Tower collapses [sort of]

I've decided that the Water Tower is NOT going to rise this year after all.

The technical issues are realitively easy to deal with. On the other hand, daunting are the many liability and health department issues to deal with as many of you have pointed out in your emails and I've learned in conversations with BM folk, and while there are ways of 'getting around the rules' I can't find one that really allows me to make the tower both available and safe to all.

I WILL be bringing Wizzard Oasis for those who stroll far from the city, and I'm re-considering a couple other shelved projects-one attempting to generate dust devils and another that involves a few widely spaced wind breaks for smokers & others looking for windbreaks on their way out to the Oasis.

Excuse the generic response. I got many emails, and want to get back in a timely fashion.

Sorry to raise hopes about getting you all high and wet.

Burningman 2002:
Water Tower

Note: My announcement in JackRabbitSpeaks just hit and a lot of folks have started sending emails. Be patient, I will answer all of them, but I'll be out of town for a couple days so it may take a little while before I can do so.
Water Tower

Float 30' above the Playa

Background:

  • Talking with Michael (the artist that made the cool, tall, abstract metal sculpture last year) I whined that I'd made things not that disimilar to his in the past but never at such a scale. His comment was on the order of 'don't let size get in the way'. I decided to build big-whatever the actual project was. I wanted something that wouldn't simply disappear on the playa as a couple of my past projects have.
  • I've made several metal trees over the years. My early thoughts were to build a wooden or metal tree resembling the 'Swiss Family Robinson' treehouse from Disneyland and movie fame, but it seemed a bit out of reach.
  • When I read that the 2002 bm theme is the "Floating World", the first thought that came to mind was the endless hours of enjoyment I've spent floating on inner tubes in a backyard pool-both as a kid, and during a couple of summers as a teacher when I didn't spend the summer taking classes.
  • Combine 'Big' and 'Floating'. Then toss in an 'erotic' TV scene from a million years ago (any other 40+ year olds know what I'm talking about?**), and you get "Water Tower"
    • A search of the web yielded a good design, but none of the sizes were given (hey-they understandably want to sell plans). I decided to set the scale to make the tower 24' tall at the base of the water tank-3 'floors' of 8' tall. The main legs to be beams made of 4 stacked 2x6s, all the other struts to be made from 2x6s used singly. I have since shown plans to my dad-a builder all his life-and have made a 1/12 scale model that I've shown to a structural engineer. Both suggested that the structure as designed should be capable of holding up the weight I intend to load it with:

  • 8' diameter x 3' deep water tank (the pool on top) if totally full has water weighing:

    (3.14)(4')(4')(3')=~150 cubic feet x 64 lb/ft3 = 9600 lb

  • 10 people on top (more than I think can easily fit) and 10 more on other floors:

    150lb x 20 = 3000 lb

  • weight of tower=~4000 lb
  • Total loaded weight=~17,000 lb

    Wow! this is the first time I've seen the numbers all at once. When I said I wanted to build big, I didn't realize how heavy big is!

    • Not shown in the images here are several features:
    • Safety Railing on top floor. As well as providing security from falling, I am thinking that the 2 sides facing toward the wind (see below) will use the railing to support some sort of wind block-most likely fabric of some sort.
    • Plywood floors 8 and 16' above the ground. The top floor, supporting the water tank, will be robust-2x6 joists with 2x6 planking. The lower floors need hold a far smaller load and will be plywood on 2x6 joists.
    • Ladders between floors. I thought about putting ladders on the main legs 'outside' of the tower, but I have safety concerns with that arrangement.
    • Wall coverings. I have plans for only the top 2 floors of the tower (see more on planned use below), and will probably use fabric to close up and block the wind on the floor just below the water tank. I have no plans yet involving covering the bottom 2 floors.
    • The Floating Foundation (see below)
    • Water lifting system. This was actually the thing I planned first-before the tower idea came along, and may not get realized this year. When thinking about the Swiss Family Robinson treehouse idea, one of the key features I wanted to include was a chain driven 'bucket brigade' lifting system to transport water from a ground level tank to the top, using muscle power to drive the chain. Time will tell if this is gonna get done in time...
    My chat with a structural engineer made me feel that the structure is plenty strong enough as long as the base doesn't settle differentially. If this was to be a permanent structure, I'd start with massive corner concrete foundations, indeed that is what I just finished pouring this weekend in the back yard. For Burningman, 2 reasons I can think of make this a bad idea.
    • I don't want to dig up 4 big chunks of concrete and I can't leave them behind
    • The Playa is dry sand floating on wet mud.
    The solution that seems obvious to me is that I need to 'float' the tower on the playa by increasing the surface area of contact between the base and ground. I had always intended to have 'footpads' that would be attached to the 4 main legs and staked into the playa with rebar. To that, I plan on adding 4 footpads for the 'middle legs' of each of the 4 sides, and some 'laddering' around he entire 60' perimeter of the tower.

