What's the problem with Hannen Lake?
Although the water quality is adequate at Hannen Lake, a number of factors in the watershed hold the future for the 37-acre lake in Benton County. Sediment from the watershed runs off fields and into the lake, delivering thousands of tons of sediment from sheet and rill erosion annually. Eventually, sediment ends up in streams and is delivered to Hannen Lake. Excess sediment delivered to the lake can reduce water clarity, damage habitat of aquatic life, fill in streambeds, clog drainageways and deliver phosphorous.

Those looking to preserve the water quality at Hannen Lake are also battling nitrogen and phosphorus, two of the most common nutrients found in Iowa. These nutrients come from manure and chemical fertilizers used for agriculture and in urban areas. Nutrients like this can cloud the water, create low oxygen and high ammonia levels, lead to poor aquatic life diversity and even speed up the natural aging process of the lake.
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What's being done to help Hannen Lake?
The Hannen Lake Watershed Project has a number of conservation practices for farm and country living. Landowners in the Hannen Lake watershed can improve the lake by partnering with the Hannen Lake Watershed Project.

James Brown, watershed project coordinator, can work with you to evaluate your property and identify practices that can help both the creek and your property. Brown can also help find financial assistance to install those practices. Landowners participating in the watershed project can generally get improved financial assistance opportunities.

The Hannen Lake Watershed Project began in the 1980s and continues to improve the overall water quality of the lake. Key objectives of the program include reducing current sediment and external phosphorus loading by 60 percent. A second component will be livestock oriented programs that will enable area producers to address various threats to water quality in the lake. The program, which will include field days, informational meetings, education programs, signage and news releases, will also seek to increase awareness of the beneficial aspects of various practices among residents. An informational kiosk will be installed in the park to help educate the public about the program and provide them with an opportunity to express their ideas and comments to help shape the project's future agenda.

In order to improve water quality in the Hannen Lake watershed, conservation practices like terraces, grassed waterways, grade stabilization structures and filter strips are being used.

Terraces are an efficient practice in reducing soil erosion and sediment in the 605-acre watershed. Terraces are built around a hillside and either slow runoff and guide it to the bottom of the hill or collect runoff and store it until the runoff can be absorbed by the ground. Terraces must be properly designed and maintained to combat erosion.

Grassed waterways are an effective practice in reducing soil erosion. These natural or constructed channels move surface water across the land without causing soil erosion. The vegetation in the waterway slows the water, protecting the land from rill and gully erosion.

Grade stabilization structures are used to lower water levels while protecting soil from gully erosion.

Filter strips are strips of grass or other vegetation used to trap sediment (and pollutants attached to it) from runoff.
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What can I do to help?
Landowners can consider installing conservation practices to control the amount of sediment, nutrients and other pollutants reaching Hannen Lake.

Financial assistance is available, and the benefits extend beyond cleaner water - often conservation practices can produce financial benefits, create recreational opportunities and provide habitat for wildlife.

IOWATER is a possible option for residents of Hannen Lake. Monitors collect information on the levels of nitrates, nitrites, dissolved oxygen, pH, chloride and phosphate in the lake.

Some monitors also report on the water's temperature and color, and on biological life in the monitoring area, which is often an indicator of water quality.

Monitors report their data to the IOWATER online database, where the public can view water monitoring results from across the state at IOWATER.
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What is the future of Hannen Lake?
Although a fairly small lake and watershed, a number of conservation practices are in full swing to improve the watershed and with continued efforts from landowners, visitors to the lake will continue to enjoy all it has to offer.
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Meet the project coordinator
James Brown grew up in Waterloo, Iowa and attended Iowa State University. He graduated in 1977, majoring in agronomy and forestry. Brown became district conservationist in Benton County in 1982.

"I take pleasure in getting conservation practices on the ground," said Brown.

For other ways you can get involved with the Hannen Lake Watershed Project, contact James Brown, watershed coordinator, at (319) 472-5274 or James.Brown@ia.usda.gov
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Project partners

• Iowa DNR
• Iowa Department of Agriculture - Division of Soil Conservation
• USDA Natural Resources Conservation Service

For More Information
Local:
James Brown
Hannen Lake Watershed Project Coordinator
(319) 472-5274
James.Brown@ia.usda.gov
Benton County NRCS Office

Statewide:
Steve Hopkins
DNR Nonpoint Source Program Coordinator
(515) 281-6402
Stephen.Hopkins@dnr.iowa.gov