Plastic Shrink-Wrapping Boats for Winter Storage – Adverse Effects on Environment

Plastic shrink-wrap on a plastic kayak…really? (see photo). When people start covering cheap-plastic with more plastic, it’s surely a sign that shrink-wrapping is getting out of hand!  

UNBELIEVABLE!?  Plastic shrink-wrap winter storage layer over a cheap, plastic recreational kayak (“banana-boat” type kayak).   What a waste….  (City of Rye NY Municipal Boat Basin, March 26, 2020)

Covering boats with heat-shrink LDPE (low-density polyethylene) film for winter storage has caught on quickly in recent years – now it seems every boat in the marina is shrink-wrapped. The mountain of plastic waste this generates every season is scandalous. But is shrink-wrapping boats for winter storage even necessary?  I did a little research on the topic and consolidated what I found below.

1    1. The Problem:

The overarching problem of plastic waste is a huge issue having larger societal and ecological consequences.  This blog post here is focused solely on the issue of boat shrink-wrap plastic.  At present, most of this shrink-wrap material is sent to landfills or is incinerated. It is made from LDPE, combined with additives to provide UV resistance and other properties. As discussed below, very little of this material is recycled. The average boat requires 15 lbs of shrink-wrap each season, multiplied by the 13 million registered boats in the United States it’s easy to see how disposal of shrink wrap could cause a landfill crisis. (1)  Incineration of LDPE and other plastics causes its own problems – principally the release of heavy metals, organic pollutants, and other toxins into the air and in incinerator ash residue, which itself must be landfilled. (2) And lastly, plastic constitutes the predominant form of marine debris. (3)  As kayakers, we all see more and more plastic (including boat-wrap) littering the shores.

 2. Is Shrink-Wrapping Boats Even Necessary?:

Retailers and manufacturers of boat shrink-wrap say the protective film is necessary to keep rain/snow out of your boat and to minimize UV sun damage when the boat is in storage for the winter. If you dig deeper though, you’ll find that this isn’t the whole story.

Firstly, the cost of wrapping your boat annually is not cheap. I’ve seen local prices range from $15-25 per foot – starting at $450 flat rate for boats 25’ or under. That’s every year.  By comparison, a well-maintained canvas cover can last 20 years and many are made from cotton duck fabric so are ultimately biodegradable. Though more expensive to purchase initially (roughly 2x/3x cost of disposable LDPE wrap), the extra up-front cost of a canvas boat cover can be quickly recouped in just a few years. (4, 5)

After reading many online sources, it appears shrink-wrapping your boat may actually be worse than doing nothing when it comes to mold. The sun’s radiation will heat up any water trapped on/in the boat beneath the plastic wrap cover.  Temperatures under the cover will swing up by day causing evaporation (increased humidity) and drop down at night causing condensation. The result – MOLD. Now you’ve got another problem so must use fungicides or other mold-preventives (sprays, heaters, desiccants, etc.). (6)    Alternatives, like keeping a boat under a more open/breathable cover (like canvas) or under the roof of a garage can provide more air-flow and prevent humidity and mold problems.

Another alternative to shrink-wrap is to have no cover at all. (How's that for a concept). UV damage can be minimized by spraying a UV protectant (303 etc.) on rubber parts a few times in the off-season and by applying a protective coating of wax on the hull before storage. If that’s too much work, then do nothing – wait until the boat's finish fades then polish/restore any oxidized gelcoat once every 20 years – remember, gelcoat has UV inhibitors in it so resists oxidation!   Isn’t restoring a boat hull with some polish and a power buffer once every 20 years a better solution than adding 300 lbs of plastic waste to landfills (15 lbs/year x 20 years)?

3      3. Recycling:

While better than landfilling, recycling LDPE shrink wrap is a mixed bag.

