North Lake, Oconomowoc River Watershed (UR09)
North Lake, Oconomowoc River Watershed (UR09)
North Lake (850800)
440.45 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.
Two-Story
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.
2024
Poor
 
This lake is impaired
Impairment Unknown
Total Phosphorus
 
Waukesha
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.
No
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.
No
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.
Yes

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.
Restricted Aquatic Life
Fish and Aquatic Life communities are not fully supported in this ecosystem.
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.
Default FAL
Fish and Aquatic Life - Default Waters do not have a specific use designation subcategory but are considered fishable, swimmable waters.
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.
Default FAL
Fish and Aquatic Life - Default Waters do not have a specific use designation subcategory but are considered fishable, swimmable waters.

Overview

North Lake is a multiple-basin, 437-acre lake in outwash deposits associated with the interlobate moraine. The lake is drained by the Oconomowoc River and is unimpounded. The water is clear and the bottom is primarily sand and gravel with scattered marl beds. The fishery consists of pan fish, northern pike, walleyes and largemouth bass. Cisco are also present and afford some winter angling opportunities. Public access is unimproved and difficult via the inlet stream. Wetlands contiguous with the outlet are of some importance for upland game birds and waterfowl.

The North Lake Management District, North Lake Voluntary Association and North Lake Environmental Protection Association exist, but only the lake management district has been active with WDNR in the last five years.

In 1991, the North Lake Management District received a Wisconsin Lake Management Planning Grant to examine historical water quality using a sediment dating and diatom identification technique. Sediment distribution in the inlet was also assessed. The report noted that sedimentation rates ranged from 0.16 g/cm2/yr to 0.037 g/cm2/yr, showing an apparent change in the water quality based upon the diatom frustule found in the sediment cores. This change corresponds to the failure of the Funks dam in 1975. The dam was located approximately 1.3 miles upstream of the lake. In 1992, WDNR removed the dam and drew down the impoundment as an emergency measure, since the dam needed significant repair but the owner refused to maintain it. The report also concluded that fine erosion material entering North Lake via the Oconomowoc River is not deposited in the shallow inlet bay area.

WDNR has been working with the lake management district to develop a comprehensive lake management plan. Some of the issues raised as a result of the Funks Dam removal project will be incorporated into this comprehensive plan.

Date  2002

Author   Aquatic Biologist

Historical Description

Source: 1963, Surface Water Resources of Waukesha County North Lake T8N, R18E

A multiple basin lake in outwash deposits associated with the interlobate moraine. The lake is drained by the Oconomowoc River and is unimpounded. The water is clear and the bottom is primarily sand and gravel save for scattered marl beds. The fishery consists of pan fish, northern pike, walleyes and largemouth bass. Cisco are also present here and afford some winter angling opportunity. Public access is at present unimproved and difficult via the inlet stream. Swampland contiguous with the outlet is of some importance for upland game birds and waterfowl.

Surface Acres = 437, S.D.F. = 1.81, Maximum Depth = 78 feet

Date  1963

Author   Surface Water Inventory Of Wisconsin

North Lake, Oconomowoc River Watershed (UR09) Fish and Aquatic LifeNorth Lake, Oconomowoc River Watershed (UR09) RecreationNorth Lake, Oconomowoc River Watershed (UR09) Fish Consumption

Impaired Waters

North Lake (WBIC 850800) was placed on the impaired waters list for total phosphorus in 2014. 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 did not exceed the REC or FAL use thresholds. Based on the most updated information, no change in the existing impaired waters listing was needed.

Date  2017

Author  Ashley Beranek

Impaired Waters

North Lake (850800) was placed on the impaired waters list for total phosphorus in 2014. The 2016 assessments showed continued impairment by phosphorus; total phosphorus sample data exceed 2016 WisCALM listing thresholds for the Recreation use and Fish and Aquatic Life use, however chlorophyll data do not exceed REC or FAL thresholds. Based on the most updated information, no change in existing impaired waters listing is needed.

Date  2015

Author  Aaron Larson

Condition

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.

Reports

Recommendations

Nutrient Budget Development
North Lake Management District is sponsoring project to complete a sediment and nutrient study for the Oconomowoc River Watershed with the following goals: 1) Estimate watershed sediment, phosphorus, and pollutant sources and loads of the River 2) Evaluate sediment accretion/erosion/transport within the Monches Millpond and the River downstream of the Dam 3) Complete in-stream bank and bed survey 4) Examine sediment and riverbed stability within the former Funks Millpond 5) Communicate results and recommendations to the District, WDNR, and other interested parties. Project deliverables: completion of a comprehensive report including the following elements: 1) Historical, present-day, and planned future land use information to help estimate phosphorus, sediment, and select pollutant loads, 2) Mapped changes to sediment deposits created by using digital orthophotography to evaluate changes to sediment bars and general channel form within the Monches Millpond and the River downstream and related to changes during and immediately after dam reconstruction/removal will also be mapped, 3) On-water survey data including: channel form, sediment types and distribution, debris jams and channel obstructions, eroding banks and unstable channel form, riparian vegetation, and potentially other factors. Attention will be given to channel stability in the former Funks impoundment, millrace, and dam area. 4) Discussion of project background issues, conclusions, and recommendations generated will be in a format useful to the WDNR and average Lake user.

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

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

North Lake is located in the Oconomowoc River watershed which is 130.86 miĀ². Land use in the watershed is primarily agricultural (24.90%), forest (19.70%) and a mix of wetland (16.90%) and other uses (38.40%). This watershed has 136.99 stream miles, 2,858.66 lake acres and 11,105.19 wetland acres.

Nonpoint Source Characteristics

This watershed is ranked Not Available for runoff impacts on streams, Not Available for runoff impacts on lakes and High for runoff impacts on groundwater and therefore has an overall rank of High. 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

North Lake is considered a Two-Story 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.

Shallow headwater lake describes the depth and location of the lake in a watershed. These variables affect the lakes response to watershed variables.