Installing Slalom Course In Public River

[mbrannan]

Friends,

 

For many years our ski club in Ohio has used a public river for skiing. It's a very small river, where a small section is dammed for boating. 1 mile long, slow moving current, 10 feet deep, no tubing, no jet skis. Used for skiing, wake boarding, and fishing.

 

Our course is traditional set up, anchored north and south for gates, with mainline and river adopters at turn balls holding course in position.

 

It's a little tough to keep in good shape (ball height, slight course bow from time to time, balls getting knocked off, etc.). But all and all, it's OK. Certainly not record capable, but good enough.

 

Recently, a new club member has been encouraging us to make the course much better. More precise, straighter, safer, less maintenance. His solution is to individually anchor gates and turn balls to the bottom of the river. Placement via a surveyor. this would require a diver, special anchors, etc. We've recently used a diver to survey the bottom of the river - and there appears to be enough sediment to drive rebar through the anchors to hold them in place. The gentleman has loads of experience installing courses in this manner.

 

Nevertheless, we have concerns:

- stuff moves down river (logs, etc.). What if the anchors get moved - this would be very hard to fix on the fly (i.e. today's set canceled)

- river freezes in the winter, if sub-buoys are gone in the spring, how do we find anchors without a diver (river is murky).

 

In general, we'd like a better, stronger, safer course. But we're wondering about the maintenance issues surrounding this approach.

 

Anyone have any experience with a course like this in a river / public water way? Any advice?

 

Thanks in advance for the input, truly valued.

MB

 

 

 

 

 

[dstone124]

We attempted to install an individually anchored system on the white river in Indy two years ago. FAIL.

We utilized our existing cabled course to survey in the new system. We poured large concrete anchors with sub-buoys which we set at an established depth equal across the entire course. We installed the system in the fall before pulling out our cable system.

The following year excited to make a quick install on all our effort from a few months prior we searched the river to find that every single anchor had washed out. We later found them in the fall when the water was down below summer pool several hunderd yards downstream and around a corner.

The bottomline, Mother Nature is a powerful mistress.

My recommendation, try a test bouy / anchor or (2) before you get your hopes up and spend too much valuable volunteer time and money.

I commend your efforts! Good luck either way.

[mbrannan]

Thanks for the prompt response. Did you simply set the anchors on the bottom, or did you affix them to the bottom of the river? Our approach is to use rebar pounded into river bottom to anchor the anchors.

 

Love your idea about a test buoy. Seems prudent.

[dip]

We have a course on the Delaware River that is individually anchored. With the exception of a couple of bouys over solid rock, each is fastened to a steel bar driven into the rocky substrate. In our case, they have actually solidified in place over time (this was shocking to me).

The Delaware is generally slow moving with a rocky bottom. The course is in 6-8 feet of water. Heavy rains will cause the river to swell and float debris but so far we haven't had anything worse than a few lost balls. The bouys are connected to the anchors via a pulley and counterweight to make up for fluctuations in water level. It's certainly not a dream course but better than not having one. It is also susceptible to major damage from flooding but thats a chance we just have to take.

I think @dstone124's comments about a couple of test anchors is a good idea though.

[ToddF]

we have been talking about doing the same thing. But Once it is surveyed/straight put the portable course over the top. Attaching the Gates, 3 and 4 guide buoys, and each turn ball.

(Cheaper and easier then doing all of them) 12 anchors total

 

we have about two feet of rise and drop so we would probably use bungie cord after the sub buoys.

 

that way you are kind double protected.

Strong current isn't a concern for us.

[GregDavis]

I'm trying to help these guys, and share the experience I've gained over the past 30 years, traveling to different sites, and installing permanently anchored courses.

 

POSITIVE THINGS:

 

 

1. ACCURATE COURSE ( guaranteed to improve everyone's Performance)

 

2. easier to keep turn balls low for safety

 

3. way, less maintenance, less work messing around with course all the time.

 

4. simplicity

 

5. less expense in long run, i.e. replacing pvc arms etc.

 

6. DID I MENTION ACCURATE!

 

 

 

Any negatives can be easily overcome with a system. like locating the sub buoys and anchors in spring.

 

 

 

 

 

If cost / expense is a concern, that can be addressed. ( I would be willing to pay for entire project )

 

If, after one year using the new course people are happy and satisfied, they can chip in and reimburse me.

 

If not happy, put arms back on, and no one owes me a thing. ( Here is your TEST )

 

I am that confident that it will work and everyone will be very, very happy.

 

 

this is for 10 permanently anchored buoys, turn balls and gates.

They would use the existing center line cable for boat gates.

 

 

THE SURVEY COST WOULD BE $350

 

Material cost, excluding T's $355

 

 

 

Total cost ( excluding T's ) $705

 

 

 

 

 

 

 

 

Cons: One of the members listed possible cons below:

 

When water level changes buoys will require adjustment before skiing

 

WATER LEVEL CAN FLUCTUATE 8 TO 12 INCHES OR MORE, BEFORE ADJUSTMENT IS NECESSARY. VERY EASY TO ADJUST, TAKES LESS THAN 10 MINUTES TO ADJUST 10 BUOYS.

