Once known for its diverse sport fish population, Bass Lake, a small lake in northeastern Marinette County, Wisconsin, was gaining a reputation for severe nonpoint source pollution.
Bass Lake is a 36-acre drainage lake with a watershed area of less than one
square mile, and a maximum depth of 62 feet. According to Greg Sevener, watershed
specialist with the Department of Natural Resources, Bass Lake was placed on
the Wisconsin 303(d) list of impaired waters because of high phosphorus, low
dissolved oxygen levels and fish kills.
“Runoff from cropland, livestock barnyards and nutrient accumulation
in a wetland through which the inlet drained delivered high levels of nutrients
and biological oxygen demand to the lake,” says Sevener. The nutrient
overload caused heavy algae blooms to cover the lake, depleting oxygen levels
in the lake and killing fish.
Marinette County Land and Water Conservation District (LWCD) led clean-up
efforts, enlisting the two livestock operation landowners, Wisconsin Department
of Natural Resources (DNR), Town of Beaver, U.S. Fish and Wildlife Service
and a Wisconsin DNR lake modeling expert to aid in returning the Lake to a
healthy body of water.
Eliminating Runoff
Bass Lake had been a small-scale priority lake project in the ’80s.
But according to Sevener, practices like vegetated filter strips, even though
they were considered state-of-the-art at the time, really didn’t control
the pollution source. “The barnyards were too close to the lake for filter
strips to completely eliminate or prevent further runoff,” he explains.
In 1998, the county received a grant of $150,000 from the DNR under a program
that allowed conservationists to target key sources of runoff.
The plan at the time was to offer each of the two farmers directly adjacent
to the lake money to apply practices. However, one landowner voluntarily
discontinued farming, so the state was able to put critical land into conservation
easement. “We were able to use funds from the stewardship program to
put 2,000 feet of Bass Lake shoreline and 55 acres of cropland under permanent
easement,” says Greg Cleereman, district conservationist for the Marinette
County LWCD.
The LWCD and remaining landowner worked together to further reduced runoff
by moving the animals to a free stall facility, keeping the cows indoors. In
addition, a sediment control basin and a leachate collection system were installed
to collect polluted runoff and pump it directly into the manure storage, virtually
eliminating polluted runoff from livestock areas.
Further Clean-up Needed
After the BMPs were in place, the LWCD knew it would take many years for the
water to clear. “The biggest source (of phosphorus) left was internal
loading,” says Richard Wedepohl, DNR section chief. The phosphorus in
the lake sediment would “recycle” for years and continue to cause
blue-green algae blooms.
The Marinette LWCD worked with a professional consultant and a DNR lake modeling
expert to plan and execute treatment of the lake with alum, a chemical that
binds with phosphorus in the lake sediments to prevent recycling. The Wisconsin
DNR Lake Protection Grant Program funded 75 percent of the alum treatment,
while Marinette LWCD cost-shared 25 percent.
According to Wedepohl, Bass Lake shows definite signs of recovery after just
six years. “We’re not getting the blue-green algae blooms. The
vegetation is showing improvement. The fish population is healthy — there are
bass, green sunfish, forage fish and northern pike in the lake.”
More to the Success
The clean-up of Bass Lake took several years, many man hours and nearly $700,000.
The Total Maximum Daily Load targets were achieved and Bass Lake is slated
to be removed from the state’s 303(d) list in the next listing cycle.
“The key to the success of this project was the partnerships involved.
It was a true partnership,” says Cleereman. “The county did the
lion’s share of the work and they made the commitment to work with the
farmers and develop relationships.”
He adds, “These are voluntary programs and if we don’t have a
level of trust and cooperation with the producers, nothing will happen.”
Cleereman says, “Another lesson everyone can learn from this project
is the importance of having regular staff funding,” adds Cleereman. “It
takes about two years of working with the county to really learn what you need
to build relationships with farmers.”
