New ramp issues

[Joe Blizzard]

They just finished building a new launching ramp a short distance from my house this summer, and naturally I was pretty happy about it. The first time I used it, I noticed power boaters struggling, and when it was my turn, I understood why. Even with my truck backed in to the front doors, there wasn't much water under my boat and I had to do a lot of pushing to get it off the trailer.
After a lot of complaints, the owners (WVDNR) had an as built survey done and found that what was supposed to be a 13% slope was actually only 8%. I have a Facebook post here with an illustration of what this means. They brought in a barge and crane and "tamped" the concrete slabs with a piledriver hammer to correct the slope. There are photos and video on the city's Facebook page showing the work being done.
During construction, the slabs were cast on site and then shoved into the water with heavy equipment. That probably would have been a good time for the contractor to verify the slope angle, but you know, measure once, cut twice, or whatever.
I haven't been back since the adjustments, and probably won't be until I take my boat out for the winter in a month or so. Anyway, I thought some of you might be interested. I'm attaching a couple of images for those who don't do Facebook.

 

[jssailem]

And they say engineering is a science and not an art. Sometimes they screw up. Now it will be intersting to see if they put any ridges in the concrete slabs. As the algae (mother natures slippery plant) starts to take hold of the smooth concrete it can overwhelm the wheels ability to pull a car and boat out of the water. This makes for great videos as the car tries to get traction pulling the boat out while car, trailer and boat slowly slip back in to the water.

You might want to take a video camera along to your pull out. You might just get images for the next viral YouTube blooper.

 

[LloydB]

The diagram shows what happens to the slope on one end as it gets deeper but the diagram does not show what happens to the end of the ramp under the water at the deepest point when it gets shorter. I don't see any real gain when there is a foot of mud or more sitting above the end of the ramp during low water.

 

[Joe Blizzard]

Update: The DNR wasn't satisfied with the results of the tamping. The new ramp has been demolished and will be rebuilt at the contractor's expense.

Lloyd, lowering the low end of the ramp won't put it below the natural level of the underwater terrain. The slope of the river bank here is much steeper than any practical ramp slope, and has to be built up to support a ramp. We generally have the opposite issue here on the Kanawha, with a substantial drop off at the end of the pavement.

 

[Joe Blizzard]

There's a video here, taken during the reconstruction. The way they built this thing (both times) was to pour a slab up on dry land, shove it down the slope into the water, then pour another slab behind the first one and shove them both the rest of the way in. I don't know if this is a common way to do it, first time I've seen it.

 

[Crazy Dave Condon]

@Joe Blizzard

Do you recognize the spot. End of the New River and beginning of the Kanawha River beside US 60.

Where is the ramp. Dealt with WVA DNR AS a sailboat dealer. Ugh. I once heard “Winding in Winding fills my mind with serious doubts, whether the fool or fools that sketched those routes was going to heck or coming out. Apply to DNR IN YOUR CASE? Earlier in life I rode a cart between two towers overlooking the site before the New River Gorge Bridge was built. Use to be an investigator in WVA Did you know the first high rise parking garage in the country was built in Welch?

 

[Joe Blizzard]

The ramp is at mile 33, downstream from the falls at Glen Ferris by 60 miles, give or take a few. (I live at mile 34.) The source of the Kanawha is a little ways up from the picture, where the New and Gauley rivers conflue at Gauley Bridge. My wife used to work for the company that did the engineering design for the gorge bridge. I didn't know that about Welch.

 

[Crazy Dave Condon]

I was told different but thank you for the correction.