Current Projects

2020 Aquatic Management Plan

The 2020 Aquatic Management Plan, approved last September by the Pondweed Working Group, is a mirror of the Plan carried out in the spring of 2019.


This May 6, more than 8 miles of curlyleaf pondweed infested shoreline was successfully treated in East Lake Okoboji and Lower Gar with an aquatic herbicide. (See red lanes on map-Lower Gar map unavailable.

Mechanical harvesting of curlyleaf pondweed will begin on May 19.  The cutting, gathering, hauling to shore and responsibly composting the invasive species will last 2 to 3 weeks.


This Aquatic Management project is a continuing partnership with your East Okoboji Lakes Improvement Corporation, the Iowa Department of Natural Resources, and the City of Orleans.


2019 Aquatic Management Plan

Iowa DNR starts first phase to manage the invasive curlyleaf pondweed at Iowa Great Lakes
Spirit Lake, Iowa – The Iowa Department of Natural Resources (DNR), working with the East Okoboji Lakes Improvement Corporation (EOLIC), started the first phase of the curlyleaf pondweed management strategy for the Iowa Great Lakes on April 26.

About 60 acres of curlyleaf along shorelines was treated with an herbicide approved for use on lakes to provide some relief around docks and boat ramps.

“Our first use of the herbicide in 2018 treated the areas just outside of the dock on about 4.25 miles of shoreline,” says Mike Hawkins, Iowa DNR fisheries biologist. “Last year’s application on the north end of East Okoboji Lake and Lower Gar Lake proved safe and effective treatment. This year we treated a little over 8 miles of shoreline.”

“Another five miles of trails will be created using a commercial plant harvesting system in the coming weeks,” says Hawkins. “We are also doing a 30-acre block treatment using a combination of herbicide and harvesting in the north bay of East Okoboji Lake to reduce the amount of plant material that dies off in June and help prevent a fish kill from low oxygen.”

Curlyleaf pondweed is an invasive plant first discovered in the Okoboji chain in the mid-1900s. It has been in all of the lakes since that time, but has caused navigation and lake access issues in recent years. Under the right conditions, this underwater plant can form dense mats making it hard to get through. A series of late and unseasonably warm fall seasons has allowed this plant to gain an advantage and increase in density.

“Unlike native aquatic plants, curlyleaf pondweed germinates in the fall and takes advantage of the long growing season created by mild conditions,” Hawkins says. “It grows under the ice and dies back in mid to late June. Once the plant starts to dominate, conditions for its growth improve even more because it clears the water and lets more sunlight shine through.”

Although curlyleaf pondweed is widespread and causes problems throughout the United States, management strategies are mostly limited to spot treatments while attempts to eliminate it have failed. Larger treatment area control is being investigated and evaluations are underway in Iowa and other states.

“Over the past few years, we’ve worked with the community to design a strategy to treat the plant near shore and in a series of boating paths. We’ve done this with a combination of herbicide and mechanical harvesting,” says Hawkins. Last year the group raised money and received state funding to treat 60 acres of curlyleaf. This year around 85 acres of the plant will be treated.

Terry Wilts, who has helped spearhead the local committee and is part of the EOLIC, says this isn’t an easy issue to tackle.

“We’ve worked with the Iowa DNR, local cities, businesses, and municipal water systems to develop a plan that is safe, cost effective, and considers everyone’s concerns.”

Lake shore property owners can remove plants around their docks and hoists without a permit. The plants can be cut, raked, or harvested using mechanical means only. It is not legal for private citizens to treat plants with chemicals in public waters.

“The use of herbicides by private individuals is dangerous and against the law,” Hawkins says. “Only certified professionals who are trained in aquatic application and have the necessary permits can apply herbicides to public lakes in Iowa. Aquatic herbicide application is strictly regulated to protect drinking water and all recreational users.”