 

 

 

If anchor maintenance is required or anchor is moved by debris, water flow, or fishermen, repair requires a diver and new survey crew. No skiing until repaired

 

BEING THAT THE ANCHORS ARE IN 10 FEET OF WATER, AND THERE WOULD BE A BREAKAWAY SYSTEM. IT IS VERY, VERY UNLIKELY AN ANCHOR WOULD MOVE. WATER FLOW, OR DEBRIS WOULD NOT MOVE ANCHOR. IN ADDITION, THE ANCHORS WOULD BE RE- BARED INTO BOTTOM, THUS MAKING THEM VERY DIFFICULT TO MOVE. IF BY CHANCE AN ANCHOR WOULD GET MOVED, NO SURVEY NEEDED, THERE IS AN MANUAL WAY TO MEASURE PLACEMENT FROM THE SURFACE. AN ANCHOR COULD BE MOVED BACK TO ORIGINAL LOCATION FAIRLY EASY, WITHOUT SURVEYOR.

 

 

 

City of Columbus does not allow permanent fixtures using metal in the water system, this would have to be completed outside of City permission

 

ANCHORS WOULD NOT BE PERMANENT, JUST LIKE THE ANCHOR AT THE NORTH END OF SLALOM COURSE THAT HOLDS THE CENTER LINE IN PLACE.

 

 

 

If center line of boat guides is off the accuracy of the course is off

 

THE ACCURACY OF THE COURSE WOULD STILL BE SPOT ON, THE BOAT GATES COULD BE OFF IF A VERY, VERY SEVERE CROSS WIND. HOWEVER IF THE WIND IS THAT STRONG, IT WOULD BE USELESS TO TRY TO SKI ANYHOW.

 

 

 

Loss of the mini course that beginners are using today

 

EASY TO PUT MINI COURSE IN, JUST DROP SIX CEMENT BLOCKS WITH BUOYS ON FOR MINI COURSE

 

 

 

Someone has to swim each spring (or anytime a gate or turn ball come off) to install the course

 

CORRECT

 

 

 

Location of the turn balls and gates may be challenging to find

 

LOCATION OF SUB BUOYS IS VERY EASY TO FIND. AS LONG AS THERE IS ONLY ONE OR TWO BUOYS OUT.

 

 

 

 

 

If you guys want to do this, let me know. if not, thanks for the time, it has been nice meeting Randy and Mike. As we all share the same passion of slalom skiing.

 

 

 

I would ask that we make a decision by Wed. night. That way, I can order material Thur. they can ship material Friday, so I could receive by Wed of next week, which would give me a few days to string sub buoys and make anchors. If it is a go, we need to let Lex ( the surveyor ) know, so he can plan accordingly. shoot for Sept 22 nd. if a go.

 

 

 

 

 

Regards: Greg Davis 407-617-3417

[6balls]

In a floating course big debris can take out much more than one buoy or buoy line. We fluctuated a lot on our collegiate river course years ago. Some local "old" guys (you know, M3 age that ran 35 off) had a permanent course (all buoys) and we didn't like having to screw around with the water level issue adjusting all the buoys.

Seemed like we should go portable w/river adapters so at least it would be able to float up/down with the water. The elder locals who were moving away advised against, saying they arrived at perma-course after much headache with floating. They were right and the dumb, inexperienced kids (aka: me) were wrong.

Personally, I would let @gregdavis set you up.

Greg, why not permanize the driver gates as well?

Greg, if you were my partner and you made such an offer I would have you permanize both of our swamp courses, and try to talk both my alternate public lake guys into doing so as well. I would want the entire course done, though. I've skied plenty of crosswinds enough to bow a porta-course but not have unskiable water.

[sled491]

You guys are lucky, we can't put in a permanent course. There was one for years on the lake above me, but the DNR made them remove it this year.

[behindpropellers]

Where are you talking about?

 

I have a combination of a permanent course and floating course on our lake. The floating course gets pretty beat up. I ended up putting surgical tube from the PVC to the balls and it has helped. All balls are filled with water. Have only had to fix 2 balls on the permanent gate.

 

Get in touch with Greg Lanich for questions with getting the ODNR stuff through. I have drawings on cad of permanent course anchors for your permit. My good friend who is an excavator has helped us with setting the course up, GPS guidance to within 1/4". Drop me a line with any questions.

 

I personally would not drive any rebar into your river/lake. If it gets pulled out of the ground partially, it could impale a boat or person. I have 4" steel pipe in between our gates, it has not moved.

 

Tim Cochrane

tim.cochrane@gmail.com

Chippewa Lake Waterski Club

 

[lottawatta]

If I understand GregDavis' proposal above, he wants to have a floating cable mainline, and individually anchored skier buoys? If so, then I would second that. I do respect his opinion either way as he is a verteran course installer. If the thought is to put all 26 anchors in individually, this is a method I would only recommend on a drained private lake.

