Pedestrian Bridge

[Arkansas Rio Gator]

I have been informed (elsewhere) that...

"There are going to be a lot of stakeholders moving forward in the use of the new bridge and also the new dam underneath, with its kayaking flume, etc."

To these stakeholders and co. I would be tempted to say...

"The new dam, flume, etc., might be great, and there may be money to be made, but the new bridge itself is a mistake—downgrading from what we already had in key ways—and a preventable mistake at that (so much the worse). The 1917 bridge should not be demolished for it, of all possibilities. Clearly, many thousands feel this way; I have only encountered a small representative sample, already evidenced by the petition. Said stakeholders should read the 2015 HNTB report from beginning to end, for starters, and see about saving some money and keeping/renovating something truly unique. It ain't too late to stop this Brookside Blunder (or, anyhow, it should not be.) Have a nice day and Happy Thanksgiving."

[buffalodan]

Have you looked at the HNTB report?

They have the cred:

https://www.hntb.com/bridges/

Look at the numbers in their report.

I'm not saying that it is wrong, just that I would much rather have a contractor give us an estimate on something that is fairly abnormal. We are now comparing a 5 year old preliminary study done using RS Means and ODOT historical pricing to an as-bid price. They aren't really the same thing. I think your argument is strong enough that the new bridge as designed isn't a good use of our money compared to other options (KKT Bridge?). But I don't buy for an instant that we could rehab the old bridge for half the price of a new bridge. I think HNTB lowballed the repair option and we picked an expensive and bad new bridge.

Also, that is interesting about design-built. I think this would be a perfect implementation for it.

[Arkansas Rio Gator]

I'm not saying that it is wrong, just that I would much rather have a contractor give us an estimate on something that is fairly abnormal. We are now comparing a 5 year old preliminary study done using RS Means and ODOT historical pricing to an as-bid price. They aren't really the same thing. I think your argument is strong enough that the new bridge as designed isn't a good use of our money compared to other options (KKT Bridge?). But I don't buy for an instant that we could rehab the old bridge for half the price of a new bridge. I think HNTB lowballed the repair option and we picked an expensive and bad new bridge.

Also, that is interesting about design-built. I think this would be a perfect implementation for it.

Well, I myself can't say whether they low-balled, of course. So, at any rate, sounds like we agree it's time to get another estimate/do another renovation study/or come up with a better replacement and not just tear her down to make room for said expensive and bad new bridge. Works for me. And I agree, this seems to meet the design-build criteria cited above... (What can we do to make this happen?)

[Oil Capital]

I'm not saying that it is wrong, just that I would much rather have a contractor give us an estimate on something that is fairly abnormal. We are now comparing a 5 year old preliminary study done using RS Means and ODOT historical pricing to an as-bid price. They aren't really the same thing. I think your argument is strong enough that the new bridge as designed isn't a good use of our money compared to other options (KKT Bridge?). But I don't buy for an instant that we could rehab the old bridge for half the price of a new bridge. I think HNTB lowballed the repair option and we picked an expensive and bad new bridge.

Also, that is interesting about design-built. I think this would be a perfect implementation for it.

Why would HNTB have lowballed the repair option and on what grounds do you come to that opinion?  (It wasn't a bid to do the work; I'm just not seeing any motive for them to have lowballed.)

[Arkansas Rio Gator]

Why would HNTB have lowballed the repair option and on what grounds do you come to that opinion?  (It wasn't a bid to do the work; I'm just not seeing any motive for them to have lowballed.)

Something somewhat similar to this was said to me between my last post and this one. (Besides which...just my impression...if they were low-balling, isn't the high estimate of almost 20 million a bit high?! Now since I'm not a professional engineer, I can't check this for myself, but from what I've heard...)

I think, bottom line, it does seem pretty clear:

There is good reason to have confidence in HNTB's ability and in their having provided a reasonably accurate estimate. Their figures would certainly be considered significant evidence in a court of law, over and above any run-of-the-mill opinion. It's our best evidence at the moment...

Another thought: Imagine if the public had been told HNTB's full recommendations five years ago...

[Oil Capital]

Something somewhat similar to this was said to me between my last post and this one. (Besides which...just my impression...if they were low-balling, isn't the high estimate of almost 20 million a bit high?! Now since I'm not a professional engineer, I can't check this for myself, but from what I've heard...)

I think, bottom line, it does seem pretty clear:

There is good reason to have confidence in HNTB's ability and in their having provided a reasonably accurate estimate. Their figures would certainly be considered significant evidence in a court of law, over and above any run-of-the-mill opinion. It's our best evidence at the moment...

Another thought: Imagine if the public had been told HNTB's full recommendations five years ago...

EXACTLY, and why weren't we?

[buffalodan]

Why would HNTB have lowballed the repair option and on what grounds do you come to that opinion?  (It wasn't a bid to do the work; I'm just not seeing any motive for them to have lowballed.)

