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Re: E-M:/ Wetland mapping myth

As a wetland consultant in my spare time, I basically agree with "anhinga" regarding the value of wetland inventories, the usefulness of the various maps, and detriments to relying to any great extent on an inventory for regulatory determinations.
I checked with the DEQ before the public hearings on these inventories, and they confirmed that they were produced largely to fulfill the apparent statutory requirement in Part 303. The maps are not intended as a final jurisdictional determination or even identification of wetland/upland. They are more like a general notice to landowners that have wetland mapped on their property, that they very likely will have a wetland "issue" sometime in the future if they choose to make use of their land.
One very positive aspect to these maps, as it was explained to me by DEQ, is that they allow the DEQ to take jurisdiction over wetlands that are not contiguous, but greater than 5 acres in counties with less than 100,000 population.
Why this last round of particular wetland maps just happened to be completed during the waning hours of the Engler administration, and what advantage there might be to that, I don't know. My understanding is that the latest inventories covered only about 7-8 counties, and prior to these, only a few counties have been completed. So, most of the State remains to be inventoried, or the maps completed. Based on my phone calls over the last few years inquiring about digital soil data for particular counties, my understanding is that much of it is not yet completed by USDA, and those counties that have been completed apparently include the counties for which wetland inventories were just issued. Essentially, these inventories have existed for roughly 15 years, but as 3 separate maps, NWI, MIRIS, and soil surveys. The soil surveys are the oldest, generally, but least specific to wetlands, but are very good indicators of what conditions may be present. Given all the budget cuts on both federal and state levels that have eliminated important environmental programs, I guess it's not hard to see how it took so long to put these 3 maps together. Anyone who has tried just to get a hard copy of a county soil survey has probably encountered the pathetic underfunding of this important reference.
Eventually, I think a more accurate inventory of wetlands and other significant natural features can and should be produced, but used as a permanent protection effort rather than just a regulatory program. The current inventories can at least be used to designate critical wetlands for protection through acquisition and other means.
Bill Collins
Huron Ecologic, LLC
3335 Crooks Road
Rochester Hills, Michigan 48309 USA
phone & fax: 248-852-4682
e-mail: huronecologic@netzero.net
Huron Ecologic provides wetland delineations, wetland permitting, wetland mitigation design & monitoring, tree inventories, botanical & ecological surveys, natural area protection, nature education, and technical training.
-----Original Message-----
From: "anhinga" <anhinga@tm.net>
To: "enviro-mich" <enviro-mich@great-lakes.net>
Subject: E-M:/ Wetland mapping myth
Date: Thu, 5 Dec 2002 19:40:06 -0500
I believe there is much misunderstanding about the nature and value of wetland inventories and mapping.  The concept of complete and accurate wetland maps is wonderful; the liklihood of ever achieving that ideal is very remote.  I have delineated wetlands, on the ground, for many years and have compared wetland maps to reality and been very disappointed.  To create statewide wetland maps that are reliable - and anything less is a waste of time - will require a large army of well-trained people with very accurate GPSs and several decades to do their work.  (How long have we been working on soil surveys?  Wetland delineations are much finer work.)  I would love to be part of that army, but I don't have anything strong enough to put in my hookah that could make me believe any government is willing to make such a commitment.
The wetland maps that have recently been produced by the DEQ are amalgamations of the information already available in county soil surveys, National Wetland Inventory maps, and the old DNR MIRIS maps.  Soil surveys are notoriously inconsistent from county to county and at their very best have a spatial resolution of about 2 acres.  MIRIS wetland maps are junk.  The NWI maps are the most accurate, are not the result of on-site delineations, and are 1:24,000 gross generalizations of wetland occurance.  An area mapped as wetland typically has a fairly high probability of being wetland, but areas not mapped as wetland are terra incognita.
Part 303, Wetlands Protection would be  better law if all reference to wetland inventories - for locals and the state - were struck.  Read the last three sentences of section 30308 and you will understand the problem with inventories as they are actually performed: you can not rely on the information in them, they have no absolute authority, and are therefore open to challenge in every instance.  So where does that leave us?  Back to site by site analysis of wetland resources, right where we are now. 
My belief is that many of the people who are pushing for completion of an inventory know that many wetlands will be unaccounted for, that any upland mapped as wetland can easily be taken out of the inventory by challenge, that an inventory will replace ground truth, and that the inventory will ultimately result in a more comfortable climate for developers.  I see an inventory replacing people who have wetland expertise.