Building roads in wetlands

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Hump is 110% right. Wood does not rot under water...I'd courdoy it with 2"-4" pole wood first myself.....if the DEPA would allow it..

Yep, we're using skidding roads that are courderoyed with cedar poles that my Grandpa made in the 1940's.
 
Hump is 110% right. Wood does not rot under water...I'd courdoy it with 2"-4" pole wood first myself.....if the DEPA would allow it..

If its completely submerged and in anaerobic conditions then no it wont. If it dries out or the base becomes exposed it could be a whole different story though, and that could get real messy to fix. My point is that if the OP wants to run a bunch of trucks across this road and then use it as his only access to his house there's better ways to build a road base
 
Puncheon Road

Okay, as far as I've seen the only real good advice you've gotten is from Humptulips. I build an average of 5 miles of this type of road every summer. Our wetland classifications are different, and different ones require different mitigation, it looks like you have that taken care of.

As for the construction you are way off base. I think you said you have 250 feet to cross, so we have 2.5 stations of road.

Don't stump the R/W, the stumps are holding your surface together, and will support the next layer you put down. Take all of the R/W wood and brush that you cut, and lay the logs perpendiscular to the road, and fill in with tops and brush where you can. This is 'puncheon', walk all of this in with an excavator, and pull other stumps from outside the R/W and shove them in the wet spots upside down so you will be filling on the spread out roots. Use fabric next, if you like wasting money; the puncheon works better than fabric when you use enough of it. Now you need to rock it with pit run rock. Put it down in atleast a couple of lifts, walk it in with a tracked machine, top it with some nice crushed if you want since it is a driveway. All the roads I build are permanent forest roads. With enough rock you can grade them as they tend to settle over time, and you won't be cutting into the puncheon. I regularly use 100-120 cy/sta of pit run on these roads. So you are looking at a minimum of 30ish loads over puncheon. If you dump the rock in by itself, even true rip rap, you will use far more rock as it sinks, the puncheon spreads the load of the fill and vehicles out over more surface area.

You will have to run solo trucks for the first lift, and they will have to back in and dump at the cat. If you get a decent first lift on, you may be able to run truck and trailer in for the second lift, and have them spread their way in, dropping your trucking cost a bit. Compact every lift with a virbratory roller to minimize the amount of rock you need.

As for pipes, there are many variables. If you have actual streams, there are some engineering calculations you can do to determine pipe size based on a bunch of variables. Or make an educated guess based on experience like we do in most cases. If you just have standing water, you only need to provide connectivity of the wetland from one side of your road fill to the other so your new 'dike' doesn't dam up the water on the high side. 18" pipes in a few places will work for that. Without seeing anything, I can't tell you how many you need. For a shallow filled road, with a 12' wide running surface I use 24' pipes, if the fill gets deeper, or the pipes are on a skew or in a curve, we get into 30'+ pipe lengths. Double walled, smooth bore plastic pipe is better than the metal pipes and the single wall plastic for passing debris, but you probably won't have that issue. In my budgeting, I cost the average 18" crossdrain pipe installed at $1000. Expect to pay around $500 just for an 18"x24' pipe. The other $500 in my budget allows me machine time for install and rock loading, truck time for rock haul, and a percentage for the development of my rock source....and its a bit high, so I can have soem extra money at the end of the year for additional projects.

Whatever you do.....DO NOT excavate the 'goo' and stumps on top. You never want to build a road in a trough, especially in a wetland. As soon as you excavate the goo, with is potentially endless for all intents and purposes, you are working in the lowest part of the wetland....where does water go? The low point...bad juju. I'll have to find you some good pictures of this type of construction.
 
I built a driveway in 2008 almost exactly the same as what you're doing.

No fabric was used. . . Big, big, (did I say big?) boulders as a base, then 5" or better river rock, then decomposed granite was used.

There was only one culvert 36" at the little creek that ran down the center.

Bedding the culvert properly is important. Also, excavating a pool on the entrance and exit of the culvert, and ripwrapping correctly.

The beauty of using rock as base, is the water flows through it in the event of high water, and there are no fines to wash out.

Also, ditto to not disturbing the base by removing anything.

I can dig out some pictures if you'd like. . . I have them on a cd somewhere.