    My engineer friend said that building code allows for structures to rest on the ground (without having to perform a soil capacity test) as long as the ground loading is 2000lb/sq. foot or less. I'd like to drop that by a factor of 2 or 4 (1000 or 500 LB/sf) to be on the safe side. That means that I need to have a total footprint between 17 and 34 square feet--a figure that should be very easy to meet. (the 8 footpads-if 2' in diameter each-provide 24 sf towards this total).

    The wind load on any structure on the playa is important to keep in mind. If I planned on leaving the sides uncovered as shown in the images on this page, wind would not be an issue at all, but I do intend on enclosing part or all of at least a couple of the floors.

    I don't think it is going to be a major issue even with a tower as tall as this because of the amount of weight of structure and load. Still, past experience tells me that it might be a good idea to orient the tower so that the prevailing wind is as shown rather than having the tower present a big flat face to the wind.

    Wanna Help?

    I'm into building, and building and transporting this tower is gonna take all my time and efforts. It strikes me though that there may be some people out there with some good ideas that require them to stick their bit of BRC high off the ground. I have plans for the top 2 floors-there are 2 floors (well, the ground is one) for which I have no plans.

    Also, I want to be able to get out around the town and not just hang around the tower all day. I don't mind just locking it up (don't know how I'm gonna do his yet) when I decide to go for a cruise, but there will likely be many folks who will want to float 30' over the playa when I want to be out wandering.

    My thoughts:

    • flags, windsocks, wind structures
    • neon lights, led displays, nighttime lighting
    • airplane launch pad, music system, dance floor
    • midday cool spot-shaded interior space
    Your thoughts?

    Got a good idea? Send me an email at wizzard@wizzard.com. (I live in San Jose near Milpitas-if you are near and want to get involved-contact me!)

    Latest Developments

    1. I'm gonna get a LOT of flack when I erect this tower in the backyard of my mobile home. I put down 4 one foot diameter concrete foundations for the tower, and then changed plans somewhat to cut down some of the problems that will follow. Instead of building the tower right on the foundation, I've nearly completed a deck that will permanantly reside in the yard, big and strong enough to use 'temporarily' to build a tower on it.
    2. I have a pool for the water tank at the top. Got it online for only $229 complete with filter, ladder, etc. All I need to add is water and some pool chemicals. Also, the weight of water estimated above will be a bit lower. The pool holds around 1000 gallons-about 8000lbs.

    UNknowns
    • At the BM town hall meeting, I had a chane to chat with some of the official-type folks who gave me some good suggestions and possible stumbling blocks. Since it will be open to the public, the pool is going to have to be certified or licienced, or something-need to find out what...
    • Still not sure how or where I'm gonna get 1000 gallons+ of potable water (again-since it is open to public) or how I'll be lifting it up to the pool. I hope to get some good advise from someone who may have had the same problem in the past.
    Progress!

    I got the deck done, upon which I will be building the tower. Click the picture if you want to see the building of the deck.

    **Remember the intro to "Petticoat Junction" and the 3 girls in the water tower?, petticoats hanging over the front; encouraging naive young boys to imagine the scene within the water tank.