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  • chevron_rightWhat's the water temperature?
  • chevron_rightEurasian Milfoil
    Eurasian Milfoil
    If you haven’t noticed – It’s Back!
       We’ve had a good ride, for about 20 years since 1994, when triploid grass carp were introduced to Lake Mahopac, to consume an invasive aquatic plant species. Eurasian Milfoil is making a comeback, it was noticed as of late last summer. The Lake Mahopac Park District has been in contact with the New York State Dept. of Environmental Conservation (NYSDEC,) since last September concerning this issue. Triploid carp are vegetarians and do not eat fish also, they are sterile and cannot reproduce.
     There are three (3) ways to deal with milfoil; mechanical, chemical and biological.
    Mechanical, such as a weed harvester was tried for several years; it was expensive; for the machinery and personnel, noisy and ineffective for a 583.4 acre lake. Chemical is too expensive for a lake this size and Lake Mahopac is a domestic water supply for many residents; those two reasons are why we ruled it out. Biological, in the form of grass carp, was the preferred choice.
    The NYSDEC has agreed to come out and survey the lake in mid July to assess the extent of the weed coverage and give a better estimate of how many triploid carp are needed to control the milfoil. Once we get this information we can be permitted to restock the carp. More on this later.
  • chevron_rightReporting Violations
    Please report any violations to:
    • Dept. of Environmental Protection    (914)245-6694
    • Town of Carmel Police Dept.  (845)628-1300
  • chevron_rightGeese Management
    Geese Management
    The efforts to control the Canadian Geese population on the lake continued this year with the help of Jim Maxwell and a team of volunteers. Egg addling expeditions are held in the spring on the islands and lake shore. Many surrounding lakes and reservoirs also have the issue of too may geese but so far, through the efforts of our committed team, we have been able to stay ahead of the goose population. This is a continuing task and everyone’s help is requested. Please report any goose nest that has been missed to the committee via the website Contact US Page.
  • chevron_rightLake Permits
    Some examples of activities requiring a permit are:
    • installation of a floating dock or dock constructed on piles;
    • establishment of a marina consisting of multiple docks and ramps, breakwaters and other in-water structures;
    • installation of a platform to accommodate a use or activity on or above the water (i.e., deck, boathouse);
    • restoring or rebuilding an existing dock, pier, or wharf;
    • substantially changing the use of an existing dock or platform;
    • the installation of mooring devices
    Do I need a permit
    NYS DEC Floating object permit for Moorings, swim platform, docks
    Protection of Waters: Construction, Reconstruction or Expansion of Docking and Mooring Facilities.
  • chevron_rightHow's the Water?
    This is the thirteenth year since the grass carp have been introduced (October 1994) into Lake Mahopac for controlling the Eurasian Milfoil population, and the ninth year the Louis Calder Center performed both the water quality monitoring and vegetation study for Lake Mahopac.  The sampling was conducted on August 4, 2006 at the same sites of the previous years.  The report on this years sampling is expected shortly.
    The grass carp are continuing to keep the Eurasion Milfoil from reestablishing itself at the annual sampling sites; however as in the previous year there have been sightings of milfoil in the lake by some residents.  This is the third year that another plant, Wild Celery, has also been seen in some of the coves around the lake.  This plant is a native (non-invasive) to Lake Mahopac and should not been considered a threat to the lake’s ecosystem.  Aquatic vegetation is a source of (1) food for fish and small insects, (2) protection for breeding fish and (3) oxygen.  A moderate population of aquatic plants (20 to 30%) is essential for the long-term health of the lake.
    Water temperature was warmer and oxygen lower this year as compared to last year.  This is the second year that oxygen levels were lower.   Oxygen levels are affected by (1) temperature (warmer water equals less oxygen) or (2) consumption of oxygen by fish and bacteria is greater than production of oxygen by plants and algae.  Additionally, nitrogen levels were higher near the bottom of the lake where nutrient loading under low oxygen levels is greatest.
    In summary, the grass carp are still keeping the Eurasion Milfoil from dominating in the lake and the water quality of Lake Mahopac is good.
  • chevron_rightLake Friendly Fertilizer; Now available!
    Lake Friendly Fertilizer; Now available!
    In a previous newsletter there was an article titled, "Feed Your Lawn; Not The Lake." The subject of the article was the negative impact that phosphorous has on fresh water lakes. Phosphorous is the "limiting factor," which can be interpreted as the growth factor for aquatic vegetation in fresh water, (nitrogen is the limiting factor in salt water bodies.) If you do lawn maintenance yourself or employ a lawn maintenance company, you need to have a discussion with them about the non-necessity phosphorous applications on established lawns. Many of these companies are well aware of the problem and are happy to comply.
