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	Paved Surfaces Mean Increased Water Runoff

When we develop natural areas for urban land uses, drastic changes in water flow patterns result. Roads, streets, buildings, roofs, parking lots prevent rain from soaking into the soil. Therefore more water runoff results. In the metro lakes watersheds, this water goes into the storm water drains and then into the metro lakes. The problem is, this runoff carries pollution.

Figure 1 show which kinds of land usage typically have the most paved surfaces overall. Then Figure 2 shows where the rain goes when there is more pavement. The greater the runoff in the watershed, the more important it is to keep pollution out of the storm water drains.

Figure 1: Impervious Cover Percentages

Impervious Cover= streets, parking lots, roofs, etc.

Figure 2: Pavement Percentages and Runoff Flow

Source: Protecting Water Quality in Urban Areas, Best Management Practices for Minnesota.@ Minnesota Pollution Control Agency. (1989)

	Lake Watershed Councils Making an Impact

Lakes Appreciation Week is June 30- July 7, 2002. The North American event is sponsored by the North American Lake Management Society. The three Omaha Lakes Watershed Councils- Walnut Creek Clean Lake Council, Standing Bear Lake Watershed Council and Zorinsky Lake Watershed Council- are working hard to raise the awareness and appreciation for the Omaha metro lakes. They are making a positive impact in their watershed. All three Councils have worked to increase the awareness of the threat of non point source or runoff pollution to Omaha area lakes. Runoff pollution from homes, yards, construction sites, farms, businesses, parking lots and streets, and development sites causes problems in the metro area lakes. Sediment and nutrients are the two major pollutants harming all the metro lakes.

The Standing Bear Lake Watershed Council has marked nearly 500 storm drains with No Dumping messages and distributed runoff pollution prevention educational information to over 1500 residences in the Standing Bear Lake Watershed. The Zorinsky Lake Watershed Council is planning to start a similar effort in their watershed. The Walnut Creek Clean Lake Council provides runoff pollution prevention kits to land developers.

The Douglas/Sarpy Counties Extension Office works with the Councils to provide resources, information and empowerment. Councils are made up of concerned citizens who value and appreciate the metro lakes. To learn more about the lake watershed councils contact the Extension Office at 444-7804.

	Swimmer's Itch Management and Care

Swimmer's Itch, also called cercarial dermatitis, is a skin rash caused by the allergic reaction to infection with certain parasites of birds and mammals. These microscopic parasites are released from infected snails to swim in fresh water, such as lakes and ponds used for swimming and wading. Swimmer's itch is found throughout the world. It generally occurs in the summer months.

The adult parasite lives in the bloodstream of infected host animals such as ducks, geese, gulls, and swans, as well as in certain aquatic mammals such as muskrat and beaver. The parasites produce eggs that are passed in the feces of the host bird or mammals.

If parasite infected feces land in the water, the water becomes contaminated. Snails serve as an intermediary host and then release the cercarial larvae into the water. Humans get Swimmer's Itch when the cercarial larvae burrow into the skin, thus the name cercarial dermatitis. The severe itch and accompanying welting is an allergic reaction to the infection. The larvae cannot develop inside a human and soon die.

There are actions that can be taken to help reduce the odds of getting Swimmer's itch. First, stop feeding ducks and geese at the lake or pond. Secondly, avoid swimming near the shore. Swim from a raft or boat farther out from shore where you are less likely to come into contact with the cercaria. Thirdly, dry off with a towel soon after getting out of the water.

If these strategies fail to solve the problem, a chemical may be applied to the water to kill the snails. The chemical will only kill the snails present at the time of application, any snails which enter the area afterwards will not be affected. The relief provided may be temporary and more than one treatment may be required.

Many factors must be present for Swimmer's Itch to become a problem in lake or pond water. Since these factors change (sometimes within a swim season), Swimmer's Itch will not always be a problem. If swimming pools are well maintained and chlorinated, there is no risk of Swimmer's Itch

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