The Greenprint

Hickory Grove Lake, like many lakes in Iowa, has some very common health issues. Sediment loading, nutrient loading, and bacterial impairment are the major concerns.

• Hickory Grove Lake is also on the bacterial impaired waters list for E. Coli. 
• On average, around 756 tons of sediment per year enter this lake.
• Optical brighteners, found in today’s laundry detergents, are found in the lake.
• Algae blooms from high nutrient levels take over the lake giving it a green appearance.   
• A high population of carp disrupt shallowly rooted plants, muddying the water and releasing phosphorus that increases algae abundance.

The Hickory Grove Watershed Advisory Team was developed with authorities in conservation, lakes restoration, water quality, and soil health. This group developed The Hickory Grove Lake Watershed Management Action Plan, which is being used as a road map to solve problems in the watershed.

• All septic systems in the watershed, 9 total, were replaced to ensure their proper function. 
• A crucial private land owner in the watershed had extensive work completed, including:
  • Development of a pond and fencing to exclude cattle from directly entering the water.
  • Streambank stabilization efforts and a grade control structure were installed.
  • A saturated buffer was installed to collect water and remove nitrates.

Planning to address in-lake work has been under way by the Iowa DNR Lakes Restoration, DNR Fisheries, and DNR Engineering teams, in collaboration with Story County Conservation. A three phase in-lake work plan was created. This three year plan is an ongoing effort and therefore subject to change.

• Phase 1 efforts, which will occur this spring before the lake is drawn down, include shoreline stabilization by the campground and numerous rock check dams to prevent erosion in gullies throughout the park.
• Phase 2 of the plan addresses the drawdown structure. This will include repairing the existing outlet structure and adding an additional pipe for drawdown. The lake will only be drawn down one foot per day to discourage sloughing of the banks and is planned for the summer of 2018.
• Phase 3 construction is scheduled to begin in the fall of 2018, after the lake bed has dried out. This includes shoreline work, mechanical dredging, fish habitat and access improvements, and then a complete fishery renovation.

A project of this great size and scope wouldn’t be possible without the cooperation and coordination of all the various contributors. Over 15 different groups have assisted with this project planning and work. Story County Conservation is just one part of this grand project. We want to continue making a difference in water quality by educating our citizens of its importance and showing its significance. Projects like this are a perfect opportunity to do just that!

Fishing regulations may also be relaxed prior to drawdown at the discretion of Iowa DNR and SCC officials. This decision will depend on the timing of project phasing, which is dependent on funding allocation. Stay tuned for an exact date for drawdown as this exciting project moves forward.