2018 Aquatic Management Plan

The East Okoboji Lakes Improvement Corporation, in partnership with the Iowa Department of Natural Resources and the City of Orleans, will be using a two-prong approach in 2018 to include mechanical harvesting and herbicide application.  With the late ice-up and reduced snow early this winter curlyleaf pondweed had a great start since last fall.  We anticipate it will be another tough year based on how much pondweed was growing under the early ice.
Mechanical Harvesting
The City of Orleans has again worked with the Iowa DNR to contract for mechanical harvesting.  An inter-governmental contract was granted to the City  from the state’s Marine Fuel Tax fund.  The local match for those funds must be 25% .   We estimate this should provide funding for up to 40 acres of harvest.
Herbicide Application
A contract is in place with Aquatic Environment Consultants for the application of Aquathol K.  20 acres (10 acres in the north bay of East Okoboji and 10 acres in Lower Gar Lake) will be treated.  This represents a single pass with a boat.  The herbicide is applied under the water surface using a closed system.  Refer to the attached map below for reference on the application areas.
Application of the herbicide is water temperature and plant growth dependent and with the way things are progressing we may be looking at late April or early May.
Herbicide/Project Monitoring
Mary Skopec from Iowa Lakeside Labs is working on a plan to do water testing during and after the herbicide treatment.  DNR has funds set aside to complete this task.  DNR will be working with Dickinson County Emergency Management to plan an aerial survey of the project (both mechanical and herbicide treatment) to quantify our efforts.
Areas in red on the maps below will receive a herbicide treatment.  Areas in yellow will be mechanically harvested.  The mechanical harvesting plan is subject to change depending on conditions and growth patterns.












2017 Aquatic Management Plan

The East Okoboji Lakes Improvement Corporation, in partnership with the Iowa Department of Natural Resources and the City of Orleans, have contracted with Underwater Solutions to begin a trial harvesting of curlyleaf pondweed.

Cutting and removal of the invasive plant will begin on or around May 15, 2017.  Second cutting approximately 3 weeks later in June.

Map at right shows the navigational lanes being harvested from the Narrows north to the State Fish Hatchery.



EOLIC wants everyone to be aware of opportunities provided by Dickinson County Soil and Water Conservation District (DCSWCD) for individuals to receive grants of up to 50% match for installing a rain garden on your property if certain criteria are met. IN ADDITION, EOLIC, in our efforts to support our mission, will match 25% up to $500 on a limited number of Grants awarded by DCSWCD to OUR MEMBERS.

We believe this is a great opportunity if you have a site that would qualify. For information, contact Derek Namanny at 712-336-3782 Ext. 3 or you can contact Bill Maas or Terry Wilts. This is an excellent reason to become a member of EOLIC!


EOLIC and the Blue Water Garden Club continue to help the City of Spirit Lake maintain the demonstration ‘rain garden’ in Memorial Park. The plants are flourishing and the system is functioning very well, holding a huge amount of rain run-off and allowing it to slowly soak into the ground resulting in less debris and silt into East Lake.


Last year EOLIC applied for and received a grant for a study in East Okoboji Beach of storm water run-off before, during, and after construction of paved roads in the area. Low Impact Development practices (rain gardens and bioswales) are being installed this summer instead of a traditional storm sewer system. This is the second year of a three year study that was requested by the DNR and is being watched state wide for proof that Low Impact Development Practices are effective and worth the cost.


EOLIC is working to expand awareness of Aquatic Invasive Species (AIS) to prevent their spread into the Iowa Great Lakes. This year we paid for a new printing of the IGL BOATERS MAP, East Okoboji Lake version. This map includes AIS information and is available at boat ramps and various boating related businesses and facilities in the region. Board members also volunteered to help set up a local Tourist Information Radio station. Tune to 1640 on the AM band to hear AIS information and local weather.


EOLIC has for several years been advocating new state rules that would protect Iowa’s waters from pollution and stem the trend of declining water quality in Iowa’s lakes and streams. This spring these rules were approved by the Iowa legislators. EOLIC participated by attending public hearings, writing letters of comment, encouraging legislators, and supporting the Iowa Environmental Council as they worked with the DNR to write acceptable rules.