Not an ordinary creek crossing

[tamu94]

How much does it flood?

A mile and a half down the road (and down the creek), a guy put in some nice piers, a truck flatbed trailer, and built up the approaches. First good gully washer we had, washed out the approaches and shifted the trailer half off the piers. The second gully washer washed the deck downstream a couple of hundred feet and buried 90% of it. Just the one corner is visible.

My first bridge washed out twice. I used a 4' and 2' tin horn with 2'X2'X4' limestone blocks. The blocks held but all of the road base and fill kept getting washed out when the water went over. It was only a matter of time before the entire thing got swept away.

I ended up replacing it with a concrete low water crossing and two 2' tinhorns for drainage. I might not be able to cross during high water events but the water drains away within a day. If you build a bridge make sure it can handle the floods.

 

[Threepoint]

Strongly second the advice to consult with a civil engineer with expertise in road and bridge building before trying to do anything permanent. Especially if you're downstream from heavy woodlands. It would be a shame to spend several thousands of dollars putting something in, only to find out after the next big storm why the local farmers for years have done nothing but bulldoze the crossing as needed. A trailer bed on a sturdy foundation may be all you need to clear high water, but if the rushing water carries a large fallen tree along with it, you've got a battering ram that can take out most anything it runs into. Here in No. VA, the County tried several solutions to a popular trail washout over a couple of decades: Fords, Irish Crossings, double 4' culverts, flat, raised timber bridges. Nothing was a match for heavy debris swept along by flood-stage water. They finally put in a very expensive, engineered steel bridge arched high enough to allow for most debris. Not practical for most homestead owners unless it's the only point of ingress/egress!

 

[franklin2]

I have seen some old bridges that hold up for years using culverts like you said you have. Their trick was not to force the water through the culverts when it flooded. The culverts were cut at a 45 where the water entered, and the complete bridge was not very high. They also used concrete between the culverts, smoothing and tapering the concrete to the water line. 90% of the time the bridge was fully functional. During flooding the water and debris went over the bridge. After a flood there may be some branches and debris to get off the bridge, but the bridge was still there. It didn't try to resist or direct the water through it, it just let the high water run over it. You just have to make sure it's wide enough so the water doesn't wash out the approaches to the bridge.

 

[Ken45101]

I have seen some old bridges that hold up for years using culverts like you said you have. Their trick was not to force the water through the culverts when it flooded. The culverts were cut at a 45 where the water entered, and the complete bridge was not very high. They also used concrete between the culverts, smoothing and tapering the concrete to the water line. 90% of the time the bridge was fully functional. During flooding the water and debris went over the bridge. After a flood there may be some branches and debris to get off the bridge, but the bridge was still there. It didn't try to resist or direct the water through it, it just let the high water run over it. You just have to make sure it's wide enough so the water doesn't wash out the approaches to the bridge.

The bridge on our driveway is like that. It floods once or twice a year but only for a short time. County Engineer told me I needed twice the size to avoid water going over the bridge. ($$$)

The flood water was washing away the rock sopports under the approaches. Good solid concrete bridge though.

I poured a solid concrete block, about 4'cubed to protect the bridge pier and then dumped rip-rap (12" rock) on the upstream side and then poured concrete over it. Its holding well, almost ten years now. Probably will need a little more concrete in a few years

After a major gulley washer i may find a 20' log stranded on the bridge but the basics are holding.

 

[StormVet]

Thanks for all the input. I've lived here now 27 years. Seen it flood ( get out of banks) 3 times. I have an 18 acre hay field that the creek runs beside of. All 3 times about 2/3s of the field was under water. Anywhere from 6 inches to 1 foot deep. Most years it only gets level banks. Lots of water rolling for about a day or so. Mother Nature can be a beast some times. I guess I'll figure something out.

 

[tamu94]

I have seen some old bridges that hold up for years using culverts like you said you have. Their trick was not to force the water through the culverts when it flooded. The culverts were cut at a 45 where the water entered, and the complete bridge was not very high. They also used concrete between the culverts, smoothing and tapering the concrete to the water line. 90% of the time the bridge was fully functional. During flooding the water and debris went over the bridge. After a flood there may be some branches and debris to get off the bridge, but the bridge was still there. It didn't try to resist or direct the water through it, it just let the high water run over it. You just have to make sure it's wide enough so the water doesn't wash out the approaches to the bridge.

Yep - this is exactly how mine is. We call them hill country crossings. It required two full cement trucks of rebar reinforced high strength concrete to make the road and downstream outlet properly. The outlet extends 20' past the culverts to prevent erosion from undermining the road. The concrete is 5.5" thick between the culverts.

When it was done my neighbor joked I should have erected a bronze plaque. Its not going anywhere.

 

[Bison]

Thanks for all the input. I've lived here now 27 years. Seen it flood ( get out of banks) 3 times. I have an 18 acre hay field that the creek runs beside of. All 3 times about 2/3s of the field was under water. Anywhere from 6 inches to 1 foot deep. Most years it only gets level banks. Lots of water rolling for about a day or so. Mother Nature can be a beast some times. I guess I'll figure something out.

I would not spend thousands of dollars to build a bridge to access a itty bitty plot like 18 acres.
I have 60 acres on the other side of a small river on one of my quarters, there's no way i can recoup the money for a bridge in a hundred years.
It can bloody well stay natural, a home for wildlife,..they got to live too.

 

[RogueFab]

I would not spend thousands of dollars to build a bridge to access a itty bitty plot like 18 acres.
I have 60 acres on the other side of a small river on one of my quarters, there's no way i can recoup the money for a bridge in a hundred years.
It can bloody well stay natural, a home for wildlife,..they got to live too.

Hmmm. It doesn't have to pay off with money to be worth it. I would do it if I liked what the bridge allowed me to access.

Assuming it does...

You have to decide if you want to take on the risk of non-approved bridge building. If you ask the county, you might get caught. But you will probably learn more if you ask. Building a bridge with some steel and a rented welder and tying it into the ground with foundations isn't that tough, but with construction, permission is easier than forgiveness if you know what I mean.

 

[franklin2]

Hmmm. It doesn't have to pay off with money to be worth it. I would do it if I liked what the bridge allowed me to access.

Assuming it does...

You have to decide if you want to take on the risk of non-approved bridge building. If you ask the county, you might get caught. But you will probably learn more if you ask. Building a bridge with some steel and a rented welder and tying it into the ground with foundations isn't that tough, but with construction, permission is easier than forgiveness if you know what I mean.

I know some people need gov intervention and rules sometimes to save themselves from well, themselves. I guess there are a lot of people out there without much common sense, but all this gov regulation makes me tired after awhile.

I can see a poorly designed bridge damming the whole creek up and flooding out the neighbor upstream, or suddenly giving way and flooding everything below stream. That's the beauty of the low water bridge. The stream doesn't really know it's there during a flood.

 

[Byrdnyrd]

Building Bridges

Oh I would definitely ask your local Government for advice on how to go about this project!! So many times I've heard people say " those folks down at City Hall are SO helpful, I'm so glad I got them involved "

NOT!!

Buy another tractor for the other side of the River and hang a rope swing from a big tree!!

Mi dos centavos!

BN