This is caused by an excess of nutrients in the water and is called eutrophication. For an overview see:

http://en.wikipedia.org/wiki/Eutrophication

The green scum is an algal bloom that results from the high nutrient levels and can cause numerous problems ranging from visual ugliness and bad smells to harmful toxins in the water. Hop Brook and its associated ponds are one of several examples in the Town of Sudbury. Some species of blue-green algae (cyanobacteria) release harmful toxins into the water. Other species are benign or even beneficial. An overview of cyanobacteria is at:

http://en.wikipedia.org/wiki/Cyanobacteria

The World Health Organization has produced very detailed information on toxic cyanobacteria in water at:

http://www.who.int/water_sanitation_health/resourcesquality/toxicyanbact/en/

Additional (very technical) information can be found in the following USEPA report:

http://www.epa.gov/OGWDW/ucmr/pdfs/meeting_ucmr1_may2001.pdf

Remediation of eutrophication in the ponds and waterways in Sudbury is a complex issue facing the Town of Sudbury as well as other towns and our State and Federal governments.

A soil test can be a valuable tool in assessing your lawn's nutritional balance and as an aid to protecting the environment and saving money by applying only the amount of fertilizer needed. For more information, visit the UMASS Extension website at: http://www.umass.edu/soiltest/.

Dealing with problems caused by beavers is controlled by state law. The following site gives detailed explanations of the options available and the procedures that must be followed. It is important to understand both the beavers and the law before proceeding with any action.

http://www.mass.gov/dfwele/dfw/wildlife/facts/mammals/beaver/beaver_conflicts.htm

Any alteration of land bordering waters is regulated by state law. A well defined procedure must be followed before any action is taken. The law can be found at:

http://www.mass.gov/legis/laws/mgl/131-40.htm

For more information or to initiate the permit process, contact the Sudbury Conservation Commission. The Conservation Commission website can be found at:

http://www.town.sudbury.ma.us/committees/committee_home.asp?dept=ConservationCommission

Here are some links to helpful tips:

• Quick summary: http://www.stormwatermatters.org/lawn.html
• Verbose details: http://www.richsoil.com/lawn-care.jsp

Cutting, Frost Farm, Goodnow, Great Meadows, Nobscot, Pelham Island, Powder Mill, Wayside, Woodside

This is an aquatic weed harvester owned by the Great Meadows

National Wildlife Refuge used to help combat invasive aquatic plants on the Sudbury River. The harvester has also been generously loaned to neighboring towns such as Sudbury. Information on other usage in Sudbury as well as considerable information on invasive aquatic plants can be found on the Hop Brook Protection Association site at:

http://www.hopbrook.org/id19.htm

The State of Massachusetts recognizes invasives as a widespread problem with more information at:

http://www.mass.gov/dcr/waterSupply/lakepond/invasive_1.htm

The USDA also provides a reference site:

http://www.invasivespeciesinfo.gov/aquatics/main.shtml

Many communities across the country are having to come up with ways to approach this problem and learn from each other. The Water Chestnut is among the most notorious problems in the northeast. The Management Plan for Chesapeake Bay in Maryland is an excellent point of reference and history:

http://www.anstaskforce.gov/Species%20plans/Water%20Chestnut%20Mgt%20Plan.pdf