Truesdale Lake  

South Salem, New York

Lake Health


“Treat the Earth well. It was not given to you by your parents;  it was loaned to you by your children.”

-Ecologist Lee Talbot

What you can do

Good stewardship by the individual, whether a lake homeowner or simply a lake user, can do much to enhance  the lake environment and serve as a beginning for sound lake management. Although most of the following comments are directed to lake homeowners, many also apply to those who live anywhere within a lake’s watershed.  Your collective efforts will yield the greatest dividends for you and the lake. Here’s what you can do to protect and improve a lake by minimizing polluted runoff.

1. Plan Wisely Before Building

  • The location of a house or cabin and septic system can negatively affect the lake if not sited properly. Minimize any impacts by following these guidelines.
  • Don’t let the house intrude upon the lake. Position a new house and any future additions to meet horizontal setbacks and vertical elevation requirements and to avoid damage if the lake rises dramatically in the future.
  • Preserve as much natural vegetation as possible between the house and the lake to filter sediments and nutrients from surface runoff.
  • Consider other facilities, particularly wells and septic systems, when siting the house. The septic system should receive priority since adequate soil conditions are necessary for its proper functioning. Site evaluators and many sewage system installers can conduct soil borings and percolation tests and consult soil maps and data to determine the best location on the lot. Wells should be located upslope from sewage systems and be deep and cased whenever possible. A site sketch of the lot, drawn to scale, will help to decide the best locations for all facilities and is often required when obtaining permits.
  • Make sure the contractors know which trees should be saved. Fence off areas to protect trees and roots from construction damage.
  • Don’t place a road or wide path down to the lake.  This creates a direct route for runoff.  Make the path narrow and curvilinear. If access along a steep slope is needed, consider a wooden stairway rather than a path. This will help reduce runoff to the lake.

2. Create a Buffer Zone

To protect the lake, minimize any changes to the natural waterfront.

  • Think twice before putting in a lawn down to the lake.  A short turf may will attract nuisance geese. Determine how much area is really needed for recreation. For example, on a 100 foot lot, maybe a 25 foot wide strip of lawn for access to the dock and swimming area would be adequate. Leave the rest in natural vegetation.
  • Plant native grasses. For areas with no buffer zone, replant with native grasses*, wildflowers, trees, and shrubs. These plants take up nutrients for their own metabolism reducing the amount of nutrients entering the lake. The buffer should be a minimum of 15 feet wide and preferably 25 feet wide around the lake to protect the shoreline and filter pollution. Turf environments should grade into coarse grass buffers and then to shrubs for maximum effectiveness.

3. Modify Yard Care

Lake Minnetonka Comics

Lake Minnetonka Comics

The fertilizers you put on your lawn also fertilize the weeds in the lake. Whether the property is on the water or not, we are all on the Lake Truesdale watershed.  There are many simple practices homeowners can do to reduce pollution to their watershed and ultimately to the Lake.

  • Minimize the amount of turf.  Plant more of the yard in native grasses, wildflowers, shrubs, and trees.
  • Replace your turf lawn with hardy drought resistant grass mixtures.  A resistant grass mixture will stand up to more pests and disease, requiring less pesticides and fertilization. Lawns that require frequent watering often lose the fertilizer’s nutrients into the lake and streams.  Also consider avoiding Kentucky bluegrass and perennial ryegrass which attracts waterfowl because they find it particularly tasty.
  • Minimize the use of pesticides, herbicides, and fertilizers, which can harm the lake. Typically lawn fertilizers are water-soluble and their use should be minimized near open water. Soil samples** can be analyzed to determine if phosphorus is needed and if not needed, no more phosphorus should be applied.  (Update: Westchester County law prohibits the use of Phosphorus fertilizer as of May 2009.) One pound of phosphorus can grow up to 500 lbs of plants or algae.  A 50 Lb. bag of commercial lawn fertilizer contains  between 2 1/2 and 7 1/2 lbs. of phosphorous.
  • At a minimum, insure that only enough (non-phosphorus) fertilizer is applied to meet the needs of the lawn and plantings. Discontinue fertilizer applications to trees, shrubs, flowerbeds, and turf grass in areas that drain to the lake. Applications of fertilizer should never be done immediately preceding heavy rain and only organic slow release fertilizers should be used when available. Fertilizer should never be applied more than once per year.
  • Cut turf grass at a height of 2 1/2 – 3”. Aerate the lawn to promote infiltration. Use a mulching lawn mower to return grass clippings to the lawn and reduce the amount of fertilizer needed.
  • Use a broom to sweep up the driveway rather than hosing it down to the storm sewers.
  • Don’t burn brush or leaves on a slope from which ashes can wash into the lake.
  • Keep leaves, twigs and grass clippings out of the lake.  TLPOA provides leaf & twig pickup every fall to prevent them from being carried into the lake where they decompose and use oxygen.  Please take advantage.

