Curtain Transects

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Curtain Transects Page
In preparation for a proposed spring 2009 curtain contained (lake within a lake) herbicide treatment several transect profiles were made between the south side of Fox Island and the mainland (rt. 74). These transect profiles were prepared by Rolf Tiedemann, the APA, and Allied Biological, each looked at water depths, distances between possible curtain anchor points, and specific milfoil plant/bed locations to identify the best possible location to put curtains. This transect profile data was collected over several months in the spring of 2009. All of these curtain containment transect proposals were undertaken to establish depth and length of curtains with location proximity to milfoil plants/patches. This bay area was chosen as a result of discussion between APA, Allied Biological, and the Eagle Lake Milfoil Project Coordinator, and the amount of milfoil contained therein. The bay area is about 10 acres with some 2 acres of milfoil ranging from the dense patch highlighted in light green to the many small scattered patches outlined/highlighted with red dots from the 2003 GPS survey.

Additional maps of Eagle Lake can also be found here.

Summary-
All transect/depth and length surveys returned curtains that need to be in the 20-30 foot depth range with total lengths of 900-1000 feet. The only real difference between them was the total area of milfoil that would/could be treated with a selective herbicide.

February 2009' transect survey contained the largest area and encompassed all of the milfoil in this location. It also had the deepest depth of curtains and a 2 piece total length of ~850 feet.
April 2009' transect survey was either in the same locations or moved slightly to seek shallower water. As a result of being in shallower water it cut the densest/largest patch in half (see line 4 in fox island east compiled transect). The total length of the curtain remained ~850 feet.
May 2009' transect survey produced a significantly smaller treatment area, but depth of curtains were still in the 20 foot range and total length of curtain did not change from the previous proposals to stretch curtains off both ends of Fox Island to the mainland. This proposal also require in lake anchor points or extended cables to capture anchorage on shore.

Rough cost analysis proposals were completed for each of the surveys and while each was slightly different all were above and beyond the amount that the project budget could support. More formal reports on costs associated with these and other options are presented here:

2009-3-24 Other options for herbicide use- Plan 1 through 3 options for this area.
2009-4-18 Lake Demonstration Plan- Plan 4 option for the lake.
2009-5-12 reply letter- from APA re. curtains
2009-7-10 Curtain opinion letter- DEC staff Sinott opinion on curtain use in Eagle Lake

Additional information related to these transect surveys and development of the "Spring 2009 Plans" are listed below.

2003 GPS Milfoil Survery Page- Essex County NY: Baseline study documenting the location and size of the largest and densest beds of Eurasian Watermilfoil in Eagle Lake (survey data, maps, and results).
Turbidity Curtains Page- Information related to materials, costs, deployments, and accessories that can be used for creating a lake within a lake.
Curtain Containment Leakage Testing Page- Proposals and materials for determining water exchange rates in curtain contained areas.

Compiled Transects

The transects below are overlay's that combine all of the data collected in the spring of 2009 showing how the transects compare, as ell as the location of milfoil in both 2003 (red dots), 2008 limited and location specific resurvey (purple dots), and blue dots indicate September 2008 Allied Biological Tier III Plant Survey rake toss locations (blue dots).

Fox Island East	Fox Island East 2

For a .pdf version of this map click here.	For a .pdf version of this map click here.
Ruck's Bay	Transect Survey Locations

For a .pdf version of this map click here.	For a .pdf version of this map click here.

May 2009 Survey

This survey was conducted by Allied Biological and produced the map below as their proposed curtain containment method on the east end of Fox Island. This was completed in an attempt to shrink both the cost and size of the treatment area to bring costs into an affordable range. This curtain was also intended to be anchored to the bottom instead of relying on shore anchor points.

Fox Island East

For a .pdf version of this map click here.

April 2009 Survey

This survey was conducted by the Adirondack Park Agency and produced the map and data table below. It included a resurvey of the February 2009 transect to prove the accuracy of the actual depths of 30' that were reported originally. Depths were confirmed to be accurate. It also looked at moving the February 2009 transects to differing locations in a hope of finding shallower crossing locations to reduce curtain expense. These alternative locations for putting curtains placed them over or through the middle of dense milfoil beds. These measurements were gathered by Ed Snezik (APA) and Tyler Smith (APIPP), with the assistance of Rolf Tiedemann (ELPOI Project Coordinator) with a depth sounder in a boat after the ice went out. Milfoil was not visible at this time due to early season and poor weather conditions on the date of survey.

Containment Options	Depth Profile

For a .pdf version of this map click here.	For a .pdf version of this data click here.
Fall 2009 Addendum- Milfoil located behind "Curtain 5" (top center of image) 2003 survey patch #22 was hand picked and matted as part of the summer 2009 work sites. Approximately 1250 square feet of mats were placed and 1-2 bags of milfoil were removed.

February 2009 Surveys

This data was the first true length and depth measurement gathered for this area. It was assumed in the discussion to select this area that depths would be in the 10-15 foot range and lengths in the 300-350 foot range on both sides of the island. The data was collected by referencing the 2003 Milfoil Baseline Study to indicate where the edges of the patches were located. Yellow points indicate measurement locations. Numbers in blue indicate actual depth (in feet) taken through the ice with a string and weight while the lake was at plus 4. Information gathered and compiled by Rolf and Michael Tiedemann.

Images of the survey being conducted are available for viewing through our photo page here.

Fox Island West	Fox Island East

For a .pdf version of this map click here.	For a .pdf version of this map click here.
Fox Island Overview	Transect Survey Locations

For a .pdf version of this map click here.	For a .pdf version of this map click here.