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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.
Cobblestone LMP
Final Report
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:
25-Jun-2010
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