So I'm not saying that they did, but there is a ton of research about how projects specifically like this tend to have a very long tail on the expensive end. HNTB is encouraged to come up with a $10mil cost estimate so that they can hopefully get the design. Then you can start throwing fun add-ins and doing more due diligence to get to $30mil. So comparing a scoping estimate of project A to an as-bid to project B doesn't have a ton of value. HNTB may not have realized that OTA was taking up tons of bridge contractors, or that USACE would have more intense scheduling requirements. I trust the low end, but after dealing with more of those type of project engineers do a really bad job of determining the high end of scope creep.

Again, it isn't so much that HNTB is bad, just that there is a lot of research that engineering firms tend to underestimate how expensive public facing /art projects can get. I also want to again state that I still think for $30mil we could have covered bridge with lights and everything, just that saying "HNTB said that the bridge could be saved for $10mil" doesn't hold much weight to me.

[LandArchPoke]

When is the planned demo of the old bridge?

My question is why does the old bridge need to be demoed? I think the new bridge is supposed to be built north of the old bridge, right and it isn't in the way of the new dam I believe - could be wrong though?

Why not keep it open while we can and use it as the pedestrian crossing for walkers, fishing, etc. and the new bridge as a bike/other crossing for faster movement. Especially if we can't afford to install shade or any other amenities. Seems like a win/win and we get separated crossings.

I do get that at some point the old bridge will be unstable and need to be closed but I feel like from what other people have said and what other engineers have said is that bridge isn't in critical fear of collapse. Why not keep it around for another few years, especially until we have the ability to raise money to add shade, etc. to the new bridge. Maybe down the road we can figure out a way to keep both.

[SXSW]

When is the planned demo of the old bridge?

My question is why does the old bridge need to be demoed? I think the new bridge is supposed to be built north of the old bridge, right and it isn't in the way of the new dam I believe - could be wrong though?

Why not keep it open while we can and use it as the pedestrian crossing for walkers, fishing, etc. and the new bridge as a bike/other crossing for faster movement. Especially if we can't afford to install shade or any other amenities. Seems like a win/win and we get separated crossings.

I do get that at some point the old bridge will be unstable and need to be closed but I feel like from what other people have said and what other engineers have said is that bridge isn't in critical fear of collapse. Why not keep it around for another few years, especially until we have the ability to raise money to add shade, etc. to the new bridge. Maybe down the road we can figure out a way to keep both.

I agree with this in theory, but likely doesn't match their vision from an aesthetic standpoint.  The new bridge will be built north of the existing bridge.  This shows it well:


The future Jenks low water dam will have a pedestrian bridge, likely similar to the Big Dam Bridge in Little Rock:

[shavethewhales]

When is the planned demo of the old bridge?

My question is why does the old bridge need to be demoed? I think the new bridge is supposed to be built north of the old bridge, right and it isn't in the way of the new dam I believe - could be wrong though?

Why not keep it open while we can and use it as the pedestrian crossing for walkers, fishing, etc. and the new bridge as a bike/other crossing for faster movement. Especially if we can't afford to install shade or any other amenities. Seems like a win/win and we get separated crossings.

I do get that at some point the old bridge will be unstable and need to be closed but I feel like from what other people have said and what other engineers have said is that bridge isn't in critical fear of collapse. Why not keep it around for another few years, especially until we have the ability to raise money to add shade, etc. to the new bridge. Maybe down the road we can figure out a way to keep both.

The bridge IS in fear of collapse. The existing piers are dangerous and crumbling apart. The whole point of this whole ordeal is that the bridge isn't deemed to be safe in it's current condition.

The proposal to build new piers and move the bridge onto them is intriguing, but at this point it is a lost cause. I'm not happy about the bait and switch with the bridge design, or the fact that this option was kept hidden from the public.

I'm sure in 25 years there will be a new initiative to build a worthy, landmark quality pedestrian bridge somewhere along the river. 

[LandArchPoke]

The bridge IS in fear of collapse. The existing piers are dangerous and crumbling apart. The whole point of this whole ordeal is that the bridge isn't deemed to be safe in it's current condition.

I wonder if this is really true that it's in fear of collapse or it that's been a 'spin' put on it to push for the new bridge. No doubt there is deferred maintenance on the old bridge that needs to be fixed and I could be wrong, I haven't dug into the history of this much, but I was thinking the main obstacle to keeping the old bridge was that the piers would not support making it a double deck bridge and that modifications to the bridge to facilitate more capacity was far too expensive and we should just build new for that reason. I didn't think the bridge was ever in such poor condition it couldn't be kept in its current fashion for a while. The powers that be just wanted a bigger and nicer bridge that could have separated bike lanes and then an area for pedestrians.

Someone who has read through it could probably answer this, but did the HNTB report just talk about keeping the bridge the way it is and just transferring to new piers or did it go on to discuss that the new piers would allow for the bridge to be modified to a double deck situation that was wanted? Browsing through it this wasn't apparent to me at least.

