[cameron]

******************************PREVIOUS POSTS*****************************
Dave



Joined: 30 Dec 2003
Posts: 611
Location: FSK
Posted: Tue Feb 02, 2010 5:24 pm Post subject:

--------------------------------------------------------------------------------

I'm all for doing the Waka. If for no other reason than to follow thru on our permit so we don't look like a bunch of ne'er-do-wells to the Corp who went to the trouble of getting us the permit. I also think the Lawrence guys need to take the initiative since they will benefit most.
All it will take is finding some local rock that will lay in like a stone fence.
So which one of you playboat maniacs want's to step up, buy some rock and call a work day. I'll show up to help. Might call the Lew and Dave, the dam guys, and see if they are still with us on this baby and when they can shut the dam water off completely.

Back to top


cameron



Joined: 26 Apr 2009
Posts: 11
Location: Lawrence
Posted: Wed Feb 03, 2010 8:13 am Post subject:

--------------------------------------------------------------------------------

I am all for helping out with the waka project, and if anything else were to be kept up I would like to see the forum stay around because I probably wont join ACC. I have talked with a few other Lawrence paddlers and they are in for the job as well. We should probably start work soon before the rainy season hits. Is there any money saved up for this project?

Back to top


Fish



Joined: 06 Jul 2009
Posts: 81
Location: Wherever there's water
Posted: Wed Feb 03, 2010 8:29 am Post subject:

--------------------------------------------------------------------------------

I'm in for helping out with Waka. I've never even been there, but I know that if you got a permit, you'd better do something with it. Those things are rare and precious. Let me know when and where to show up to help with Waka - or I can research rock too, but I know no one in the area to start talking with (you might talk with stone-masons about cheap "reject" rock or maybe with farm co-op folks about any farmers who are looking to get rid of some annoying rock on the cheap - not sure if there is much of that up here, but back in NW AR, there was tons of it to be had. Otherwise, go to the quarries directly and trying to get some of their crappier stuff cheap - we probably don't need good landscaping stone, right?).

Seems like little (if any) support for an ACC chapter up here. I'll be happy to do the paperwork to get one going, but I'm gonna have to have folks coming to me who want to see it happen. I do want to get boatball going again this summer. Getting out every week and paddling the hell out of my boat for a couple hours has gotta keep me in shape for several great Colorado weekends in June and July. And maybe for an Idaho trip if the lottery gods smile on us.

- Fish

Back to top


Dave



Joined: 30 Dec 2003
Posts: 611
Location: FSK
Posted: Wed Feb 03, 2010 8:48 am Post subject:

--------------------------------------------------------------------------------

When I posted a year or so ago about becoming a chapter of ACC I got about a dozen folks who were interested. I didn't pursue it anymore but who knows, maybe we could get 15 this time.

As for the Waka. Shawn and I visited a quarry that is just a couple of miles from the Waka. It is shot rock, meaning it just random shapes and sizes. We can certainly afford a whole truckload of that stuff. They even said we could stand out there while they are loading and choose our rocks (somewhat). We would need someone with a hard hat and steel toed shoes to be our man at the quarry.

The main issue would be to cull out rocks that are too big for two guys to move.
Any volunteers to pick up on this lead.

Back to top


cameron



Joined: 26 Apr 2009
Posts: 11
Location: Lawrence
Posted: Wed Feb 03, 2010 8:57 am Post subject:

--------------------------------------------------------------------------------

I have a hard hat and steel toe boots, so that is not an issue for me. I assume you are talking about Hamm quarry? I will talk to some people and get back to the group once I know more.

Back to top


Dave



Joined: 30 Dec 2003
Posts: 611
Location: FSK
Posted: Wed Feb 03, 2010 9:23 am Post subject:

--------------------------------------------------------------------------------

That sounds good Cameron. Our info came from the guy in the shack at the quarry several years ago, so no contact has been made yet with the business office people. And yes it is Hamm.
Another couple of issues. We should check to see if we have the go ahead to just dump a whole load in the riverbed below the ledge. Then we will have to set up a time with the COE to turn the water off. That may be June or July, who knows. Also, Kevin has the contact info for Dave and Lew at the Dam. We should get the permit reconfirmed before we leap.
We submitted plans for the ledge and amounts of material and some of the logistics of placing the rock when we got the permit and I can share that with you.
Let's hear some chatter from the group. Who wants to pump rock sometime this spring or early summer? We had really good participation when we built the trail.