     The excess introduction of phosphorous through fertilizer encourages aquatic plant growth in the lake. Nitrogen is what makes the lawn look nice and green. Phosphorous is not needed in an established lawn. (New lawns may require phosphorous to initially set up a good root system, a soil test will  indicate if phosphorous is needed. The Cornell Cooperative Extension provides inexpensive soil testing for phosphorous level and soil typing. The cost is a mere $10, and takes a days time,  just bring in a cup of soil. For $15, a soil test kit is available for  a much more extensive testing of soil parameters. To contact the Extension, which is located above the Motor Vehicle Dept. in Brewster, call 845-278-6738 for further information.
             There are three (3) numbers on a bag of fertilizer: the first indicates Nitrogen, the second indicates Phosphorous and the third, is Potash. Lesco, a major manufacturer, makes a lawn fertilizer product with a 24-0-12 designation meaning no phosphorous. It is sold at their distribution center at 2 John Walsh Blvd., Peekskill, NY. A 50 lb. bag costs $17.75 and it covers 12,000 sq. ft. Their phone # is 914-736-9056. Your lake will thank you.
    You can help by:  
    • Eliminate using fertilizer containing phosphorus
    • Use only slow release or organic fertilizers .
    • Clean up any fertilizer that gets on pavement areas where it may wash off into the lake.
    • Water after fertilizing but do not over water.
    • Always read the fertilizer cautionary labels. Some are not recommended to be used near water.
    • Have your soil tested and follow soil test recommendations on the correct fertilizer blend.
    • Leave a strip of unmanaged grasses or natural vegetation around the shoreline as a buffer zone.
    • Another method is to construct and maintain a modified "berm" along the shoreline. This is best described as a slight hump in the ground that would  run near and parallel to the shoreline. This rise in the ground/lawn will serve as an obstacle to the rapid and direct nutrient-rich runoff into the lake.
    Other interesting links about runoff, Fertilizers and Pesticides:
  • chevron_rightDraw-down as a Lake Management Tool
    Draw-down as a Lake  Management Tool
    The lake draw down commences with the opening of the sluice in late October or early November depending on water Temperature. The sluice gate is closed in mid-February and the lake returned to its normal level by mid May. In general, the amount of precipitation an area will receive each year can be quite predictable; however, there are always exceptions to the general rule. The Lake Advisory Board monitors the prevalent weather patterns and the affect it has on the lake level.  The plan at this time is to repeat the draw down schedule activity in a similar manner this coming fall. The benefits of a draw down are many. such as the reduction of ice damage to lake shore structure such as seawalls, docks and boat houses. Reason for water temperature monitoring is to avoid releasing Zebra mussel larvae into Amawalk reservoir. 
  • chevron_rightFlotsam & Jetsam
    Flotsam & Jetsam
    Flotsam and jetsam are 18th century terms used to refer to debris in the ocean. Technically, flotsam referred to materials that unintentionally end up in the sea as a result of a shipwreck. Jetsam referred to materials and goods that a crew would purposely throw overboard in an attempt to lighten the ship during an emergency.
    In the modern day, flotsam and jetsam can also be found in Lake Mahopac. Some of the debris in the lake is a result of the winter freeze  “liberating” docks and lumber from the shoreline. Natural materials such as trees and branches also wind up in the water as the result of the winter storms. It’s a good idea to keep a keen eye out for these hazards when boating in the early spring.
    Last summer the lake committee oversaw the removal of a large willow tree that had drifted into the west cove and become lodged in mud, posing a hazard to swimmers, skiers and boaters. With the help of the Coast Guard Auxiliary and the Carmel Town Highway Department, the 65’ willow was towed to the Mahopac Beach Restaurant parking lot and removed from the lake. Our thanks to property owner Mike Barile for permitting the use of the restaurant parking lot for the operation.
    Early this June, new pressure treated lumber escaped from a dock construction sight as a result of a sudden afternoon storm. These substantial planks were removed before any serious damage resulted.
    Whether intentional or not, materials do find their way into the lake’s water. We encourage everyone to do their part in removing trash, bottles, cans, tree limbs or whatever is found. Inform the Carmel Police (845-628-1300) of any large items that represent a safety hazard. Thanks in advance for doing your part to keep our lake safe and clean.
  • chevron_rightHow does one become a Lake Mahopac Park District Advisory board member?
    They are appointed by the Town Board yearly.  Only 5 board members. Required to be a part of the Lake Mahopac Park TAX DISTRICT (own Lake Front Property). 
  • chevron_rightHow can I get meeting minutes?
    Must be formal written request to the town.
  • chevron_rightWho does the Lake Mahopac Parks District represent?
    We represent the Lake Mahopac Park District tax base who are the lake front property owners.  Non owners of lake front that use the lake don't bare the cost but still get the rewards that the lake front owners are taxed with to keep the lake heathy and safe.