The EPA estimates that only 6.2% of LDPE (recycling number 4) is recycled in the United States. (7) That’s for LDPE overall – most of which is the rigid kind, used in food containers, etc. The plastic film type of LDPE is the material used in plastic grocery bags and is also the class of plastic used for shrink-wrap boat covers. Recycling of these thin, flexible LDPE films presents added difficulties over the more rigid type. These films must be separated from the general plastic recycling waste stream because they require special machines that will not become clogged during the milling process. Also, LDPE films are often contaminated (dirty) and must be cleaned before they can be recycled, adding  time and energy to the process, and accounting for the very low percentage of LDPE recycling worldwide. (8) 

Even if recycled, LDPE plastic is not “closed-loop” recycling. That is, it cannot be recycled into the same product, over and over. It is “recycled”, or more accurately “converted”, into a different final-use product, like composite lumber or carpet material. (9) This is partly due to the additives in plastic – UV inhibitors, flame retardants, coloring agents, etc. – that act as contaminants and prevent it from being reused in the same form.  Also, plastic can only be recycled a few times before its quality decreases to the point where it can no longer be used. Typically additional virgin material is added during the recycling process in order to “upgrade” the quality of the plastic. (10, 11)  

By comparison, aluminum and glass are “closed-loop” recyclable materials – they can be made over-and-over into new bottles and cans without losing quality or purity. Unlike plastic recycling, there’s no need to add virgin material in the glass/aluminum recycling process. (12)  As an aside, I’ve personally tried to eliminate all single-use plastic – bottles, bags, cutlery, etc. – and only use aluminum cans when buying beverages and fabric grocery bags when shopping, surprisingly easy things to do.

At present the cost of boat shrink-wrap disposal is largely borne by taxpayers in the form of garbage hauling, landfilling, etc. While some businesses offer prepaid shipping bags that can be used to send boat shrink wrap in the mail for recycling (“Dr. Shrink” sells a prepaid shipping bag for $50), a marina-based collection/hauling operation is clearly preferred to reduce costs and to avoid the need for additional materials to wrap/mail the waste! (4, 13)  Westchester County’s Boat Wrap Recycling program collects boat-wrap if your marina participates. (14)  Now, whether “recycled” boat wrap plastic is ultimately processed into recycled products depends on the status of the world’s recycling market at the time it is collected.  If the market is uneconomical (as it is now for many plastics), this material will be landfilled or burned... (15)  Some have advocated for an upfront “product stewardship” deposit to address the full cost of plastic boat wrap over its life cycle, thereby shifting recycling costs from municipalities to the consumers who directly benefit from the product. No such regulations currently exist in New York that I’m aware of.

So that’s it – something to think about and something for boaters to work towards eliminating if possible.  It should be noted that many kayaks are also made from LDPE and should also be recycled when their useful life has ended. And perhaps old fiberglass boats can be milled into fibers and reused.  In my view, the difference between the plastic/fiberglass material used to make boats themselves and the plastic shrink-wrap used to cover them is that shrink-wrap covers are essentially single-use items for which there are alternatives. 

For more - check out this recent PBS documentary, Frontline: Plastic Wars, which delves into the conundrum of recycling plastic:  https://www.pbs.org/wgbh/frontline/film/plastic-wars/

References:

1: https://www.boattrader.com/resources/shrink-wrap-recycling-easier-think/
2: http://theconversation.com/why-municipal-waste-to-energy-incineration-is-not-the-answer-to-nzs-plastic-waste-crisis-126824

3: https://www.no-burn.org/burning-plastic-incineration-causes-air-pollution-dioxin-emissions-cost-overruns/

4: https://www.seacoastonline.com/article/20140514/OPINION/405140366

5: http://www.fishercanvas.com/aboutus.asp#armyduck

6: https://tomdwelsh.com/2015/10/08/shrink-wrap-boat-storage-dangers-and-long-term-effects/

7: https://millerrecycling.com/ldpe-out-of-landfills

8: https://www.plasticexpert.co.uk/plastic-recycling/ldpe-recycling-plastic/

9: https://www.dec.ny.gov/chemical/8817.html

10: https://www.newenglandshrinkwrap.com/SW%20Recycling%20Guide%201.pdf

11: https://www.sciencedirect.com/science/article/pii/S030438941730763X

12: https://blog.nationalgeographic.org/2018/04/04/7-things-you-didnt-know-about-plastic-and-recycling/

13: https://operationsplash.org/2010/04/03/growing-problem-of-shrink-wrap/

14: https://www.pressherald.com/2017/08/20/to-protect-them-from-the-elements-many-maine-boats-are-shrink-wrapped-in-plastic-for-the-winter/

15: https://environment.westchestergov.com/residents/212-news-events/2582-boat-wrap-recycling-expands-to-hudson