Lac Sault Dore (Soo Lake), Elk River Watershed (UC09)
Lac Sault Dore (Soo Lake), Elk River Watershed (UC09)
Lac Sault Dore (Soo Lake) (2236800)
600.83 Acres
Natural Community
Natural communities (stream and lake natural communities) represent model results that use predicted flow and temperature based on landscape features and related assumptions. Ranges of flow and temperature associated with specific aquatic life communities (fish, macroinvertebrates) help biologists identify appropriate resource management goals. Wisconsin Natural Communities.
Year Last Monitored
This is the most recent date of monitoring data stored in SWIMS. Additional surveys for fish and habitat may be available subsequent to this date.
This is impaired
Impairment Unknown, Excess Algal Growth
Total Phosphorus
Trout Water 
Trout Waters are represented by Class I, Class II or Class III waters. These classes have specific ecological characteristics and management actions associated with them. For more information regarding Trout Classifications, see the Fisheries Trout Class Webpages.
Outstanding or Exceptional 
Wisconsin has designated many of the state's highest quality waters as Outstanding Resource Waters (ORWs) or Exceptional Resource Waters (ERWs). Waters designated as ORW or ERW are surface waters which provide outstanding recreational opportunities, support valuable fisheries and wildlife habitat, have good water quality, and are not significantly impacted by human activities. ORW and ERW status identifies waters that the State of Wisconsin has determined warrant additional protection from the effects of pollution. These designations are intended to meet federal Clean Water Act obligations requiring Wisconsin to adopt an 'antidegradation' policy that is designed to prevent any lowering of water quality - especially in those waters having significant ecological or cultural value.
Impaired Water 
A water is polluted or 'impaired' if it does not support full use by humans, wildlife, fish and other aquatic life and it is shown that one or more of the pollutant criteria are not met.

Fish and Aquatic Life

Current Use
The use the water currently supports. This is not a designation or classification; it is based on the current condition of the water. Information in this column is not designed for, and should not be used for, regulatory purposes.
Shallow Lowland
Shallow lowland lake describes the depth and location of the lake in a watershed. These variables affect the lakes response to watershed variables.
Attainable Use
The use that the investigator believes the water could achieve through managing "controllable" sources. Beaver dams, hydroelectric dams, low gradient streams, and naturally occurring low flows are generally not considered controllable. The attainable use may be the same as the current use or it may be higher.
Aquatic Life
Waters that support fish and aquatic life communities (healthy biological communities).
Designated Use
This is the water classification legally recognized by NR102 and NR104, Wis. Adm. Code. The classification determines water quality criteria and effluent limits. Waters obtain designated uses through classification procedures.
Streams capable of supporting a cold water sport fishery, or serving as a spawning area for salmonids and other cold water fish species. Representative aquatic life communities, associated with these waters, generally require cold temperatures and concentrations of dissolved oxygen that remain above 6 mg/L. Since these waters are capable of supporting natural reproduction, a minimum dissolved oxygen concentration of 7 mg/L is required during times of active spawning and support of early life stages of newly-hatched fish.


Lac Sault Dore (Soo Lake), in the Elk River Watershed, is a 600.81 acre lake that falls in Price County. This lake is managed for fishing and swimming and is currently considered impaired.

Date  2015

Author   Aquatic Biologist

Historical Description

Lac Sault Dore is a soft water, drainage impoundment on the Elk River. The dam, a concrete roller with stop logs, has a 10-ft head and is owned by the City of Phillips and the Town of Elk. The main purpose of this water is for recreation. The impoundment has an outlet flow estimated to the 122.8 ft(3)sec.
Besides the Elk River, the lake receives flow from Crane and Chase Creek, Carpenter Creek, and one unnamed feeder stream in Section 7. The lake has an irregular shoreline and 10 islands, totalling 137 acres. Its fishery consists of muskellunge, northern pike, walleyes, perch, largemouth bass, small-mouth bass, bluegills, black crappies, rock bass, pumpkinseeds, yellow bullheads, white suckers, redhorse and minnows.

Upland hardwood and pine cover 90% of the lake shoreline, and several small tag alder swamps and leatherleaf bogs make up the remainder. The littoral bottom is mainly sand with scattered areas of gravel and muck. Emergent, floating and submergent aquatic vegetation are common throughout the lake. Muskrats are an important furbearer, and a large number of ducks nest along the lake's 1,000 acres of wetland. Other ducks and geese use the lake during their migrations. Private development consists of 5 resorts, 5 boat rentals and 120 cottages or homes. Public access is available form three
sites, none of which are adequate. Source: 1983, Surface Water Resources of Price County Lac Sault Dore, T37N, RIW-2W, Section 1, 7, 11-13 Surface Area = 561.0 acres, Maximum Depth = 21 ft, MPA = 47 ppm, Secchi disk = 4 ft

