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Lakes
In Apple Valley
Did you know...
The City of Apple Valley has a number of lakes. The
following are some activities that are done throughout the year to help
manage the City's lake resources.
Alimagnet
Loosestrife Beetles. Natural Resources
staff have been collecting loosestrife beetles for release on wetlands
adjacent to Alimagnet Lake since 2003. They are released into a City-owned
wetland near Lake Alimagnet infested with purple loosestrife annually.
Purple loosestrife is one of the exotic plants brought in from Europe
long ago because it was a "pretty" and hardy perennial plant.
As it has no natural enemies in the United States, the plant has become
a major threat to many wetlands where it can out-compete native plants
and take over the entire wetland. Loosestrife beetles are natural enemies
from Europe which have been researched and found to feed exclusively
on Purple loosestrife plants. The beetles have been imported, raised,
and released into wetlands as a biological control of Purple loosestrife.
It often takes five to seven years for beetle populations to become
established and built up significantly for effective control. The loosestrife
beetle collection program is coordinated through the Minnesota Department
of Natural Resources.
Aerator. Each
winter since 1999, an aeration system has been operated on Lake Alimagnet
to prevent winter fish-kill. The aeration system creates a large area
of open water to facilitate oxygen exchange and increased levels of
dissolved oxygen. The system is designed to support 90 percent of the
existing fish population.
The aerator is permanently
installed on the southeast side of the lake. The initial purchase of
the aerator and installation cost was a joint venture among the cities
of Apple Valley and Burnsville, and the Alimagnet Lake Association.
Ongoing costs for electrical power, maintenance, and winter monitoring
are split between the two cities.
Each year in late December
or early January, THIN ICE warning signs are installed around the perimeter
of the anticipated open water area. Warning signs are a requirement
of the annual Minnesota Department of Natural Resources’ aerator
permit and must be maintained throughout winter aerator operation. Generally,
the aeration system runs January through March except during periods
of warmer weather. City staff monitors the aerator site on a daily basis.
In the recent past, dissolved
oxygen levels have been monitored monthly at the aerator site and in
the Burnsville bay. The Burnsville bay represents a neutral site providing
data that would be expected if no aeration system were present. Collected
data has shown significant decreases in dissolved oxygen levels in the
Burnsville bay as winter progressed. Although dissolved oxygen levels
at the aerator site drop throughout winter, they remain well above levels
required to support fish. There has not been a significant winter fish-kill
in Lake Alimagnet since the aeration system has been in operation.
Monitoring. Alimagnet Lake is currently enrolled in the Citizen
Assisted Monitoring Program (CAMP), organized by the Metropolitan Council.
Through CAMP, citizen volunteers collect water quality samples every
other week throughout the summer. Samples are tested and analyzed by
the Metropolitan Council. Data gathered from this volunteer monitoring
program is used to help make lake management decisions.
For more information on the CAMP
program, check out their website;
Or to volunteer,
Contact City of Apple
Valley staff.
Carbon Amendment Application. Since 2005, the City of Apple
Valley and City of Burnsville have applied a carbon amendment in the
form of cracked corn to Alimagnet Lake. Carbon amendments reduce occurrences
of algal blooms in lakes by giving harmless bacteria a food source,
which allows the harmless bacteria to ingest Phosphorus before blue-green
algae can use it and cause algal blooms. The use of cracked corn represents
a safe way to control algae that will not harm people or wildlife using
the lake.
Fish Management. The Cities of Apple Valley and Burnsville have undertaken
a project to remove excess bullheads and sunfish from Alimagnet Lake
under MNDNR permit. Alimagnet Lake has an unbalanced fish population
that is contributing to water quality problems. Disproportionate amounts
of sunfish and bullheads in Alimagnet Lake are stirring the bottom sediments
of the lake and releasing phosphorus into the water column causing deleterious
algal blooms. All other fish and animals trapped in nets are released
back into Alimagnet Lake.
For more information on Alimagnet Lake activities, check out the Alimagnet
Lake Lake Management Plan 
(19 MB);
Or,
Go to the MnDNR
Lake Finder website.
Cobblestone
Cobblestone lake is a large manmade regional pond used for the treatment
of stormwater that the City of Apple Valley actively monitors.
Monitoring. Cobblestone Lake is currently enrolled in the Citizen
Assisted Monitoring Program (CAMP), organized by the Metropolitan Council.
Through CAMP, citizen volunteers collect water quality samples every
other week throughout the summer. Samples are tested and analyzed by
the Metropolitan Council. Data gathered from this volunteer monitoring
program is used to help make lake management decisions.
Farquar
The City of Apple Valley is currently in the process of drafting a
lake management plan for Farquar and Long Lakes will be completed in
2007. The lake management plan will guide City of Apple Valley activities
regarding management and improvement of the lakes.
Monitoring. Farquar Lake is currently enrolled in the Citizen
Assisted Monitoring Program (CAMP), organized by the Metropolitan Council.