Also, this kind of thing really isn't rocket surgery. ;)
 
A couple things to add. . .

The rock was all 'mined' from the property, which saved a buttload of money.

If you don't have rock on the place -- you might be selling a kidney to truck it in.

Another option for unstable soils, is helical piles/piers.

I've personally spec'd them out on a few jobs, and was aware of their usefulness before many others in the valley (thanks interwebs). They have been used for foundations since Great-Grandpappy was in diapers.

You might consider a girder and beam bridge across the swamp. Any local helical pier contractor can soil sample the area and calculate screw pitch and diameter for needed load. Price out some steel beams for the span between piles and bearing. Deck the darn thing in wood you mill right off the place.

Might end up being cheaper than all the rock you'll need. . . Agencies are also more prone to helical pile install in 'wetland' because of their low enviro-impact.
 
In my area (Stanwood Washington) a land manager of a Church property went ahead and did a project in a wetland without county consent or a permit and got busted big time he thought he could buy another piece of property and say that was the wetland; it's on the same road (300th street just down the road). Right now it's going thru the court system we will see were it end's up

Update: The Church had a $5 G fine and had to replace the wetlands with a 2 acre piece of land

And now they have posted signs saying what is happening there which they didn't do the first time
 
jim you might research rail road flatcar for bridges.i believe their as long as 89'.three of them acouple of piers,a crane seems like it would be alot more fun than throwing rocks in a swamp
 
Great question, wrong forum. Try heavyequipmentforum.com. I'm sure lots of guys on here have built roads. But I'm sure lots of road builders have cut down trees, doesn't make them tree experts. Road builders don't care what type or what size trees are in the way, just how wide the road and how long?
 
Didn't mean to sound unfriendly and I'm sure everyone is trying to help, but your getting responses that are all over the board from all over the country. seems useless like 20 gallons of what if. The answer to your question is site specific and designed to your needs/budget.
 
I'd love to see some pics of whatever you guys have done, if it's not too much trouble.


Status right now: waiting on a meeting with the township on Oct. 30th to see if they want to vacate or build the road which was technically abandoned in the late 60's. Neighbor wants it vacated, but I'm going to try to force them to build it for me and assess all of us (I don't like the other two people who would be impacted - they're mooches). Either way I win. :)
 
permanent road

consider the corduroy road option, as others have mentioned. or other options, which others have mentioned first. we have built roads over
70 year old corduroy roads, where the excavated cedar logs we excavated looking just like fresh cut-down timber. the logs are laid down side by side and do a good job of stabilizing the soil.
if it were me, i would still strip the 18 inches of peat before using this method. this is a good way to bridge over unstable soil.

that said,
this will undoubtably be the most costly option of road building. but if you want permanent, and if you have the bucks. to build a permanent no bull#### road over unstable soil:

-----------------------

now the fun begins.

probably the hardest part is to get a track hoe, dozer, and dump trucks to get in there to do the job without getting stuck. a working platform, a pad, most likely will need to be built up to get the track hoe stable enough to dig and load trucks and to get the loaded trucks in and out. if this cannot be done, it's game over. i have seen CAT 345C track hoes stuck, CAT D8's dozers stuck, various makes of end dumps stuck (off road dumps) stuck.
to add to this, i have seen all three of these get stuck trying to pull just one of them out. those are highway building size machines. even experienced folks who have operated hoes for 25 years can not walk them out in all instances.

on road 10-wheel dumps get stuck very easily. dumping or loading them on unstable soil is dangerous.

during excavation, even the hardest soil that is dry, can turn into a 4 foot deep mudpit after a storm fills the hole.

if,

the soil under the peat is stable (could potentially hold a load), you could potentially build on that, only if it is not clay/silt. but, since it is under the water/table already, at minimum, it will need to be dried out first, before it can support a load. until the underlying (oversturated, waterlogged) soil is dried out, consider this soil to be unstable.

this step is difficult.

to dry it out, construct retention ponds, dig swales, ditches or lay pipe to move the water as far away from the road as possible. it could literally take months before things dry out. exactly how you will dry out an area which holds runoff for 160 acres with natural springs in itself is could most likely be an impossible task. overflow from the pond(s) will need to be diverted away as well.

but in case you are able to accomplish this,

you have have an 18 inch depth of peat muck. this is considered unsuitable material. by definition organic.
this will never hold any form of compressible load, even if dry.

