I'm trying to design a footpath for a muddy long area with poor drainage.
Path is about 100 ft long and four feet wide. During heavy rain it builds
up a two inch lake of water. Could someone criticize the following design
for draining this area and building a walkway over it?
1) Dig a ditch and test that it drains correctly.
2) Line ditch with plastic allowing about 1 to 1.5 feet of extra plastic on
either side of ditch.
3) Lay down 1.5" drainage rock in ditch and on either side of ditch.
4) Lay down 1.5 to 2" thick flagstone, approximate 2 foot square slabs,
along the path, left loose on top of drainage rock and pressed down to
settle flat on that rock.
5) Lay down about 1" of wood chips on top of remaining drainage rock, to
provide safe footing for anyone who steps off the flagstone. This part
may not work very well if the occasional high wind hits the area or
gardeners use blowers and end up spreading the chips irregularly.
Alternate ideas for top layers would be appreciated.
Any variants on the above and reasons for the alternate design are
constructive criticism or just plain criticism Will? If the latter, give me
a few days to build a mock up and my wife will tell me everything wrong with
it, why didn't I ask her, how it looks wrong, this should have been there
and that should have been here....
Do you mean drain by running off or drain by percolation? If the former are
you able to maintain a slope? If the latter if it gets muddy now why do you
think it will percolate better after digging the ditch?
I'm no pro but what's usually done if drainage is a real problem is to use
4" drainage piping (the corrugated stuff w/holes in it) on top of your
gravel to actually move the water away from the problem drainage areas. You
need to maintain a slope of about 1/4 inch drop per foot to ensure the water
Why? This will impede percolation if anything. It might provide a more
freely flowing watercourse if that's your intention but I doubt it's worth
the effort and expense just for that. I suppose it would cut down on
erosion if that's an issue but unless the slope is significant you're not
going to get water flowing fast enough to cause significant erosion. If you
really need to ensure the water will flow w/o causing erosion use piping as
You'll want to top the drainage rock with sand and tamp it down well to
provide a solid level surface for the flagstone.
That's very thick flagstone. Flagstone I'm familiar with is more like 1/2"
- 3/4" thick. Using the thicker stone will raise the cost quite a bit and
be that much harder to install (weight). Any reason for selecting stone so
Those are my thoughts. Again not a pro, just an experienced homeowner, so
apply the appropriate amount of salt. Good luck.
We need drainage, and thankfully the area has a good slope.
The intent with plastic was to stop erosion and possible caving in of the
What about using Pea Gravel instead of Sand as the top layer above the
Would we need to rent one of those big rollers that is used to compress
material? What's the best procedure for making the top layer as
compressed as possible?
What is the appropriate thickness to support a 300 pound person (let's use
that as a VERY worst case).
Ok I reread original post and hadn't appreciated the scale of this. I see
what you are trying to do with the plastic.
The problem with this is that you aren't controlling where the water flows
and you are subjecting your flagstone foundation to this uncontrolled flow.
Ultimately gravel and sand is going to shift and your flagstone will as
well. If you use mortar those joints will crack.
This is what drainage pipe is for. It controls where the water flows and
leaves the gravel and sand foundation undisturbed.
Earlier I suggested corrugated plastic drainage pipe but for your
application and conditions it sounds like you may even need something more
substantial. I'm our of my depth here so I can't make a recommendation.
Certainly not without actually seeing your property.
Pea gravel isn't suitable. You really need to use sand if you don't want
your stones to shift about. There are websites out there that can give you
detailed instructions on laying flagstone with and without mortar. For a
patio tamping by hand with a tool made for such is fine. You are trying to
essentially build a 100 x 4 foot road. That's an awful lot to tamp by hand
and the engineering may be such that you really need to compact that with a
roller. I'm not qualified to tell you even if I could look at it.
You could find this out from a place that sells the stone. I'm pretty sure
that ordinary flagstone would be fine. 300 lbs isn't all that much weight.
I don't want to be discouraging but you are trying to build a 100x4
flagstone road that you know will be subject to adverse drainage conditions.
I'd consider getting the advice of a pro.
The concrete guys wanted $5K to build just a trench, and $12K to build a
sidewalk. We are the tenants, not the landlord, and the landlord is
refusing the solve the problem. I have about $3K to spend.
The fact that you're willing to dump 3k into a rental is... Well..
Look at doing something like this, which will be the base of your work.
You can lay the flagstone over this for stepping stones.. No need to
over complicate things, but the stones will shift.. I'm however assuming
that you're looking at leaving gaps around the stone.
You'll need a place LOWER than what the water is currently at to drain
to. Perhaps run it around the house and drain down the driveway if it's
Then just do something like this with the flagstone:
If the problem area is wide, you may want to do something almost like a
reverse leech field, such as having the main french drain, but have sub
drains point to it, like this..
^ to storm drain.
This will drain a wide area to a central pipe which can be as stated,
ran to a drain or driveway or some place ON THE SAME PROPERTY.. It's
illegal to drain onto someone elses land.