Back to top


Dave



Joined: 30 Dec 2003
Posts: 611
Location: FSK
Posted: Wed Feb 03, 2010 9:32 am Post subject:

--------------------------------------------------------------------------------

Looks like we got kind of a double thread going here. Sorry for hijacking the club future thread, Kevin, but I think the Waka project is probably our biggest piece of unfinished business. If it wasn't for that we could use the money for a party or to join the ACC. At one time we had $1000 or more. Anybody know or could give us a guesstimate.

Back to top


3featherslanding



Joined: 13 Jun 2009
Posts: 24
Location: Lawrence, KS
Posted: Wed Feb 03, 2010 9:57 am Post subject:

--------------------------------------------------------------------------------

I am also in on the Waka. Spoke with Craig (Puppy)-- he has a contact at Hamm's Quarry, all different sizes of rock available.
_________________
Dave B

"The mountains are calling and I must go."

--John Muir

[Dave]

At one point we thought we needed real regular rocks to lay in under the ledge but the more I think about it the old stone fences sure didn't have regular shaped rock.

We probably want to do something like this, except ours will lean back against the ledge more than this picture. The bigger the rocks the more stable it will be.

[cameron]

has anyone done/have research materials on making a wave like this, I would just be curious to do a little research into slope angles and shapes?
Glenwood Springs looks like they have a similar spot.
There is a video here http://www.glenwoodwhitewaterpark.org/action_video_4.html

Anyone who has been there want to comment? all materials/info appreciated

[Dave]

Yeah, I based the design on Salida , Buena Vista and Pueblo holes. Ideally the rim of the ledge should be lowest at the middle to accommodate lower water levels but unfortunately we don't have the option to modify the ledge itself, just add rock below. The angle is the important thing. I showed 35 deg I think on the drawings with is pretty close to Salida. At that angle the wave should be pretty much unchanged at 1000 CFS and hopefully will be improved at lower levels like 500 and below.

[spartacus9]

I'm a Lawrence local and would be more than happy to put in the time and effort, whether that's hauling rock or whatever. Could probably round up a few additional hands too with the lure of beer.

[KUKayaker]

I'll check the bank account and see how much money we have but I think one of hte first orders of business to see how much the rock is for just shotrock vs. something more stackable and determine our cost. If we can work out that and schedule delivery all we really need to do is pick the date.

We had to get an extension from the corps on this but I can double check it's valid then work with them to schedule something at no flow.

A note on putting the rocks in is I don't know if we'll be able to get less than the 7cfps that they release all the time. There is a pool under the ledge that I doubt would drain out completely even if we ran no water. At that point our options are working in there or somehow pumping it out past some bags etc.
_________________
kukayaker = Kevin

[Shawn]

I am highly doubtful that the permit is still active. A phone call to Dave or Lou in the Corps office could confirm.
_________________
Shawn
----------------------------------------
www.kansaswhitewater.org
NØCH

[Josh L]

I did a project using a water tunnel for my lab 3 project this last semester that helped determine the hydraulic jump of running water. If you can determine the velocity of the water before your wave along with the initial depth of the water right before the wave it will give you an idea of the depth needed at the crash (where the fast water hits slower water causing a jump) for an good wave. Its not an exact science but it can help on deciding what kind of angle will give you a good hydraulic jump. Here is link that will give you calculations to help. Our project produce some killer waves on a small scale that could possibly be scaled up with a good understanding on what depth and angle would give this type of jump.

http://en.wikipedia.org/wiki/Hydraulic_jump

[Dave]

That's pretty cool Josh.
So how would we determine the velocity of the water above the ledge.
We know the CFS coming out of the dam about 1/2 mile up stream, we have a consistent cross sectional area of the channel. I suppose we could shoot the elevational change between the dam outlet and the ledge. Or we could just go out there and measure the speed.

Our tail water is variable depending on how wet the rest of the watershed is. We may have to guessimate the height of the drop over the ledge to the tailwater.

Lots of unknowns, I'm afraid.

We do have observation at various flows however, and many of us are intimately familiar with the forces in the hole, both on the surface and below the surface. Har har.

I copied the angle at Salida to draw the cross section but it would be interesting to see how it would calc.

