How can someone provide expert advice on a topic encompassing their self-professed ignorance?
He also gives a statistical answer to the question about the accuracy of the wetlands map. According to Dr. Adamus, the maps have a false positive rate of 3.8% but an unknown false negative rate, implying that it could be quite high. The maps "likely omit" many wetlands, he claims. How many? Only those all-knowing "resident wetland experts" know for sure.
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1. Why does upland habitat need to be
protected?
The WAC does not limit protection
only to wetlands, streams, lakes, and marine habitats. In WAC 365-190-030(6a), FWHCA’s are defined as:
“areas that serve a critical role
in sustaining needed habitats and species for the functional integrity of the
ecosystem, and which, if altered, may reduce the likelihood that the species
will persist over the long term. These areas may include, but are not limited
to, rare or vulnerable ecological systems, communities, and habitat or habitat
elements including seasonal ranges, breeding habitat, winter range, and
movement corridors; and areas with high relative population density or species
richness.”
One scientific reason for
protecting upland habitat is that several wetland-dependent species of
amphibians and birds require both upland habitats and wetland habitats to
complete their life cycle. Under
the Growth Management Act, Counties are required to protect wetland functions. One wetland function that is
specifically mentioned in official guidance is the provision of habitat --
meaning habitat for all species, not just ones listed as threatened or
endangered.
2. Is the forest buffer only necessary to
protect conifers? Why do wetland conifers need to be protected, when there are
so many conifers in upland (non-wetland) area?
No. Forested buffers are needed to protect stands consisting of
any type of wetland tree from excessive blowdown. Trees in wetlands need protection even though there are many
times more trees in uplands, for the simple reason that wetland trees are more
likely to provide essential habitat to animal species that need to live in or
very near wetlands. An example is
wood duck, a species which prefers to nest in (or as close as possible) to
wetlands. Counties are
required to protect the habitat functions of wetlands, and wetland trees are a
major contributor to a wetland’s habitat functions.
3. How accurate is the “Possible Wetlands” map?
As explained in the Wetlands BAS
chapter:
“Of 105 [“possible wetland”] sites
visited, there were four where no evidence (vegetative, soils, or hydrology) of
wetland conditions was found anywhere on the accessible parcel, indicating
either a map error or less likely a recent alteration. In other words, the County’s new map of
“Possible Wetlands” was determined to have a 3.8% commission error.
The rest of the story is that the
maps likely omit many wetlands that could not be detected using only aerial
photos and LiDAR. This is
particularly true of forested wetlands.
Resident wetland experts have confirmed this. However, the omission error rate cannot be measured without
large expenditures of field time.
4. Why should the Mayer paper be used to size
buffers rather than the Zhang paper?
The Zhang et al. used less than one-fifth
of the full spectrum of 45 buffer studies which they might have, either
because they weren't aware of some ("didn't do their homework")
or because they purposely avoided using some. Whereas Mayer et al. have
ferreted out nearly every nitrate buffer study published up to that point, and
objectively included all of them in their analysis. If anything, the
Mayer et al. curve is conservative because it includes a few studies of nitrate
removal by wetlands; wetlands usually remove nitrate more effectively than
upland buffers, although sometimes with detrimental effects to the
wetland. Also, at both the "lower and upper ends of the curve"
for nitrate, Mayer et al. have more data points than Zhang et al. and thus
more credibility to the curve. Most important, the Mayer et al.
publication is not only far more inclusive of published studies, it
also is more transparent and compliant with standard procedures of
academic research and meta-analysis.
Although in theory one could pick
through the studies used in the Zhang or Mayer analysis and analyze only the
studies that had land uses most similar to those in San Juan County, there are
two major problems with doing that:
(1) One cannot assume similarity of
land use (e.g., was it a study in an urban or agricultural setting?) is the
most important driver of how wide a buffer should be. Factors such as buffer slope, soils, size of the
development, and climate are often much more important, so one would have to
determine all of those factors for every study before one could select “just
the studies most relevant to San Juan County situations.”
(2) Doing so would require an
enormous expenditure of time and money, and would prove fruitless in some cases
because many researchers do not report all those background conditions when
they write up their results.
5. With regard to wetlands that don’t have a
surface water outlet – if the soils had high conductivity, with good subsurface
flow out of the wetland, could they be placed in the Low Water Quality/
Sensitivity category?
In theory, probably yes. However, determining if the soils had
high connectivity and good subsurface flow out of the wetland (a) would require
judgment by a qualified professional who visits the wetland at an appropriate
time of year, thus requiring landowners to pay for a consultant, and (b) lacks
any basis for deciding what constitutes “high” connectivity and “good”
subsurface flow.
6. Jon Cain (legal counsel) would like the
definitions of lakeside wetland and large pond wetland refined to be clearer.
I
will need additional guidance as to what is unclear.
“Lakeside
wetland” means a
wetland that is within or contiguous to and within 100 feet of a ponded water
body larger than 20 acres, and whose water levels fluctuate in near synchrony
with those of the water body. This
does not include wetlands that develop on non-wetland sites, as may occur when
water is impounded with a structure.
“Large pond wetland” means a wetland that is within or
contiguous to and within 100 feet of a body of surface water that is between 5
and 20 acres in size and is present for all or most of a normal year; or a
wetland which contains patches of standing water that cover between 5 and 20
acres during all or most of a normal year.
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