June 25, 2015 – Dredge Site Vegetation Update

Dredge and Rainey Report
Dredge Site Vegetation Update

June 25, 2015

The small dredge has been idle since August 2013. We stopped dredging after filling Cell 3 and completing an acre so that the LSU graduate could conduct monitoring research unimpeded.

On June 25, 2015, I had an opportunity to go up in an Ultralight plane that was doing work around the Sanctuary and took some aerial photography of the dredge area. I knew the marsh vegetation was filling in rapidly and taking photos from the ground was becoming laughable – the grass is taller than I am! Aerial photography showed what I could not see past the grass at the walkway – it is quickly filling in and becoming solid marsh.

Figure 1 shows the original pond and the layout for containment. We filled cells 5, 4 and 3. Figures 1-3 are photographs of the same area taken on June 25, 2015 from different directions. Figure 4 is the graphical depiction showing fill elevations and new vegetation.

Figure 1. This shows the original pond and layout of cells and containment (orange lines). We filled Cell 5 first in 2010, Cell 4 in 2012 and Cell 3 in 2013. Cells 1 and 2 received overflow material.

Figure 2. Oblique photograph taken June 25, 2015 with the eastern part of Cell 5 clipped.

Figure 3. Oblique photograph taken June 25, 2015 with the view to the west.

Figure 4. Oblique photograph taken June 25, 2015 with the view to the south. Cell 5 is to the upper left; cell 4 is the green area upper center; Cell 3 is center-left and left of the walkway.

Figure 5. This is the estimated status of the cells on June 25, 2015, showing that the marsh grass has almost completely filled in the filled cells. The boardwalk is shown as a bold yellow line, walkways are thin yellow lines, white dots are pvc marker poles, grey are containment structures, and bright green is the extent of new vegetation.



Karen A Westphal and Timmy J Vincent, National Audubon Society
Audubon Louisiana and the Paul J Rainey Wildlife Refuge
6160 Perkins Road, Suite 215, Baton Rouge, LA 70808
225-768-0921x202 office, kwestphal@audubon.org
This entry was posted in Dredge Reports. Bookmark the permalink.