[Josh L]

Q = Z2 W (2 g Z1)^1/2 This will give you a flow rate (Q) The Z2 will be your depth at the ledge before the jump and the Z1 is the depth above the dam. g is the gravitational constant 32.2 ft/s^2 or 9.81 m/s^2 for you SI people. W is the channel width and the 2 is also a constant that comes from the derivation of this formula. Q will be you flow rate in cubic feet/s and can be converted to velocity by dividing by the cross sectional area at the ledge.

You can always let something float a distance down the river and time it.... and get a distance / time.

There are also tools that can measure this such as a pitot tube that measures pressure in order to get the velocity. This would probably be to costly to justify though.

A Fluid Dynamics book could be a cost efficient way that has examples to determine what you need.

[cameron]

I have a fluvial hydrology book somewhere from college, I will have to try and dig that out because I know there would be some useful stuff in that. Thanks for the info josh. I think a tennis ball would probably suffice for our purposes of estimation of speed, maybe a tennis ball with some sort of weighted sail attached to grab some of the undercurrents. Does anyone know where we are at with the permit to do the work, anyone in good with the guys at the dam, Lew and Dave?
Here are the outstanding items I see need to get done before work can start:
1. Contact Lew and Dave
2. Find out about our permit
3. Find out the cost of Rock
4. How much money have we got to spend on this project
5. Relearn fluid dynamics and fluvial hydrology/review plans for creating a new wave
6. Find a date that will work for a large group of people to do the work, we are going to need a large number of people because that is a lot of rock to move.

I think the first thing to do would be to find out about the permit, so if anyone knows about that I would much appreciate any information.

[Fish]

That's a good Wikipedia article on hydraulic jumps - thanks for the link John. As I'm sure you guys know, fluid dynamics is complicated stuff. Some of the most complicated stuff man has ever put his computing power toward. The more turbulent the flow, the more complex it becomes to "do the math" and make specific predictions about flow. For example, stream velocity is a three dimensional phenomenon, taking surface measurements of velocity may or may not give you an idea of what the velocity is in other parts of the flow. Depends on a lot of things...

I like the idea of modeling the system, but just keep in mind that as John said, "it isn't an exact science." It can sometimes not be even close, and it generally takes quite a bit of engineering experience in that domain to get good results. If Reynolds and Froude aren't familiar names to you (http://en.wikipedia.org/wiki/Reynolds_number, http://en.wikipedia.org/wiki/Froude_number) then consulting a hydraulic engineer can't hurt.

If you want help building a scale model, let me know. Whether or not they predict what the full-scale features will look like, I love building scale whitewater models (who doesn't?)!

- Fish

[Dave]

We know what the wave looks like at 1000 CFS. Seems to me you could measure the height and frequency of the wave , knowing already the height of the drop and measuring the speed of the water you could possibly piece the unknowns together and determine the height of the wave at say 500 CFS. Although I agree with Fish that all the calcs are just academic when it comes to creating the characteristics we want.
Rather than height of the wave I am more interested in the steepness of the greenwater and the exitability of the hole.
We all know from being in the hole that we want the green water to be fairly low sloped and manageable eddy walls for getting out.
Here is the drawing that was approved with the permit application. The only thing they objected to was any cutting of the existing ledge, so we wouldn't remove any rock like the drawing shows, we will have to just fill in underneath. The angle of the new rock is about 35 degrees and is based on getting a gentle angle of greenwater in the hole. Similar to Salida

[KUKayaker]

As for the permit, on Dec 8, 2008 we filed for an extension which gives us until May 31st of this year to complete so I think we should be good on that front.
_________________
kukayaker = Kevin

[Dave]

Excellent. I hope we can get a dry period with zero or minimum release before then. I think if we make a reasonable effort (like getting rock delivered) the corp would let us wait for the right dry conditions to place the rock. I suppose we could work in knee deep water but the quality of the ledge would probably suffer. I think our original permit allows us to tweak the ledge after we get the initial rock placement done.
That leaves two questions.
How much money do we have ?
and
What are the particulars of getting rock from Hamm?
If we could get delivery on the north side of the river they could probably just dump the rock down the hill and right on top of or just below the ledge. That would make a lot less flip flopping of rock to get it into place.
Let's get the Hamm arrangements set. I'll be happy to get some steel toed boots and join in the rock selection.
Cameron , have you had any luck yet calling Hamm.