In addition to kicking off the alum application project today, the lake was busy with many visitors and observers. A group gathered Monday afternoon to participate in the Spring Lake Alum Demonstration Day. Participants were able to observe and learn more about the plan and goals for the lake restoration project. Dr. John Holz (HAB)…
HAB spent Sunday afternoon and Monday morning preparing equipment for the Spring Lake alum application project. This included assembly of the barge’s application boom, launching the barge into the lake, setting up on-shore storage tanks and confirming the delivery plan for the alum. A construction fence was installed around the staging area to keep lake…
The Spring Lake alum application is scheduled to begin and we invite anyone who is interested in seeing the operation in person, to please join us at the Spring Lake boat launch (2025 Lakeview Drive, Jordan) on Monday, May 21st at 2pm. We will be giving a brief demonstration and can answer any questions at that time.
Aluminum is considered a non-essential metal because sh and other aquatic life do not need it to function. There is a large body of scienti c literature documenting the safe use of alum in lake environment conditions, which has allowed the North American
Lake Management Society to fully endorse its use (NALMS, 2017).
Alum has been repeatedly shown to be safe for humans. Alum is a common
food additive and has also been used for decades to clean our drinking
water before consumption. HAB uses the exact same drinking water certi ed
alum when preforming a lake improvement application.
Alum (aluminum sulfate) is a nontoxic liquid that
is commonly used in water treatment plants to
clarify drinking water. It’s use in lakes began in
the early 1970’s and is used to reduce the amount
of phosphorus in the water. Lower amounts of phosphorus lead to lower amounts of algae and the symptoms associated with poor water quality. Alum is most often used to control phosphorus release from the lake bottom sediments (internal loading). Research has shown that even when external sources of phosphorus from the surrounding watershed are lowered, the internal cycling can continue to support signi cant nuisance algal blooms.
Phosphorus enters lakes from two sources. Phosphorus entering the lake from outside sources are called external sources. These sources originate in the watershed and are either directly rinsed into the lake or ow to a stream that enters the lake. Common external sources include lawn fertilizers, septic systems, agricultural practices, stormwater, soil erosion and geese: anything that causes phosphorus to enter the lake from the watershed.
Once the external source of phosphorus enters the lake, it is deposited in the lakebed and is recycled back into the water column. This is the second source of phosphorus and it originates from within the lake itself. This is called an internal source and these inputs are most common during the summer
and winter when water oxygen concentrations are low or zero near the bottom. This condition causes changes in the chemistry of the lakebed that lead to the phosphorus leaching out of the sediment and into the water.
Lake property is aesthetically and economically desirable throughout the world and it is well-established that property values are tightly linked to the quality of the lake.
Cyanobacteria (a.k.a. blue-green algae) are a type
of algae which can produce toxins and are often found in lakes with high phosphorus concentrations. Human exposure to cyanobacteria can lead to skin irritation, allergic reactions, gastrointestinal symptoms and respiratory problems. Pets and livestock are more likely to drink large quantities of lake water, potentially resulting in illness and/or death.
The nutrient of concern in lakes is phosphorus. Algae, like terrestrial plants, require phosphorus to grow.
Algae are microscopic, free- oating organisms that are commonly found in lakes. They are similar to terrestrial plants in that they also require sunlight and nutrients to grow. Algae are the important base of the aquatic food web that ultimately supports juvenile
and adult sh. However, the excessive growth of
undesirable types of algae (Cyanobacteria) causes severe water quality problems. Cyanobacteria (a.k.a. blue-green algae) thrive when nutrients are high and are capable of producing toxins. They grow rapidly to cause blooms and scums and are usually associated with nearly all lake water quality problems.
Spring Lake is a 600-acre lake located in central Minnesota near the town of Prior Lake. Spring Lake is a highly valued recreational resource that supports swimming, boating and fishing activities. However, the high nutrients have led to excessive amounts of algae that interfere with the use of the lake. In 2011 the Prior Lake-Spring…