this will need to be stripped off.

so,

250 x 12 x 1.5 feet = 4500 ft3 = 166 CY (dug and moved and/or trucked away)

next,

the road will have to be higher than existing water table (-) the 18" of peat you just removed.
so, you will need, to fill the future road with some kind of "stable" soil/stone/gravel. this is called embankment.
get the elevation of the road as high as money allows.

roll the embankment with a dirt roller in static mode, until you are well above the water table. also consider that the weight of the embankment will settle over time. do not use a plate tamper! the vibes will cause more problems than help. consider the water table height change at spring thaw and/or rainstorm conditions.

if the embankment is high (thick enough) enough, the following steps other than the test may not be necessary.

build up the embankment in layers, and find the thinnest embankment layer that can pass this test.
roll a filled dump truck over the embankment, watch for "pumping". if the tires of the loaded truck, look like they are riding on a pillow, the embankment is unstable. this can be addressed by undercutting the unstable soil. this unstable soil is dug out and replaced with stable soil. if digging deeper to find more stable soil does not work, (and it rarely will in a swamp)... an undercut combined with geo fabric will be necessary. if a layer of geo fabric combined with an undercut will not do it, then a layer or geo fabric, then geo grid with a deeper undercut is used.

at the point where.... the added thicker layer of gravel becomes more costly than the fabric, use the fabric. also vice versa.

some geo-fabrics claim to be equivalent to one additional foot of gravel undercut.

another way to avoid this entirely, is to keep adding embankment lift layers, until this whole problem is solved.

at this point, you are ready for the next step.

once the embankment lift can pass the truck test, you can begin compaction using vibration. do this in equal lifts if possible. if you have a source on your land for this, great, if not trucking can be expensive.

next,

some quick math:

i do not know, what material you will be using, or the height of embankment material you will be using.....

the following math could be used for embankment as well. any non-organic, stable when dry soil coild potentially be used.


for the 2' depth gravel you will need to place over the embankment material:

driveway length = 250 ft
guessing width = 12ft
depth (fill) = 2 ft

250 x 12 x 2 = 6000 ft3 (cubic feet) = 222.22 CY (fill needed)

weight of gravel approx. = 110 #/ft3 (this will vary, but it's a conservative side value that we use)

so,

6000 ft3 x 110#/ft3 = 660,000 pounds = 330 tons

so,

330 tons divided by 22 tons (max. legal load on a 10-wheel dump in my state) = 15 loads

keep in mind, more than this amount will be nessessary. for potential undercuts, and the fact that the x-section of a road is a trapezoid shape, where the base is wider than the top surface, and also working platform. also much of this material will be wasted, lost sinking into the existing ground.

consider at least 2 feet of gravel minimum. if there are pipes under the road, take into consideration the recommended cover necessary over the pipe. this will vary with type of pipe used (corrogated steel, plastic, etc.) if not enough cover over the pipe is used, it will eventually collapse.

pipe sizing diameter, is based on runoff area, total volume, and existing slope. this is beyond the scope of my reply.
seek advice for this.
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as others have said, here, be careful in a designated wetland. use approved methods of construction (erosion control) or hefty and i mean hefty fines can result. i could not be doing what you want to do where i live. even ponds require a permit here.

also, ponds can fill up over time and will need to be mucked out. consider that when digging the initial depth
and use the clay/silt to line the bottom of pond.

good luck
-OMB
 
I'm probably meeting with the TEP panel in November (first tuesday). Still haven't gotten in touch with the township (either of them), and am heavily leaning towards a traditional corduroy road with geotextile.

I want 20' of width, so we aren't having vehicles trying to pass on the shoulder in the swamp. 16' might be sufficient, but I'd rather have and not need than need and not have. Especially when the foundation work is the killer in this situation - there's no adding later.

I'm clearing several acres of trees for my projects, so getting the needed timbers for the substrate won't be any expense beyond time and chainsaw incidentals plus fuel for the atv. It also provides filler for the depth needed to return to grade after removing the muck. If I was comfortable using aspen, I could fill the entire void with wood and not even lose timber value - I'm not comfortable using it, so I'll stick with the oak and maple I remove from my home plot and shooting range. The ACoE guidelines state 2" minimum diameter logs - that's not a problem at all, and will help with my forest management objectives as well. I'll retain the good bigger wood for milling later on, and sell the tops for firewood.

