So the DNR says I can’t build my deep winter greenhouse where I want it, because they say it is too close to wetlands. I can put a trailer or portable unit there though. So I am building two 8 by 16 foot “halves “ that I can haul out to my land on a trailer and put them together there. Got the base done on the insulated half and am starting to put the roof trusses up. I am using a recycled styrofoam and Portland cement mix for my insulation on the floor, walls and roof. More later.
GC
Interesting build Garry.
Are you going to park it in a trench to get a little of the benefits of a dug down greenhouse to try to keep it warmer and out of the wind or is it too much of a wetland?
No, on a hill next to the wetlands that has big trees on the east, west and north sides. The floor has 7” of styrofoam/cement insulation that has an R factor of about 3.2 per inch.
GC
Garry, Is the wetlands located within a DNR Flood Plain?
If “Yes” Then is the proposed location of your winter Greenhouse in the Flood Plain too?
If “Yes” Then you need to locate your Greenhouse a minimum of 2 feet above the 100 year flood plain elevation, or as needed to comply with local, state, or federal codes.
If “No”, Then will you be able to move the Greenhouse?
If “Yes” Make sure when it rains you have temporarily located your Greenhouse at a point that the rain water runoff will not flow into the wetlands. This may be a “red flag” for DNR? If you can prove you will only be using organic products, this may not be a concern? DNR will not approve a possible scenario where there is a chance for chemicals from your Greenhouse to wash or drain down and into the Wetlands. This could be the same as locating your outdoor garden uphill from a wetlands, one of the reasons why is that exposed soil in a garden may erode and transport small particles of chemicals used in the garden down stream and into a waterway…
Other considerations would be for example, if you mix and pour concrete uphill from the wetlands, and washout (concrete slurry) from the pour ends up in the wetlands, then when DNR discovers this they will come back on the owner and make them clean up any contaminated areas, which can be very costly.
Do not get me wrong, there are ways that may be approved for new construction above a wetlands, but an “Erosion And Sediment Control Plan” will need to first be submitted and approved by DNR and or all other entities that may have jurisdiction over this area.
It is my experience that the words “New Construction” and “Wetlands” never mesh “easy” if at all.
I retired as my communities Stormwater Superintendent, MS4 Coordinator, and was a Certified Inspector of Sediment and Erosion Control.
Hope this helps, and all areas may fall under different requirements for local, state, and or federal compliance as relating to EPA’s “Clean Water Act (CWA)”
G_Dub
Thanks for all your good advice. Yes the greenhouse is more than 2 feet above the floodplain. The problem with building a permanent structure is that it is too close to the wetlands even though it is way higher. Yes the greenhouse is portable and can be moved. No concrete will be poured on the site, that’s why I built the base frame so stout. The runoff from the roof will be gathered into a barrel for watering the plants. Every thing will be grown in raised beds or buckets with no runoff. I am pretty sure I have all my bases covered, but worst case scenario is I would have to move it. In my past experiences with the DNR, they have been pretty good to work with as long as you do what they tell you.
GC
Garry, you may well be aware of this, but the University of Minnesota has posted a lot of good info on DWGs: Deep Winter Greenhouses | UMN Extension
Hans, that’s where I got the idea to build one. I was going to build one pretty close to their plans until I checked with the DNR.
GC
