Sunday, April 7, 2013

Maryland DNR Tries to Understand Bottom Paint

Many marinas are coming out with new rules for DIY projects. OFten the boat owners gripe, but to me, these rules are very reasonable. The below is from a Chesapeake Bay marina. My thoughts are added and underscored.
  • No wet scrubbing, hosing or pressure washing of bottom paint allowed while blocked on land. Would you want someone making a mess in your yard? Reasonable enough.
  • Use filter cloth or tarp when scraping/sanding. Would you want someone making a mess in your yard?
  • No dis-colorization may be noted on the ground under any vessel. Would you want someone making a mess in your yard?
  • ALL paint cans must be placed outside of the shop on pallets after use. Paint cans that contain any wet residue are very likely hazardous waste. They cannot allow you to place them in the dumpster with regular trash. You can of course take them home, dry them, and put them in the trash.
  • Do NOT throw any paint cans into dumpsters. Staff will properly dispose of paint cans. See above.
  • Do NOT throw paint brushes, rollers, trays into office lot dumpster if WET. See Above. I always leave them in a neat pile under my boat (on a tarp and covered by the tarp) when finished; by the time I come back to launch they are dry and can be pitched. Very eas and much neater than fooling with the stuff wet.
  • Put all used painting materials outside of shop for disposal by staff. See above.
  • Office lot Dumpster is the ONLY dumpster for commercial waste. Very likely it goes to a different landfill, rated for industrial waste.
  • ALL other dumpsters are for residential waste (trash, paper, bottles, cans, food, etc.)
  • If in doubt, place item outside of shop door. Staff will dispose of properly.
  • Shrink Wrap must be bagged and placed next to dumpster outside of Chandlery 
 "Please remember to inform the office of bottom paint applied. We need the date applied, manufacturer, type and quantity applied. Management must log paint applied on a daily basis and report to the state monthly."

 This all seems very reasonable to me. Most requirements are simply restating MD DNR regulations. The last line is intrusive, but as we will see, is logical for the marina.

Why do they need to know the type of paint? Maryland has passed a law that will restrict the VOC levels of paints applied, and marinas are only allotted a certain amount of non-compliant applications. Compliant paints contain less than 400g/liter VOCs.

Because they need to calculate the amount of emissions from paints that contain VOCs over the MD limit. You can get this off the MSDS or tech sheet. I found the paints I have used--I checked several and they were all traditional high-Cu solvent paints-- contain less than the mandated 3.3 pounds/gallon, so no problem. You DO NOT have to go to water-based paints, not in MD. Anything less than 400g/L will pass.

Pettit Horizons-------------323
Pettit Trinidad--------------400
Pettit SR 40-----------------330
Interlux Micron--------------330
Interlux Bottom Coat------465. And I bet this gets reformulated soon.

This e-mail has no impact on me, as I always did bottom painting this way. They are just asking us to be clean.

  • Let the marina power wash the boat where it can be contained.
  • Sand with a good vac set up. As a side benefit, you don't risk your lungs and the guy working next to you doesn't get red dust on and inside his boat.
  • Dry your paint waste and tools before you trashing them. Try to use all the paint!
  • Read the paint spec sheet. VOCs are easy to manage. 
And finally, use a 2-year paint. Just my opinion. But if I do the work only 50% as often as and annual practice, it just stands to reason the impact is less. Anytime you can benefit the environment, save money, and save work.... Well, the smart choice is just plain obvious.


  1. Lucky you in Maryland that all they are worried about is the VOC's.

    Here in Washington they are after the copper. Of course, the new law only applies to recreational boats under 65 feet in length. Not to commercial boats. Not to shipping. Not to the Navy. Just us little guys that can't effectively complain.

    Beginning January 1, 2018, no new recreational boats under 65 feet may be sold in the state of Washington if their bottom paint contains copper. Beginning January 1, 2020, no bottom paint that contains more than 0.5% copper may be sold for application to recreational boats under 65 feet in the state of Washington.

    s/v Eolian

  2. We bottomed our boat with the water-based bottom paint from Jamestown. What a pleasure to work with and really great results. A year later and we are clean and rolling at 7 knots, as good as we did when she first splashed. Totally happy with the paint and will not go back to the toxic stuff. Why is this a not more popular option?

  3. Which paint? I'm not married to any one product. Really, the point of the post was to encourage simple good practices and to encourage readers to look at and understand VOC ratings.

    --I'm don't consider solvent-based paints difficult to work with. Either way, the brushes and rollers are disposable. I generally find solvent-based products easier to work.
    --I'm not certain the toxicity of the minor amounts of solvent is important in the big picture, not compared to the VOC emissions from all sources. In fact, while VOCs may contribute to ozone and warming affects, I'm not sure the term "toxic" is a particularly good fit. What does matter to me is true 2-year performance, which does minimize environmental impact.

    I hope the EPA focuses on life-cycle impact (toxicity/year) and not arbitrary formulation specifics. We'll see.