Blake Fk, Middle Grant River,Upper Grant River Watershed (GP05, GP06)
Blake Fk, Middle Grant River,Upper Grant River Watershed (GP05, GP06)
Blake Fork (962000)
17.23 Miles
0 - 17.23
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.
Cool-Cold Headwater, Cool-Cold Mainstem, Macroinvertebrate, Cool-Warm Mainstem
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 river is impaired
Degraded Biological Community, High Phosphorus Levels
Unknown Pollutant, 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.
Fish and Aquatic Life - waters that do not have a specific use designation subcategory assigned but which are considered fishable, swimmable waters.
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.
Streams capable of supporting a warm waterdependent sport fishery. Representative aquatic life communities associated with these waters generally require cool or warm temperatures and concentrations of dissolved oxygen that do not drop below 5 mg/L.
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.


Blake Fork is a spring and seepage stream (Smith and Ball, 1971) beginning near Patch Grove and flowing to the Grant River west of Lancaster. Agricultural non-point sources of pollution, particularly sediment from farm fields and eroding banks appear to major problems in the watershed. Some barnyards and at least one animal transfer site may also be problems. Smallmouth bass have been found at two sites on Blake Fork during fish surveys done in 1995-1996 (Wang, 1996). Index of Biotic Integrity (IBI) scores and stream water quality ratings, indicators of environmental degradation, for Blake Fork ranged from fair to poor. In-stream habitat evaluations show Blake Fork to have generally fair habitat quality (Wang, 1996). Macroinvertebrate samples found nearly 70% of the samples to be midges, while conversely, only about 12% of the samples were stoneflies, mayflies or caddisflies (Marshall, 1999). High numbers of midges typically suggest some sort of environmental degradation usually as a result of agricultural non-point source pollution (Gamman, 1983). These data, coupled with the local intensely agricultural land use, indicates the stream is affected by non-point sources of pollution. The stream is considered a high priority for a non-point source pollution abatement project.

Bloomington and Patch Grove both operate permitted wastewater treatment plants that discharge to Blake Fork. Review of DNR wastewater files indicates that the Bloomington and Patch Grove facilities are generally operating well

Date  2001

Author   Aquatic Biologist

Historical Description

From: Smith, Tom D., and Ball, Joseph R., Lake and Stream Classification Project. Surface Water Resources of Grant County, Department of Natural Resources, 1972. Surface Area = 16.2, acres, Length = 16.7 miles, Gradient = 20 ft./mile, Flow = 12.8 c.f.s.

A spring- and seepage-fed stream beginning within the Vil!age.of Patch Grove. It flows southeast
through Bloomington and then into the Grant River six miles west 9f Lancaster. About 90 percent of this water- shed has been cleared for agricultural purposes and the stream flows through firm pasture land for its entire length. Flooding is common. The stream is characterized by areas of long flat pools and heavily eroded banks. Farm animals and feed lots are frequently seen along these seriously-eroded banks. Several portions of this stream have been straightened by the local farmers in an effort to lessen these erosion problems, only to cause more of a problem downstream. Smallmouth bass provide a limited sport fishery. Crappies and rock bass were stocked at one time. Forage fish are common and bait dealers have seined minnows from this stream in previous' years. This stream has been heavily polluted in the past and portions of the stream appeared polluted when this survey was conducted in 1970. The Communities of Patch Grove and Bloomington are considered potential pollution sources at the present time.

Game assets include muskrats and some migratory waterfowl which may utilize the stream throughout the year. The stream is accessible from ten bridge crossings with 35 dwellings situated along the banks.

Date  1972

Author   Surface Water Inventory Of Wisconsin

Blake Fk, Middle Grant River,Upper Grant River Watershed (GP05, GP06) Fish and Aquatic LifeBlake Fk, Middle Grant River,Upper Grant River Watershed (GP05, GP06) RecreationBlake Fk, Middle Grant River,Upper Grant River Watershed (GP05, GP06) Fish Consumption

Impaired Waters

Blake Fork (962000) was placed on the impaired waters list for total phosphorus in 2012. This water was assessed during the 2016 listing cycle; the regional biologist recommended an additional listing for degraded biological community based on current and historical Poor mIBI scores. This water is considered impaired and not meeting its Fish and Aquatic Life use.

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.


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

Blake Fk is located in the Middle Grant River watershed which is 79.86 miĀ². Land use in the watershed is primarily agricultural (48.80%), grassland (37.40%) and a mix of forest (9.70%) and other uses (3.90%). This watershed has 206.44 stream miles, 6.02 lake acres and 0.00 wetland acres.

Nonpoint Source Characteristics

This watershed is ranked Medium 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.This water is ranked High Stream for individual Rivers based on runoff problems and the likelihood of success from project implementation.

Natural Community

Blake Fork is considered a Cool-Cold Headwater, Cool-Cold Mainstem, Macroinvertebrate, Cool-Warm Mainstem under the state's Natural Community Determinations.

Natural communities (stream and lake natural communities) represent model resultsand 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.

Cool (Cold-Transition) Mainstem streams are moderate-to-large but still wadeable perennial streams with cold to cool summer temperatures. Coldwater fishes are common to uncommon, transitional fishes are abundant to common, and warm water fishes are uncommon to absent. Headwater species are common to absent, mainstem species are abundant to common, and river species are common to absent.

Cool (Cold-Transition) Headwaters are small, usually perennial streams with cold to cool summer temperatures. Coldwater fishes are common to uncommon (<10 per 100 m), transitional fishes are abundant to common, and warm water fishes are uncommon to absent. Headwater species are abundant to common, mainstem species are common to absent, and river species are absent.

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