aquatic vegetation with the south shore experiencing quicker depth drop-offs and a rockier floor. The east end of this bowl ends with the significant rock structure formed by glacial drift residue. The main features of this area are the lake floor bumps experienced on an eastward drift toward Battleship Island, and the lengthy north-south rock bar which runs between Battleship and Bear Islands.

The north-south bowl is characterized by dense, aquatic vegetation as approximately two-thirds of the area has depths of fifteen feet or less. The main feature of this portion of the lake is Frog Island, which is approximately 1200 feet long and 350 feet wide. Over half of this island is low and wet. As one drifts southward from Frog Island, the bowl descends to twenty-five-foot depths with the presence of deeper aquatic plant beds. The eastern shore of this end of the lake offers spectacular visual experiences in the late afternoon and at sundown and is an amateur photographer's paradise.

The main public access to High Lake is via the slough at the northeastern end of the lake which ends at Highway County B. Starting in 2015, the High-Fishtrap-Rush Lakes Association implemented a Clean Boats Clean Waters program where students from one of the state universities conducted a boat-monitoring program with the objective of keeping invasive species out of the lake system. Our lake system experiences one of the highest daily use rates in Vilas County and the bulk of the access is through this public boat landing.

Current measurements would indicate that Fishtrap Lake covers 339 acres, and, not unlike High Lake, a 1941 historical survey indicates greater acreage—in this case, 356 acres. While Fishtrap is about half the acreage of High Lake, its shoreline measures a nearly comparable amount—6.3 miles—with 2.5 miles of this shoreline being state-owned. This lake is characterized by bowls at both ends of the lake, which are inter-connected via a series of bays and narrows, dotted with three prominent, humped islands. One of the features of the lake is the fact that it is impossible to see much more than about thirty percent of the total shoreline from any given vantage point, often giving the impression of a totally private environment.

For the most part, Fishtrap Lake is a relatively shallow lake. There are twelve easily-defined bays throughout the lake area where most of the water is less than fifteen feet deep and saturated with heavy aquatic plant beds. The main geological submerged structures on the lake are well-defined sand and rock bars at either end of the narrows opening up to the main bodies of water. The deepest part of the lake is somewhat of a hole, several hundred yards from the large bay which feeds into the Manitowish River. The lake bottom is primarily muck with a narrow strip of sand running the entire perimeter of the lake. The one anomaly to this is a sand bar which juts out from a point on the eastern shore directly across from the eastern-most island. This is most likely a function of a combination of the prevailing westerly winds and the sandy sediment drift coming through the culvert from Rush Lake.

There are four ecologically rich wetland areas (excluding the river entrance) which sustain wonderful and plentiful wildlife habitats, each located in one of the four corners of the lake. With a canoe, kayak, or any other watercraft, any naturalist or curious individual with a good set of binoculars and a camera can enjoy hours of peaceful nature viewing.


Rush Lake is the intermediary body of water between High and Fishtrap Lakes. In the period preceding the construction of any of the versions of the Fishtrap Dam, this area would have been in the form of a wetland with a meandering stream or creek. Currently, Rush Lake occupies approximately forty-three acres and has a maximum depth of seven feet. Sixty-six percent of what would be construed to be shoreline is owned by the State of Wisconsin. Within this forty acres are shallow wetlands which abut both sides of the navigable channel. The area is rich in wildlife and is regularly inhabited by nesting loons. The Grassy Lake drainage system meanders into Rush Lake through Grassy Creek and Turtle Pond and through the culvert under Ridge Road into the southwestern portion of the lake.

History enthusiast will find it interesting that there was originally a bridge over the waterway between Fishtrap and Rush Lakes until the middle 1950s. The bridge was replaced by an earthen embankment and a large, corrugated steel culvert which remains today.

Turtle Pond Fall Colors


Within one mile of our three High, Fishtrap, and Rush lakes, are many smaller natural lakes—unnamed, water-filled glacial potholes, bogs, and wetlands. Four named lakes include Sime (east of High Lake), Bambi (north of High Lake near Forest Lodge), and parts of Oswego and Big Gibson Lakes. The area west of High Lake contains two unnamed small lakes just south of High Lake Road, and Grassy Creek Flowage (Turtle Pond). There is one unnamed lake to the west of Fishtrap Lake.

“Turtle Pond” (officially Grassy Creek Flowage), known to some as Beaver Pond, is approximately a forty acre man-made impoundment of Grassy Creek to the west of High Pines Road and south of Ridge Road. The pond was created in the 1950s by using the existing High Pines roadbed as a dike and restricting the flow of Grassy Creek in order to create a fish-rearing pond. This was done under an agreement between a local sportsmen’s club and the State of Wisconsin—likely the Wisconsin Conservation Department. The pond and roadway rest on state forest land with the Town of Boulder Junction having an easement for the road. The use of the pond for musky-rearing was short-lived. The pond was not able to sustain fish over the winter due to low oxygen levels and ice. As an aside, there is some folklore that would suggest that the Willems family of High Lake formalized the Turtle Pond name, for its abundance of turtles, by staking a cardboard sign in the ground in the late 1980s.

Pond water levels were originally controlled by a level-control structure and an emergency overflow culvert. There is no record of the pond dam having ever been licensed or certified. The level-control structure has been inoperable for many years, leaving the flow to exit into the back wetlands of Rush Lake only through the emergency overflow, with the pond level always at maximum. Several high-water events in two recent years (2012 and 2014) have caused the flowage level to rise above the overflow culvert and to damage High Pines Road. The most serious damage was in 2014 when the culvert and a section of the road washed out downstream. The flowage did not completely drain due to quick action by Boulder Junction town officials. Two new culverts were installed at the previous elevation.

Bringing the dam system up to current standards, primarily by repairing or replacing the level- control structure, has been discussed but there are no current plans to do so. The dam does not have hazard signage and the culvert inlets are not protected. Dam ownership responsibilities have not been taken by the State of Wisconsin or the town of Boulder Junction. While the pond remains a popular and picturesque amenity for folks traveling there, its future is not ensured. The pond is accessible by canoe or kayak from High Pines Road.

Opportunity for personal study: For those people who are bird-watchers, photography enthusiasts, and just plain nature enthusiasts, our lakes and surrounding wetlands and uplands provide a wealth of opportunities for capturing the beauty of nature, the landscapes, and the sunsets. If you do some paddling, keep your eyes peeled for the possibility of a wood turtle, a threatened species here in Wisconsin which is reported to inhabit the “Turtle Pond” (Grassy Creek Flowage) area near Rush Lake. In general, our area abounds with beautiful and rare plants and animals. Several State Natural Areas (a defined program of the Wisconsin DNR with detailed information on their website) are nearby which are designated to protect our native plant and animal communities and are accessible for your personal visits.