Large Scale Central

Construction Woes Need Some Guidance

General Discussion
#1

Guys, I’ve run into an engineering problem on my layout build and am in need of some help to come up with a solution. My goal is to build a trestle that crosses over a 5 foot wide stream that runs next to the house over to a second partition of the layout and back, but I’ve tried on several occasions to do this but as soon as any heavy rains come my work on the trailing side fails and compromises the stability of the footwork. before: Trailing Side

before: Pressure Side

Top:

This thing is strong and stable enough to hold me jumping on it but… When It Rains:

…

…

After the water recedes the Pressure side is still intact and the trailing side is washed, I’m trying to keep from using concrete as that creates another set of issues, like having to try to divert water while the crete sets up…which is nearly impossible. and I want to try to keep the area as natural looking as possible. As A side thought as seen in the pics above the water does continue to flow thru the dam at its base, I did that to keep the stream flowing I also have one 4" overflow pipe on the one side next to the patio to help with drainage and the other side drains thru the rocks next to the grass on the other side. I’m kinda at my wits end as this is the second time I’ve repaired this thing each time a little wider and with larger stone. and The Stream still wins, I have thought about driving posts into the creek bed but where we live is very rocky and it would take three 3 men and a boy to bust thru the rock to anchor anything in the creek bed, I’ve busted a mattock and one shovel trying to bust up and move the rock in the creek, which is where all the stone came from for the dam. and in order for me to span the creek I would need at bare minimum an 8 foot trestle to span one bank to another, you cant see for the tall grass but there is about a 2 foot high bank that I have to cross over to get to the main part of the layout when built, which begins when I get the trestle figured out. Thanks in Advance for any new ideas or suggestions I am really stumped here as I fear that no matter what I can think of or thought of and tried, the stream will win…

#2

Are you trying to block the water from flowing except in flood stage, keep the fill material inbetween the large stones from being washed away or keep the large stones from moving?
Ron

#3

They make concrete that’s designed to set up in submersed situations, so if you had to go that route, that’s one way of doing it. If I’m understanding your photos, there are times when the water isn’t flowing over the rocks, which would give you ample time to set in and put some concrete between the rocks so that it’s not visible.

Later,

K

#4

(http://www.trainweb.org/rgs/rgseast0005.JPG)

The only solution I can think of is building a bridge something like this, that will span the whole creek. I think anything you use that has any contact with the rocks in the dam will end up with a problem of some sort.

(http://www.trainweb.org/rgs/rgseast0009.JPG)

#5

Shawn. My experiences with water is that it is a fickle friend. Lovely to see and hear when in ‘quiet mode’ but awesome when in an aggressive state.

You will need, as I am sure you have realized, to allow for the worst scenario if you are to avoid heartbreak and damage to the railroad. You have had good advice so far, more will come I am sure, but I go with Ken’s idea of a substantial bridge which would not be dependent on the banks of the stream.

#6

You must be lucky to live where the government hasn’t legislated to protect all wetlands and water flow. Here I’d go to jail if I built what you have started so far. I have a blacktop sluice on the edge of my property for storm drainage from the street. The town considers this a watercourse and any permits I might need to build on my property need be approved by the Inland Wetlands Commission.

I’ll also agree with Ken on the bridge idea. Bridging the entire stream, higher than the 100 year flood level without any contact with the steam bed would be a way to avoid lots of future maintenance issues.

#7

Thanks Guys for the great suggestions,

Ken, Your idea of that long trestle is fantastic, When it quits raining I’ll go out and take out the dam and use the largest stones as an abutments mixed with a little concrete to support the new bridge.

Thanks Guys, I’ll post in a few weeks what I have built.

#8

What about building something similar to what I see on retention ponds. An overflow pipe that is above the normal water level upstream that exhausts out below the water level on the downstream side? Sort of like a washbasin overflow.

I dunno?

#9

Yes, Ken’s trestle idea makes sense.

Here’s another thought: My analysis is the rocks simply created a dam when the flow was greater than the water passage through the stones. Large concrete drainage pipes placed at creek base level with the stones on top may work also. I have used them as a base for walk-way bridges in a former koi pond. In your part of the world a short section of stand pipe might be the answer.

Wendell