Date  1983

Author   Surface Water Inventory Of Wisconsin

Lac Sault Dore (Soo Lake), Elk River Watershed (UC09) Fish and Aquatic LifeLac Sault Dore (Soo Lake), Elk River Watershed (UC09) RecreationLac Sault Dore (Soo Lake), Elk River Watershed (UC09) Fish Consumption

Impaired Waters

Lac Sault Dore (Soo Lake) (WBIC 2236800) was placed on the impaired waters list for total phosphorus in 2012. The 2018 assessments showed continued impairment by phosphorus; new total phosphorus sample data exceeded the 2018 WisCALM listing thresholds for the Recreation use and Fish and Aquatic Life use. Chlorophyll-a sample data clearly exceeded the REC thresholds, but clearly met the FAL use thresholds. Based on the most updated information the impairment of Excess Algal Growth was added to the Total Phosphorus listing. This water was not meeting its designated uses and was considered impaired.

Date  2017

Author  Ashley Beranek

Impaired Waters

Lac Sault Dore (Soo Lake) (2236800) was placed on the impaired waters list for total phosphorus in 2012. The 2016 assessments showed continued impairment by phosphorus; total phosphorus sample data exceeded 2016 WisCALM listing thresholds for the Recreation, however, chlorophyll data do not exceed REC thresholds. Total phosphorus and chlorophyll data clearly met thresholds for Fish and Aquatic Life use. Based on the most updated information, no change in existing impaired waters listing is needed.

Date  2015

Author  Aaron Larson


Wisconsin has over 84,000 miles of streams, 15,000 lakes and milllions of acres of wetlands. Assessing the condition of this vast amount of water is challenging. The state's water monitoring program uses a media-based, cross-program approach to analyze water condition. An updated monitoring strategy (2015-2020) is now available. Compliance with Clean Water Act fishable, swimmable standards are located in the Executive Summary of Water Condition in 2018. See also the 'monitoring and projects' tab.



Protect Riparian or Shorelands
Price County is sponsoring a project to restore 250 feet of shoreline habitat along the Elk River. There is an unstable 25 foot face that is actively eroding and needs to be stabilized. Fish- wildlife habitat and water quality will be improved. Project goals: 1) Reduce sediment and nutrient delivery; 2) Reduce instream sedimentation to improve fish spawning habitat; 3) Restore shore land habitat for wildlife; 4) Improve water quality; 5) Protect existing resources.

Management Goals

Wisconsin's Water Quality Standards provide qualitative and quantitative goals for waters that are protective of Fishable, Swimmable conditions [Learn more]. Waters that do not meet water quality standards are considered impaired and restoration actions are planned and carried out until the water is once again fishable and swimmable

Management goals can include creation or implementation of a Total Maximum Daily Load analysis, a Nine Key Element Plan, or other restoration work, education and outreach and more. If specific recommendations exist for this water, they will be displayed below online.


Monitoring the condition of a river, stream, or lake includes gathering physical, chemical, biological, and habitat data. Comprehensive studies often gather all these parameters in great detail, while lighter assessment events will involve sampling physical, chemical and biological data such as macroinvertebrates. Aquatic macroinvertebrates and fish communities integrate watershed or catchment condition, providing great insight into overall ecosystem health. Chemical and habitat parameters tell researchers more about human induced problems including contaminated runoff, point source dischargers, or habitat issues that foster or limit the potential of aquatic communities to thrive in a given area. Wisconsin's Water Monitoring Strategy was recenty updated.

Grants and Management Projects

Monitoring Projects

Watershed Characteristics

Lac Sault Dore is located in the Elk River watershed which is 261.12 miĀ². Land use in the watershed is primarily forest (51.70%), wetland (37.40%) and a mix of grassland (4.70%) and other uses (6.20%). This watershed has 254.00 stream miles, 2,883.84 lake acres and 49,382.72 wetland acres.

Nonpoint Source Characteristics

This watershed is ranked Not Ranked for runoff impacts on streams, Low for runoff impacts on lakes and Low for runoff impacts on groundwater and therefore has an overall rank of Low. This value can be used in ranking the watershed or individual waterbodies for grant funding under state and county programs.However, all waters are affected by diffuse pollutant sources regardless of initial water quality. Applications for specific runoff projects under state or county grant programs may be pursued. For more information, go to surface water program grants.

Natural Community

Lac Sault Dore (Soo Lake) is considered a Reservoir under the state's Natural Community Determinations.

Natural communities (stream and lake natural communities) represent model results and DNR staff valiation processes that confirm or update predicted conditions based on flow and temperature modeling from historic and current landscape features and related variables. Predicated flow and temperatures for waters are associated predicated fish assemblages (communities). Biologists evaluate the model results against current survey data to determine if the modeled results are corect and whether biological indicators show water quaity degradation. This analysis is a core component of the state's resource management framework. Wisconsin's Riverine Natural Communities.