-
FEMA FIRM MAP QUESTIONS?
I am researching an elevation project, dwelling is in “Zone X” near “Zone A”.
I have visited the site to look for corner markers and scope out the area of work. The parcel is 34 acres.
I currently have the subdivision map, no house location. I have downloaded PAMAP orthorectifed photos, 2 required to cover parcel and PA LIDAR topography, 2 required also and the FIRM panel map, only 1 required. The house and two outbuildings do not appear on any orthophotos. It does appear on Google Earth, and I have yet to play with it.
First problem is that the FIRM panel to scale and set on PA SPC grid lines does not overlay the PA orthophotos. I had to shift the FIRM about 100′ East and rotate it 2.5å¡ to match images. I have never seen a FIRM so far off. I am very confident in the PA orthophotos, but field checks will be required.
I have to consider doing more than my typical GPS location work, complicated by the dense canopy. It is a considerable distance away so I want to be as effective as possible with my field work plans.
Anyone with any experience with complicated corrections to a FIRM?
I will begin a conversation with FEMA tomorrow as this appears to require more than typical guidance.
I had first thought this would be an eLOMA, maybe it still is.
Paul in PA.
-
2 Replies
-
Paul,
Does this community have DFIRM or NFHL data? S_haz_ar.shp should have the flood boundaries.
DDSM:beer: -
We’ve done a lot of Lomas in our area without the issue you are describing.
Did you try bouncing it off of this site as a back check
http://fema.maps.arcgis.com/home/webmap/viewer.html?webmap=cbe088e7c8704464aa0fc34eb99e7f30
Log in to reply.