4. Taking Care of Your Septic System

It is critical for the health of our lake that we exercise care when we choose detergents and other chemicals that could find their way into Lake Truesdale. Diligent maintenance of our septic systems will prevent nutrients and bacteria from entering the lake.  Even a properly operating septic system isn’t entirely efficient in removing pollutants from waste. Inadequate treatment of wastewater may be a risk to human and animal health. Untreated wastewater contains viruses, bacteria, and other disease causing pathogens that can enter ground or surface water and make drinking water or beaches unfit for use.  Improve the treatment of wastewater from the home by taking the following actions:

  • Consider an alternative wastewater treatment system such as a composting toilet, gray water system, or holding tank. These systems do not pollute the soil or groundwater and should be considered for new or upgraded construction adjacent to surface waters or in areas with high water tables.
  • Don’t let the septic system pollute the lake. Proper maintenance is vital to keep the system working properly. Have the septic tank checked every two years and pumped when necessary, at least every three years.
  • Replace failing septic systems or those that are not in compliance with current rules.
  • Use non-phosphate products.  Wash only full loads of clothes, and use water-saving showers and toilets to avoid stressing the septic system.  Watch out for phosphates in soaps, water-softening products and dishwashing detergents.
  • Do not use a garbage disposal, and keep solvents, plastics, paper, diapers, and other similar products out of your septic system. These may harm the septic system or plug the drain field. Use only minimal amounts of mild drain cleaners and cleansers.
  • Don’t use septic system additives. They are not needed and may do more harm than good.

5. Reduce Runoff from the Yard

Reducing the amount of water leaving the property reduces the pollutant load reaching the lake. Here are some ways to reduce runoff:

  • Limit the amount of impervious areas such as driveways, sidewalks, patios, and plastic under landscape rock so that water can soak into the ground rather than run off.  Asphalt driveways should be avoided, particularly those running straight into the lake.  Using alternative, more porous materials are ideal.  At the very least, diverting water and creating buffer zones can be a huge help.
  • Grade areas and direct runoff so it spreads into a larger area rather than flowing in a concentrated stream.
  • Direct downspouts onto a grass or planted area rather than the driveway or sidewalk.
  • Have the lawn aerated regularly to reduce compaction of the soils and improve infiltration.
  • Install rain gardens or rain barrels to collect water that would normally run off into the street.
  • Replace lawn with long, fibrous-rooted, native plants to promote infiltration and transpiration of water.
  • Direct drainage from the sump pump to a vegetated area where it can infiltrate.

6) Discourage water birds

Since waterfowl can contribute significant phosphorus to the lake, do everything you can to discourage them from visiting the lake and the surrounding lawns:

  • Do not feed geese, ducks, or other wildlife. Bread is waterfowl’s equivalent of human “junk food”.
  • Consumption of their natural diet – insects and plants – helps keep surface water clean.  Large flocks of birds also create large amounts of waste and serious water pollution problems. Not only is excess excrement a nuisance, it encourages anaerobic conditions as decomposition consumes more oxygen than is readily available from water. This leads to unsightly water and unpleasant odors.
  • Create that buffer zone.  Geese in particular will usually not cross a buffer to feed on lawns as they are reluctant to walk through vegetation taller than they, for fear of predators.
  • Use visual deterrents. Mylar tape that flashes in the sunlight and hums in wind is known to repel birds. String the tape at the water’s edge. Leave some slack and twist it as you string it from stake to stake.
  • Install low wires or fencing along the water front. This will be an effective deterrent during summer molt.
  • Pick up after your pet.  For the same reason birds are discouraged, keep the shoreline and storm drains free of pet waste.  Since all storm drains in our neighborhood lead to the lake, please use plastic bags and scoopers at all times around Lake Truesdale.

7. Modify Boating, Swimming, and Fishing Practices

Our lake is a wonderful recreational area. Help keep it safe by following these practices:

  • Replace your lead sinkers and tackle with non-lead alternatives. The lead is toxic to loons and other waterfowl that ingest it when feeding.
  • When entering or leaving a lake, check the boat, trailer, anchor, and bait buckets for exotic species such as Zebra Mussels or Eurasian Water Milfoil. Notify the local natural resources department if a questionable species is found. We have been lucky that our lake has not seen exotic species.  If possible, keep your boat only in Truesdale Lake.  If using a boat that has previously been in another body of water, steam cleaning your boat is highly recommended (DEP provides this service) to kill any organisms and substances that might otherwise dominate the ecosystem or contaminate the water supply.
  • At the very least, hose off the entire outside of the boat, and leave it exposed hull side up to the sun for 48 hours to kill any animals that may be hitchhiking. Inspect it carefully to ensure there are no plant fragments.  Invasive plants such as milfoil only require a small portion of the plant to propagate.
  • Don’t use the lake for trash. Although this may seem obvious, even seemingly safe items shouldn’t be thrown into the lake.  For example, common aquarium plants sold in pet stores shouldn’t be thrown near or into the lake because they are potentially invasive if released into the wild.  Throw them into the garbage instead.
  • Don’t use the lake as a toilet. This applies to swimming, ice fishing as well as open water fishing.
  • Don’t use the lake as a bathtub. Soaps and shampoos contain nutrients and pollutants that are harmful to the lake and animal species. Wash and rinse on the land, not in the lake.
This text largely taken from the Minnesota Pollution Contol Agency’s “Guide to Lake Protection & Management” at
Information supported and augmented by Land-Tech Consultants’ “Lake Evaluation Study” of Lake Truesdale, Sept 2001, at
Discouraging water birds section taken from the Truesdale Lake Management Committee: Animal Waste and Water Quality – at
* List of native plants and planting information by Allied Biological, the company hired to manage our lake treatments, is at
** Cornell provides analysis and recommendations on soil samples for under $20.  Go to
This document was originally compiled by Wendy McLean in March 2006.