Keep it simple.. Start with the french drain system and then if you want
to go further after it's shown to do the job, add the expensive
flagstone over it as a path.
Here's another site you may find useful which is a person doing a
shallow fench drain system to drain surface water from against their house.
They also go so far as to plumb the gutter down spouts into the system,
which is where a TON of water comes from.. It's amazing how many
thousands of gallons can come off a roof in just a simple rainfall.
At any rate, my advice is to keep it simple.. Keep it running down hill
and get the problem taken care of before you make it pretty...
But then again, is it really worth it for a rental? That's up to you all
so I'll leave that as an opinion.
If possible, some pictures of your yard may help anyone on the group to
help you all and may aid in further advice. Hard to give advice blind. ;)
Sometimes your only choices are all bad choices, and you want to find the
least bad option. I'm not thrilled about spending anything much less $3K,
but simply cannot afford to dump $12K into this, which is what professionals
want to do it.
Thanks. And that illustration is helpful.
What happens if you line the ditch with plastic and then fill with 1.5"
drainage rocks, but do not put in the perforated tube? I guess the main
issue is about preventing the water from rising too high and upsetting the
sand or gravel top layer?
That much was clear, and we have the ditch running into a storm drain.
The entire situation sucks. We were the only building tenant and so had
exclusive access to the limited front parking area. The landlord found a
tenant for other side of building, and they are now filling up the front
area, requiring us to park in back of building, and find our way through mud
and dirt to the front. The next door neighbors are selfish in their
thinking about this problem, taking a "first come first serve" attitude even
though their side of building has parking lot surrounding it on all sides
and ours only has the limited front and back parking. The building
management is simply lazy and doesn't care. So we got screwed for not
anticipating this in our lease, and now we just have lots of bad choices.
I'm willing to spend the money as an act of good faith to our employees,
simply so they don't have to suffer through a ridiculous condition.
Water, much like electricity follows the path of least resistance. When
you have a problem with standing water you not only want it to flow
away, but do so as quickly as possible to prevent a buildup. The tube
just provides a clear, clean path for the water to escape quickly.
Also, the holes point down not only to allow water to leech out, but
also leech in.. When water is high, it will flow in through the holes
and follow along the path of the pipe to the exit location with is down
Very good.. I'd found over the years to make sure I'm clear with info
and assume nothing.. Saves headaches for myself.. and others, for that
So this is a business location? That might explain the first notion that
pops into my head, which is moving..
Also, you mention parking.. There would be no parking/driving over the
drainage system area would there? If so you'd need to build it up
further to prevent the collapse of the pipe.
Now, as for material I prefer the PVC pipe because it's smooth on the
inside and I feel it drains much better but there is also the black flex
tubing which is made for drainage that you could use. Since it seems to
be just minimal foot traffic you could use it, just offset the flagstone
so that the pipe is to the side of the path.
The bright side of the flex tubing is that you have some leeway as to
how straight your trench is.. Digging a straight trench is a bit of a
pain.. It's also cheaper... I'd quote Lowes.com but I can't find it..
They do sell it however.
Gravel wise, call someone to dump a load as you'd never want to buy bags
for something this large.. Just give them the depth/width/length of the
trench and they will give you an estimate on how many ton of chip gravel
Do a little searching for materials.. You may be in at just $1k in
material costs.. And alot of back breaking labor. Find your material
source, plan it out and you can easily minimize the financial loss and
have a system in place which should last 5-10 years without issue. Just
need to know what to trade off on.
Oh.. Plan to incorporate a few cleanout caps so that if there are
problems with clogs, a plumber can blow the system out with a pressure
The cost of moving would be huge, far far in excess of the cost of fixing
the problems with access on the side of building. But the landlord didn't
do himself any favors for when it comes time to move for other reasons.
This is clear. I meant employees are parking in rear of building and
walking to front of building through the area we are trying to build a
walking path in.
At this point we have spreadsheets that calculate cubic yards, tons of
different types of materials, and I'm starting to have nightmares about rock
deliveries. :) So this part of the whole thing I have covered. It's
more the basic engineering design that I want to make sure gets done to a
Can you elaborate on that? A cleanout cap is just a t shape pipe section
that is capped on top, to allow access into the pipe from the top? A get
the gist of it anyway and it sounds like great advice.
IMHO I think you need to look at this a bit differently. You need to call
your attourney. In any jurisdiction if you have an employee who trips due
to unsafe walkway or walk area or whatnot on the landlord's property, the
landlord is liable for their medical bills, not you. It is only your
the employee has entered the location your renting. But out in the parking
or walkway from the parking lot to the building entrance, it's the landlords
problem. For $500 you can have a lawyer explain this to them in legalese.
Also, the lawyer can explain that if the state workmans compensation
company were to investigate on a workplace safety that the landlord would
be cited as things are now.
IMHO spending your money on a building common area is incredibly dumb.
If you put any kind of structure in there, and someone trips and falls on
then the landlord will just sue you for the medical bills and likely win.
the landlord can simply wait until you have the thing completed then call
in the building inspectors and make you rip it out.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.