 

I put many courses in the Great Miami River over the years, and the biggest headaches came with the individually anchored course. The individual anchors (2'x2'x6" concrete with rebar) almost always had something caught on them, were constantly washed downstream by trees when the water was high, and were a pain to place and move. We fooled with various subfloats and counter balances. The best river course design we came up with was a high quality mainline with lots of tension and lots of weight at each end. I think our last slalom course mainline anchors were over 1000 pounds upstream and 800 pounds downstream with enough tension that you could walk on the mainline from boat guide to boat guide. Then we individually anchored the skier buoys using tires filled with concrete and rebar stakes through them. Subfloats were at 4' depth, and had light bungee line to the skier buoy that would break away easily when the fishermen tried to pull it out of place. I will admit though, our Great Miami River site has more current, more flow, and more trash than either of your two pools on the Scioto. 10' of rise and enough current to trick ski with a rope tied to a post was not uncommon for our site after overnight rains up north.

 

I have the survey equipment and have placed many courses in private lakes as well. There is no greater value than a well engineered, high quality, floating course from EZ slalom. Period. There is no reason that with the right anchors, tension on the mainline, and river current adapters, your floating course can not be made accurate. I wish I had his products to work with in the early 90's when we fought that river year in and year out. At the very least, use one of his heavy duty mainlines, then individually anchor the skier buoys to elimiante current and wind problems.

 

As far as permits go, I always think it is better to ask forgiveness than permission. As of right now, in Ohio, your permit would have to go through the local authority (presumably Columbus). However, in the near future, all courses in the state (public water OR private lakes) may have to be permitted through the ODNR. Proposed legislation is still pending on that.

 

Best of luck,

Lottawatta

 

[Edbrazil]

Ah, river sites. Can be OK; can be brutal. I had courses on the upper Connecticut River at one time. Usually well-behaved, except during Spring runoff. When I worked with the original Pro Tour, we went to many river sites. Typically, we'd put in a bottom-anchored course. Whether it would still be there when we returned the next year was iffy.

 

At Wichita, KS, all traces of the course were gone the next year. Site had other problems, with strong winds. Went upriver around the corner, and had great luck...one time. Next time, the current was 3+ mph and impossible. Drop a buoy w/anchor, even in the relatively shallow water, and the buoy got pulled down and under.

 

Currents over 1mph are a big problem. Surprising how such a seemingly slow speed current can make so much force. Many years later, on the Connecticut River at Hartford, CT, a current of about 1.5mph acting on a floating course with the River Current stays on the PVC arms was still strong enough to put a bit "U" in the arms and move the skier buoys in maybe 3 feet. Which became apparent when the first slalomer out ran out of shortline loops.

 

The site cited sounds relatively mellow. A bottom-anchored course with plenty of anchor weight, low-down subbuoys, and breakaway tension band should work. Occasionally, something is bound to get caught up on a buoy, so the breakaway feature is needed. With a floating course, this could damage the course structure. And, with a floater, it may take only one problem, including vandalism, to destroy the course.

 

A couple more river examples. At the 2003 PanAm Games in Santo Domingo, we put in a bottom-anchored course a few weeks before the event. When we returned for the actual event, a tropical storm had apparently wiped out the courses. But not the subbuoys. Only had to adjust or replace a couple of buoys. Site, even when nearly calm was one nasty river.

 

The Womens WOW Tour went to Parkersburg, WV on the Ohio River. That river was nearly wide enough so the SL course could have run from side to side. Big tugs pushing trains of 15 barges, fortunately well away from the event side. Current around 1mph or a little less. What we did after the first one or two years was to get a modified floating course made up. Starting with just the centerline cable and gates, then adding special cables made up by Accufloat to make a "frame" that went out the 11.5 meters each side to the buoy level. One large rectangle of 4 cables, 23m by 259m. So, we didn't have to use PVC arms, and had a whole lot less current/drag effect. The add cables were held and tensioned by 4 large anchors; one at each corner, and offset a good distance away. The only time I've seen this approach, but it worked then.

 

Anyway, I would give the bottom-anchored option a try. See a typical anchor in the attachment: chimney block with added concrete and a stainless eyebolt. 110+ lbs. EB

 

 

[9400]

Ed, do you know what they use at Moomba?

[Edbrazil]

Moomba: last there in 1991, but it was a side-to-side cable course. They have winch(es?) on the shoreline posts, so that the cable can be lowered out of the way of deep-draft boats. Which can snag the cable, and which I've seen when one comes through unscheduled. Also saw some hits and near misses with 8-oared shells. Including one rowing straight into the jump ramp high end...bonk. And Sue Lipplegoes jumping over one.

 

Probably the same deal there still. While I was there one year, the shore pins were measured by a surveyor and found skewed from one side to the other, and significantly. I believe that 38 was run for the first time when that got fixed.

 

Jump course buoys, mostly, are also on the crossline cables. I've seen currents there nearly sink the jump ramp twice, before the anchor lines let go. Lots of stuff floats down after heavy rains, such as nearly enough beer cans to walk on. Place would be a lot like if they ever held an event on the Charles River in Boston.

[9400]

Thanks