Water Treatment Tower repaint ideas 7

[looksatstars]

We are repainting the inside and out of an existing water tower. It is a welded steel tower that is 80 feet high and 12 ft in diameter. It was built around the 1970's.
I was thinking it was an easy job of removing old paint and putting a new potable water compatable paint on, but after taking with a paint distrubuter, I am seeing its a bigger job than i thought.
For instance, if the outside of the tower has lead paint, it will have to be stripped off and the dust in removal has to be contained. The structual integrity of the tank should be assessed when paint is removed.
Also that the painting of the inside can run around $6-7CDN per square foot.
If anyone else has any input on what to watch out for, I'm all ears.
Thanks

 

[rconner]

I don't have any experience with such operations, other than believeing you when you say this is a bigger task than most lay folks might think! However, I think I did happen to see a quite detailed article not long ago in an AWWA Opflow or Journal recently where a quite similar sounding case study was highlited. I think AWWA may also have some other publications and/or standards (and maybe even a video) discussing tank maintenance operations, including re-painting etc., so they along of course with EPA and OSHA might be good resources. I would suspect safety etc. is emphasized in all this. Hopefully you'll get some more experienced responses.

 

[bimr]

Steel tanks are frequently repainted every 10 to 20 years depending on the coating system that is applied. Just find a reputable contractor.

 

[Pump2005]

We just had our million gallon tower done. Sand blasted and painted in and out. Had to have scaffolding and the entire tank enclosed to contain the lead paint. Took about 3 months.

 

[semo]

There are many coating systems available.

The condition of the existing coatings will help dictate what type of system you use.

Besides sandblasting to metal, dealing with lead abatement, and recoating; there are also overcoat systems available. They may just require a pressure wash with power tooling prior to coating.

A reputable paint rep (such as Tnemec, Sherwin Williams, etc.) should be able to help by looking at the existing tank, performing some adhesion testing, etc and then providing a coating system.

Other options also exist to help contain the lead without draping the entire tank. We've used torbo blasting (water/sand blast) with blastox followed by a brush blast to remove the flash rust.

 

[JStephen]

Test for lead before you do anything else- I don't think it's that hard to do. It will simplify matters if it doesn't contain lead. It's been quite a few years since lead based paints were commonly used on tanks, so it seems like there are fewer and fewer lead jobs.

Tnemec has a lot of information on their website. From a contractor's standpoint, try to avoid anything too exotic. Normally, we're seeing epoxy inside, epoxy/ urethanes outside, with or without zinc primers or clear overcoats. The cost on this tank will run on the high side per square foot due to the small size.

 

[JedClampett]

I'm surprised nobody has mentioned AWWA D102. It's the standard for coating steel water storage tanks. It has a good commentary and some discussion of recoating existing tanks. You're definitely going to want to reference them in your specifications.
As JStephen said, usually on new tanks we use a potable water grade epoxy (two or three coats)on the tank interior and an epoxy (two coats) and polyurethane on the exterior. Tnemec and Devoe have products specific to water tank coating and their representatives are pretty knowledgable.

 

[bimr]

You may consider having the tank inspected prior to painting. There are many firms that specialize in steel tank inspection service such as Nelson Inspection, Lansing MI and Dixon Engineering, Lake Odessa, MI.

These firms are able to do a structural inspection and evaluation of the steel as well as the coating system. They would be able to recommend a coating system as well.

 

[marktbuckcon]

We painted a 30' dia. x 110' tank. The exterior we used a enclosed spider called and "E tank". With a high capacity hepa vac. The E tank saved the cost of enclosing the structure with staging and tarps. We attempted at first to satge and tarp the structure but the wind ripped it to shreads. We used Tnemec costing system. The inside was painted off a marygoround with supplied air to the personel.

 

[niibii]

You may want to consider having the tank inspected prior to painting. We used a firm called TIC in ours. They can also recommendations as well.

 

[looksatstars]

well I had the water tanks inspected. One did not have any lead paint, so it will be a straight paint.
The other had lead base coat and then another non-lead on the outside. So I can encapsulate the tower in a new coat of paint.
After 40 years the insides are starting to show wear from rust so i will be looking to getting those coated as well.
Though the proposed cost was 6 times my estimate.