Resources / Our Blog / Copper Bottom Paint and TMDL’s in MDR
By admin on April 17, 2014
Copper Bottom Paint and TMDL’s in MDR
Recently, copper bottom paint has become the hot issue in Marina del Rey. We at the BoatYard understand that this is a very complicated matter which is of tremendous importance to the boating community. In order to to help improve clarity and act as a source of information we have created this blog. We are also hopeful that this will become a good source for airing differing opinions and a as method for reaching out to those most knowledgeable on the topic.
Bio-fouling, especially of ships, has been a problem for as long as mankind has been sailing the
oceans. Techniques of using pitch and copper plating as anti-fouling methods are attributed to the
ancient seafaring nations such as the Carthaginians and Phoenicians as far back as 1500-300BC.
Later on the Royal Navy from about 1770 set about coppering the bottoms of the entire fleet which
continued until the end of wooden hull ships. The process was so successful that the term “copperbottomed”
came to mean something that was highly dependable or risk free.
With the rise of iron hulled ships copper could no longer be attached to the ship’s hull due to
galvanic corrosion issues so copper containing paints were developed. By the mid twentieth
century, copper oxide based paints could keep a ship out of dry dock for 12-18 months. By the
1960’s there came advancements in paint technologies which allowed the copper biocide to leach
slowly from the paint and provide longer protection. What followed were several decades of using
stronger and more deadly biocides such as tributylin tin oxide (TBT) which was among the most toxic
pollutants ever released into the ocean. These paints could last as long as five years or more before
a haul-out would be required.
As an alternative to these highly toxic biocides a renewed interest in copper as the active agent in ablative or self-polishing paints brought about the modern bottom paints widely used today on 90%
of the vessels in the world. When first introduced, copper bottom paints were hailed by the
environmental community as the environmentally safe and effective alternative. For several
decades, copper bottom paints have been the choice of boaters for reliable and cost effective
As we look forward, there are promising new technologies such as using natural biocides, ultrasonic
energy waves, and nanotechnology but currently, there are very few alternatives which even come
close to the effectiveness and time tested acceptance of copper as an anti-fouling biocide. Other
metal biocides such as zinc based paints are now on the market and although early testing is
positive, concerns remain that simply moving to another metal biocide is only kicking the can down
the road. Paints containing natural biocides such as Econea are also very promising, however,
approval for use in California is still being pursued by the manufacturers. Long term studies on
Econea also need to be done in order to confirm its effectiveness in the real world.
The Cure in Search of a Problem
Back in 2006, the California Regional Water Quality Control Board (“CA RWQCB”), Los Angeles
Region put into effect certain standards for what it considered sufficiently clean water as dictated by
the Federal Clean Water Act for Marina del Rey. In accordance with these standards, Marina del Rey
Harbor is identified as an “Impaired Waterway” for containing chlordane, copper, lead, zinc, PCBs,
DDT, and other substances. On November 5, 2013 a subsequent report released by the CA RWQCB
entitled “Reconsideration of the Maximum Daily Load for Toxic Pollutants in Marina del Rey Harbor”
seeks to increase the scope and finalize the recommendations from the 2006 report. This report
was the subject of a RWQCB hearing on February 6, 2014 in Los Angeles and was of great concern to
boaters, Lessees, and the County of Los Angeles as it may burden all of these stakeholders with long
term clean-up responsibilities. Approximately 200 interested parties showed up for this hearing
and testified in opposition to the plan including the LA County and Sen. Ted Lieu’s office.
The Problem Statement in the CA RWQCB report states that Copper and other pollutants affect the
beneficial use of Marina del Rey for: 1) Water Contact Recreation, 2) Marine Habitat, 3) Wildlife
Habitat, 4) Commercial and Sport Fishing, and 5) Shellfish Harvesting. Notwithstanding the fact that
swimming, fishing, and shellfish harvesting are prohibited in Marina del Rey, the impact on these
uses is still considered a problem because we are told they “could be” potential uses.
For the purposes of this discussion, I will focus on copper as it relates to bottom paints widely used
in the local recreational boating community. All of these regulated substances, however, must be
dealt with rationally and by using the best available science and through the involvement of the
broadest stakeholder group possible. In addition, unless a practical and measured approach is taken,
severe socio-economic impacts to the boating community in terms of loss of recreation, decline in
business, and un-intended environmental damage will occur. These impacts, particularly on
recreational uses could eclipse any benefits which might be realized by the overprotection from
these substances if not implemented properly. Careful consideration must be given to utilizing a
measured approach such as allowing natural degradation, algae biosorption, and low copper bottom
paints to reach more realistic TMDL goals over rational time periods.
As far as copper is concerned, the RWQCB standard is set at 3.1 ug/L (micro grams per liter) for the
water column. The problem is that there is quite a bit of controversy as to whether this standard is
the correct one to use. Without getting overly technical, the toxicity of copper is directly related to
how much is available to an organism; this is called bio-availability. At low levels, copper is a
necessary element for healthy organisms, however, at too high a concentration it becomes toxic.
