Hi Julie, 

Thanks for reaching out to MSU Extension. There are a variety of ways to manage ponds and the aquatic plants that tend to grow in them. If a waterbody receives a large amount of runoff that contains excessive nutrients (such as phosphorus from lawn fertilizer) -- a larger amount of aquatic plants/algae tend to grow. Every community manages aquatic plants in ponds/lakes differently. Some choose to apply chemicals to treat the plants while other let nature takes it course. I will note that aquatic plants for the most part are an important part of the ecosystem. 

I'm going to share a few resources with you about ponds, aquatic plants, and managing runoff that you may find valuable to review and share with others in your community. 

Our friends at Purdue Extension have a great pond website with information on managing plants and a variety of other information. Learn more here: https://extension.purdue.edu/pondwildlife/pond.html. You can download a PDF on managing aquatic plants from their website for free. 

The MSU Extension Smart Gardening program has a variety of resources regarding water quality including managing stormwater and fertilizer applications for lawn care. These factsheets can be shared with your neighbors. 

It is important to note that permits from the Michigan Dept. of Environment, Great Lakes, and Energy (EGLE) are required for aquatic herbicide application. Learn more on the Aquatic Nuisance Control website: https://www.michigan.gov/egle/about/organization/water-resources/aquatic-nuisance-control

This guidebook from EGLE is also fairly informative regarding aquatic plants and their role in the ecosystem. 

Thanks for reaching out to Extension. I hope you find these resources helpful.