Through CAMP, citizen volunteers collect water quality samples every
other week throughout the summer. Samples are tested and analyzed by
the Metropolitan Council. Data gathered from this volunteer monitoring
program is used to help make lake management decisions.
For more information on the CAMP
program, check out their website;
Or to volunteer,
Contact City of Apple
Valley staff.
For more information on Farquar Lake, check out the MnDNR
Lake Finder website.
Keller
Ferric Chloride Injection System. The Black Dog Watershed Management
Organization, a water management organization that lies partially within
Apple Valley, has operated a Ferric Chloride injection system on Crystal
and Keller Lakes since the 1996. Ferric Chloride is a harmless chemical
that prevents algal blooms by removing phosphorus, a nutrient blue-green
algae needs to multiply, from the water column through chemical reactions.
The system pulls water from the bottom of Crystal Lake in Burnsville,
mixes the water removed from Crystal Lake with Ferric Chloride, and
adds the treated water to Keller Lake through the stormwater system.
Because Crystal and Keller Lakes are connected through pipes, both lakes
benefit from the water treatment. There may be an additional benefit,
in that amounts of Curlyleaf pondweed, a harmful exotic plant, appear
to have been reduced since operation of the system began.
Exotic Weed Removal. Since 2004, the City has participated in
harvesting of Curlyleaf pondweed in Keller Lake. Approximately 25 of
the 63 surface water acres is included in the annual harvest, the maximum
allowed by the Minnesota Department of Natural Resources weed harvesting
permit. Curlyleaf pondweed is an exotic plant that reproduces by a vegetative
structure similar to a seed, called a turion. Repeated annual harvesting
can significantly reduce the occurrence of curlyleaf pondweed by limiting
the amount of turions available to germinate the following year. Removing
curlyleaf also reduces competition with native aquatic plants, allowing
the native plants to become established and further ward off curlyleaf
pondweed. Additionally, in-lake phosphorus is reduced by removing plant
biomass, which ties up considerable amounts of phosphorus while growing.
The curly leaf harvesting project is a joint venture between the Cities
of Apple Valley and Burnsville.
Monitoring. Keller Lake is currently enrolled in the Citizen
Assisted Monitoring Program (CAMP), organized by the Metropolitan Council.
Through CAMP, citizen volunteers collect water quality samples every
other week throughout the summer. Samples are tested and analyzed by
the Metropolitan Council. Data gathered from this volunteer monitoring
program is used to help make lake management decisions.
For more information on the CAMP
program, check out their website;
Or to volunteer,
Contact City of Apple
Valley staff.
For more information on Keller Lake activities, check out the
Black Dog Watershed Management Organization;
Or,
Go to the the MnDNR
Lake Finder website.
In 2004, the City participated in harvesting of Curlyleaf pondweed
in Keller Lake. Approximately 25 of the 63 surface water acres was included
in the harvest, the maximum allowed by the Minnesota Department of Natural
Resources weed harvesting permit. Curlyleaf pondweed is an exotic plant
that reproduces by a vegetative structure similar to a seed, called
a turion. Repeated annual harvesting can significantly reduce the occurrence
of curlyleaf pondweed by limiting the amount of turions available to
germinate the following year. Removing curlyleaf also reduces competition
with native aquatic plants, allowing the native plants to become established
and further ward off curlyleaf pondweed. Additionally, in-lake phosphorus
is reduced by removing plant biomass, which ties up considerable amounts
of phosphorus while growing. The curly leaf harvesting project is a
joint venture between the Cities of Apple Valley and Burnsville.
Lac Lavon
Monitoring. Lac Lavon is currently enrolled in the Citizen Assisted
Monitoring Program (CAMP), organized by the Metropolitan Council. Through
CAMP, citizen volunteers collect water quality samples every other week
throughout the summer. Samples are tested and analyzed by the Metropolitan
Council. Data gathered from this volunteer monitoring program is used
to help make lake management decisions.
For more information on the CAMP
program, check out their website;
Or to volunteer,
Contact City of Apple
Valley staff.
For more information on Lac Lavon check out the
Lac Lavon Lake Management Plan
(1 MB);
Or,
Go to the the MnDNR
Lake Finder website.
Long
The City of Apple Valley is currently in the process of drafting a
lake management plan for Long and Farquar Lakes will be completed in
2007. The lake management plan will guide City of Apple Valley activities
regarding management and improvement of the lakes.
Monitoring. Long Lake is currently enrolled in the Citizen Assisted
Monitoring Program (CAMP), organized by the Metropolitan Council. Through
CAMP, citizen volunteers collect water quality samples every other week
throughout the summer. Samples are tested and analyzed by the Metropolitan
Council. Data gathered from this volunteer monitoring program is used
to help make lake management decisions.
For more information on the CAMP
program, check out their website;
Or to volunteer,
Contact City of Apple
Valley staff.
For more information on Long Lake, check out the MnDNR
Lake Finder website.
Content updated on:
29-Dec-2006
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