how can a lake have an affect on the community?

Do you mean "have an effect"?

Of course, they can. Just ask residents in Chicago, Cleveland, and Toronto!

Here's an example:
http://www.google.com/?gws_rd=ssl#q=lake+effect+snow

They can make money through tourism - if it's a particularly scenic lake.

They can also make money if there are fish present in the lake. People can be charged for fishing in the lake or the people of the community can fish for a living.

A lake, even a small one, has recreational opportunities: boating, water skiing, swimming, as well as fishing. The Great Lakes and other large lakes also provide water transportation (shipping).

Having lived most of my life within 40 miles of Lake Michigan, I know it moderates the temperatures and also produces lake-effect snow.

Weather is affected by very large lakes like the Great Lakes, but not so much by smaller ones, even Tahoe or Champlain don't affect the weather as much, and certainly not Lake Springfield (man-made) or Cedar Lake at Marcellus. I hope this brainstorming is helpful to our student here!

A lake can have a significant impact on the surrounding community in several ways. Here are some key ways a lake can affect a community:

1. Recreation and Tourism: Lakes often serve as popular destinations for recreational activities like boating, fishing, swimming, and picnicking. They attract tourists, which can boost the local economy through visitor spending on accommodations, food, and other services.

2. Economic Development: Lakes can provide opportunities for local businesses, such as marinas, boat rentals, tour operators, restaurants, and souvenir shops. These establishments create jobs, generate revenue, and stimulate economic growth in the community.

3. Ecology and Biodiversity: Lakes support a wide variety of plant and animal species, contributing to local biodiversity. They provide habitats for aquatic plants, fish, birds, and other wildlife. This ecological richness enhances environmental quality and can attract nature enthusiasts.

4. Water Supply and Irrigation: Lakes often serve as a vital source of freshwater for the community, supplying drinking water for residential, industrial, and agricultural needs. They may also help in irrigation, supporting agriculture and local food production.

5. Flood Control: Lakes can play a role in flood management by acting as catchment areas, regulating water flow, and storage during heavy rainfall. They can mitigate the risk of flooding and safeguard the community's infrastructure and properties.

To understand the specific impact of a lake on a community, it is recommended to gather more detailed information about the particular lake, its features, location, and interactions with the surrounding area. Consulting local authorities, community organizations, environmental agencies, or conducting studies can help in assessing the specific effects of a lake on a community.