Bridge Questions

[CurlyDave]

...I am curious as to what your opinion would be on a vented ford such as this which is designed to be flooded. Culvert Case Studies > Rocky Creek

That is a darned nice crossing.

One thing to note is that it is a crossing, not a ford. The difference is that a crossing is intended to be periodically submerged, but to spend most of its life above water. A ford is underwater most of the time.

I think an issue you are going to have to face is that the stream gets much wider than normal when it floods. The approaches and abutments are going to have to be very, very good.

 

[tlj87]

That is a darned nice crossing.

One thing to note is that it is a crossing, not a ford. The difference is that a crossing is intended to be periodically submerged, but to spend most of its life above water. A ford is underwater most of the time.

I think an issue you are going to have to face is that the stream gets much wider than normal when it floods. The approaches and abutments are going to have to be very, very good.

It is really nice! I have been reading through "Low-Water Crossings: Geomorphic, Biological, and Engineering Design Considerations" from the USDA (Watershed, Soil and Air Technology and Development Program, Home Page) which is has a lot of really good information (385 pages!) including case studies on various types of crossings that have been used and how they have held up. FWIW, this document calls the above mentioned structure a "Vented Ford with Concrete Box Culverts".

 

[big e]

I had a very similar challenge at my place. After a couple years of hand wringing and talking to many many people I went with a reclaimed fuel tank. 8 foot diameter takes a large amount of water. Here are some pictures. My creek gets up like yours does and goes back down, but yours carries more water and gets much wider. Maybe you could get by with a pair of 8 footers... but you'd have to dig a channel so all water goes through and they would not over top.
I don't know what the PA code people would say about their use. Mine is out of sight and would not cause any damage if they'd back up/dam up. It was a bunch cheaper that concrete. And a bridge is ever more.

On the other hand, its almost 2020, we should be getting flying cars any day now.

 

[RedNeckRacin]

The existing ford is in good condition with a solid bottom and approaches. The water depth May-October is typically 3-5" and can be crossed by car. November-April varies more, perhaps 12" on average. Still passable with a truck, but I do not like to cross during freezing weather and then letting a vehicle sit. At one time (sometime prior to 1939, based on old aerial imagery) there was a dam or some other structure spanning the creek near the ford/bridge site. There are two railroad ties in the bank at two locations, one near the ford. As a general rule of thumb, if the water level is over the railroad tie, then we usually don't cross.

In terms of permitting, I have a call into my local conservation district office who, according their website, handles the permitting. They have been on site previously and organized the streambank planting project (which we'll be continuing this spring). A "GENERAL PERMIT BDWM-GP-7 MINOR ROAD CROSSINGS" is what seems to be required. This is through the DEP. Here is a link to the PA Code re: Permits for Bridges and Culverts. 025 Pa. Code § 105.151. Permit applications for construction or modification of culverts and bridges.

A gp-7 I understood to only covering agricultural use? Activities Waived at 25 PA Code ｧ 105.12(a)(7)(8) - Waiver 7 and 8 - Activities Related
to Crop Production: This is limited to maintenance of field drainage systems for crop
production and for plowing, cultivating, seeding or harvesting for crop production. This
corresponds to activities authorized pursuant to PADEP Waivers 7 and 8.


I very very strongly suggest that you contact your local DEP water quality specialist, the EPA, as well as the Army Corps of engineers. The fines for pollutional discharges to waters of the commonwealth come with fines, but the feds can bring felony charges. I'm really not trying to be a pain in the ***, but if you have already informed a state agency of it, you might as well do your due dilligence and my sure you CYA. (Cover Your A@#) I dont deal with the conservation district much, but they dont have any teeth for legal enforement, the other agencies do.