Where this project differs from what most of you might be used to, is that I don't have any time deadlines, or profit margins to worry about. I have no intention of building anything up there for the next two years (aside from small utility type sheds), and I enjoy doing this stuff.

Once again, thanks for all the input and help. :)
 
More info? We need more info. What is a type 7 wetland?

Type 7 Wetland: Minnesota DNR

I also appreciate it's wildlife attributes and actually want to dredge it out and make it more standing water

A good deal of irony in that statement.
Dredging will change the entire hydrology of your wetland, and impact your road building plans. I'd either not dredge and build the road, or dredge first, and then build. Dredging will cause you some major headaches down the road, in my opinion.

Do you have any pictures of the place, Jim? Pictures of the process are always fun to see here as well.

Also, one of the best road building manuals I have come across in recent years can be found here:
A Good Road Lies Easy on the Land Head to page 36 for the wetlands section.

Something else to think about, over 50% of all wetlands in N. America are gone. That's a lot of free flood control and wildlife habitat that has gone bye-bye. And people wonder why levees fail in big storms? Cause the wetlands are gone.

Good luck, Jim.
 
I'll be adding two more sequestration ponds up stream from this spot. More wetlands than I'm removing, and better quality for more animals use. As the swamp sits - the coons rarely go through it because it lacks much open water. What water there is breeds mega frogs (I'm ok with that), but little else. The black ash are dying because the township raised the water level when they changed the culvert depth. I'm going to lose all my trees if I don't do something - dredging should help. The "puddle" area I'd like to expand houses fish (minnow size only), and the occasional muskrat. It's not big enough to protect any birds. The rest is just muck with debris rotting on top of it breeding mosquitoes by the billions.

Pics of my land are in a thread in the pics section. I don't have much of the swamp, or even all that many of my property for that matter - because it all pretty much just looks like a bunch of woods: which is what it is. :)
 
Tonight was the township meeting about the platted road - 2-1 vote in favor. :D I no longer have a public legal access dividing two of my parcels.

I emailed the county wetlands guy to see about getting on the docket for next weeks TEP meeting to get that ball rolling.
 
They want me to come in from the south east, and will be investigating the best access point and how to deal with the neighboring land owner.

In all, I think that's the best option too. It's high ground, and much flatter from there to the house site. :)
 
There's a lot of down sides to where they want me to come in - less secluded entrance, interferes with my rifle range, neighbor who's land I'll cross wants a king's ransome for selling them, and could become hostile if eminent domain is used for easement, and it goes on...

One major problem with going through the swamp: will the beach road handle loaded logging trucks? None of us are confident it would.

They're open to possibly letting me build a driveway access through the swamp, but we all know that's either going to cost a fortune up front, or be an up-keep pain forever (or both). I'd rather not have extra two-lane roads through my woods, so it'll be a one road proposition.

My current trail will remain for atv and foot traffic.
 
There's a lot of down sides to where they want me to come in - less secluded entrance, interferes with my rifle range, neighbor who's land I'll cross wants a king's ransome for selling them, and could become hostile if eminent domain is used for easement, and it goes on...

One major problem with going through the swamp: will the beach road handle loaded logging trucks? None of us are confident it would.

They're open to possibly letting me build a driveway access through the swamp, but we all know that's either going to cost a fortune up front, or be an up-keep pain forever (or both). I'd rather not have extra two-lane roads through my woods, so it'll be a one road proposition.

My current trail will remain for atv and foot traffic.

Good luck with that, Jim. If I were your neighbor, you'd have 3 choices: build your access elsewhere, pay my asking price, or spend 3x my asking price in legal fees trying to prove your driveway NEEDED to go there, and then likely still have to pay my asking price or close to it. Eminent domain for private use is a real hard sell to most any court, much less one in a rural area where almost all the people who elect that judge are property owners.
 
Maybe look into having an engineer take a look at your two road options. Have him come up with an estimate for cost of construction for both spots. If option 2 + the cost of buying access is still cheaper then crossing the swamp, then there is your answer. Hel he might even see a third option nobody looked at before. The only down side is said engineer will want to get paid...everybody wants some...
 
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