Even if the piers needed major restoration for safety reasons - why not build a smaller new bridge just for bikes, runners, etc. and then fix the piers on the current bridge, add some new lighting to make it look better at night, etc. and then we solve several of the issues at hand. Seems like the money saved on slightly scaling down the new bridge could possibly pay for repairs to the old bridge to keep it acceptable for pedestrian use.

Seems like there is some solutions out there if the city and others wanted to make it happen, just not sure if they really do. Seems like the entire point of building new has completely evaporated with no shade, seating, and not really having proper spacing between pedestrians and bikes.

We're just getting a crappy version of a new bridge that will have worse functional utility than the old bridge just for vanity purposes to have a bridge designed by MVVA. 

[Vision 2025]

When is the planned demo of the old bridge?

My question is why does the old bridge need to be demoed? I think the new bridge is supposed to be built north of the old bridge, right and it isn't in the way of the new dam I believe - could be wrong though?

Why not keep it open while we can and use it as the pedestrian crossing for walkers, fishing, etc. and the new bridge as a bike/other crossing for faster movement. Especially if we can't afford to install shade or any other amenities. Seems like a win/win and we get separated crossings.

As I understand it the hydraulic model does not provide for "zero rise" (which is one of the design conditions) at the 100 year flood level with the piers from two bridges that close to the LWD.

[LandArchPoke]

As I understand it the hydraulic model does not provide for "zero rise" (which is one of the design conditions) at the 100 year flood level with the piers from two bridges that close to the LWD.

Gotcha, interesting and thanks for that info. Any idea on when the plan to demo the bridge?

I wonder if a solution could be to move the new bridge south or further north. If you move it further north then you'd have the benefit of a bridge for the northern part of the gathering place as well - like around where the stop light is... then you almost create a short loop and might encourage more people to walk around to both sides of the river. Might make the city property on the west bank more valuable that way too if they ever decide to vacate it and sell it off.

Benefit of moving it south of the new dam would be the river bank isn't as wide with the bump out that built near the skate park, so you'd gain some cost savings from a shorter bridge that could then go to fixing issues on the old bridge. Seems like most of the bikers/runners come from that direction and would allow for a bypass from the busier part of the trails around the park for people that use the trails for recreation purposes. Might help alleviate some pressure on the trail system through the Gathering Place. 

[Vision 2025]

I'm not part of the bridge team but can offer a bit of my observations.  I would imagine that any significant obstruction (of which bridge piers are) placed in the narrowed section at the Southern bump out would result in an unacceptable rise condition.  Additionally, at that location the West bank is owned by PSO who while very friendly to the projects, the reality is that their site is already congested with power plant infrastructure plus the levee easement which cannot easily be encroached upon without adverse impact.  In my opinion utilizing the existing West bank bridge landing location was likely a critical constraint and was a good solution to a difficult siting.

[Arkansas Rio Gator]

“Why not keep it open while we can and use it as the pedestrian crossing for walkers, fishing, etc. and the new bridge as a bike/other crossing for faster movement. Especially if we can't afford to install shade or any other amenities. Seems like a win/win and we get separated crossings.”

Not a bad idea. This project needed more creative thinking like this...


“The bridge IS in fear of collapse. The existing piers are dangerous and crumbling apart. The whole point of this whole ordeal is that the bridge isn't deemed to be safe in it's current condition.”

Is that quite right? Did you look at page 3-1 of the report? Note the third and last sentence ("...do not appear to present an immediate hazard requiring closure..." and "...regular inspection...") in the following paragraph. The actual concern seems to be about what might happen, eventually, if nobody pays attention or intervenes IF the cracks grow... I quote:

“Numerous welds exhibit defects that could compromise the reliability of the structure over the long term. Several welds appear to have cracked, and pose a risk to the fracture critical lower chords, suggesting crack growth could precipitate collapse. The cracks do not appear to present an immediate hazard requiring closure of the bridge, however it is not clear whether the cracks will grow and become unstable. The effort to grind out these cracks and replace the connections would be quite extensive given the large number of welds (numbering in the thousands). One alternative may be regular inspection to monitor the growth of the cracks over time.”


“The proposal to build new piers and move the bridge onto them is intriguing, but at this point it is a lost cause. I'm not happy about the bait and switch with the bridge design, or the fact that this option was kept hidden from the public.”

INDEED. And had I not started the petition, I would not have gotten my hands on that report which makes such clear. Disappointing.

P.S. Unfortunately, they edited out the interview details about the HNTB report, which it really seems someone did not want us to see. This mess would never have gotten this far with more transparency by the City. They also edited out any reference to single-deck restoration *maybe* saving 50% or more. Well, never say I did not try! ha

https://ktul.com/news/local/petition-to-save-old-pedestrian-bridge