Where things get tricky is that whereas bio-availability is simple to determine in clean freshwater, it
becomes more difficult to determine in sea water unless site-specific data is taken into
consideration. What happens is that when released from the bottom paint, the toxic cupric ion
(Cu+2) quickly binds with nearby substances to form inert, non-toxic compounds. When this
happens, the bio-availability or toxicity of the copper is greatly reduced even though the total
dissolved copper is high. As a result, the copper containing bottom paint performs its desired effect
as a pesticide in close proximity to the boat’s hull but then quickly becomes non-toxic as it falls
Marine chemists have addressed this problem for several years and have developed what is known
as the Biotic Ligand Model (BLM) which takes site-specific factors into consideration. Although the
EPA recognizes this method, it has not been adopted for saltwater marinas. Many scientists and
organizations including representatives with the California Department of Pesticide Regulation (“CA
DPR”) believe that the 3.1ug/L standard may be overprotective when site-specific data is not
considered. In its June 2009 report entitled “Monitoring for Indicators of Antifouling Paint Pollution
in California Marinas” the CA DPR suggests that a concentration of between 6.0 and 9.4 ug/L (as
opposed to 3.1 ug/L) may be more appropriate depending upon the length of time organisms are
exposed. In addition, from a biological perspective, copper impacts on living organisms have been
predominantly studied with the common mussel known as Mytilus edulis which according to Dr.
D.J.H. Phillips at the University of Melbourne “should not be used as an indicator of copper in the
marine environment”. He states that “In contrast to other metals, the net uptake of copper by the
mussel was extremely erratic, and was affected by salinity and temperature changes and by the
presence of other metals…” In fact, very little data on real world effects on any species in Marina
del Rey exists, making the Impaired Waterway designation for copper mainly theoretical.
As set forth in the recently published LA RWQCB boater hand-out, “The proposed plan allots 11
years to reduce copper discharge from boats by 85%. This plan is one step in a process to gradually
reduce copper in the harbor waters. The plan can be amended based on new findings and goodfaith
efforts towards improving water quality”. In addition, the Board suggests there are several
options on how to achieve this including switching from copper-based bottom paints to non-toxic
antifouling paints, use of slip liners, and the use of less abrasive hull cleaning techniques. It is our
experience that slip liners are of very limited use as they only work well on small vessels and are
often used with high doses of chlorine or other biocide which is then released into the harbor when
the vessel is re-launched. In addition, slip liners only transfer marine growth from the hull to the
bottom of the liner, which then also must be cleaned. The adoption of less abrasive cleaning
techniques especially through training and licensure for bottom cleaners should be able to yield
immediate results and I agree makes a lot of sense. Switching from copper to non-toxic antifouling
agents sounds great, but what are these non-toxic paints and do they really work?
Alternatives to high-copper bottom paints fall into three basic categories: 1) Non-biocide, 2)
Alternative biocide, or 3) Low copper biocide.
- Non-biocide paints work by creating either an ultra-slippery surface from which organism may be easily removed, or ultra-hard bottom paints which can be aggressively scrubbed without releasing toxins. The slippery paint finishes are silicone based products that work well for faster moving boats which are used frequently. These surfaces are very soft and are easily damaged by over-cleaning or if hit or scratched. Once the paint surface is damaged marine growth occurs rampantly on unprotected areas. These finishes normally have a relatively short effective life span of around 8-12 months, and are extremely expensive (typically three times more than traditional bottom paint). They cannot be applied over old copper containing paints and therefore an expensive hull stripping is required. Some boat yards refrain from hauling out 4 | P a g e boats with silicon bottom finishes as they are so slippery they can easily slid out of the Marine Travel Lift straps. The harder surface paints do no deter growth and must be aggressively cleaned weekly and are primarily used for sailboat racing bottoms on vessels which are removed from the water for storage. Aggressive underwater cleaning will also be more expensive and frequent, especially during the summer season.
- Alternative biocide paints include paints based on other metals such as zinc or those utilizing non-metal biocides such as Econea. As previously stated, there is no sense moving to alternative metals since this only reduces copper by elevating another metal which hasn’t yet been studied in Marina del Rey. Nonmetal biocides show great promise although Econea is currently not approved for use in California by the CA DPR, and the long term effects of Econea require further study. Although slightly more expensive than copper bottom paints, Econea based paints appear to be very effective and new formulations such as Hydrocoat Eco may be applied over copper painted bottoms without stripping.
- Low copper bottom paints typically contain about a third to a half the amount of copper found in the paints used today and some utilize Econea or other co-biocides as well. With good hull cleaning techniques, these paints can last just as long as regular copper paints and have an immediate effect on the amount of copper leeched into the water column. They are also the most cost effective and do not required hull stripping for use.
The following table lists several paints manufactured by Petit Paint Company and used by the BoatYard in Marina del Rey along with their individual properties and approximate retail costs:
It is my opinion that paints such as the low-copper Vivid, Hydrocoat, Hydrocoat SR, Ultima SR and
the copper free Hydrocoat Eco and Ultima Eco represent the most effective alternatives to the
standard high copper paints commonly used today which contain as much a 70% copper. These
paints are highly effective in reducing growth, are cost effective, and will significantly reduce copper
loading in Marina del Rey over time. Since they are generally accepted by the boating community
and some don’t require stripping, a more rapid implementation and achievement of copper
reduction goals will be possible as compared with less disruption to the boating community.
One last word on alternative paints; don’t buy snake oil! As can be expected, many early and
untested products have made their way to the market with claims that seem too good to be true.
Although we do not intend on throwing any specific products under the bus, claims of 4 ounces of
product covering an entire 40 foot boat and lasting for ten years, well, sounds too good to be true.
There are only a couple of large companies that have a long history and commitment to
manufacturing bottom paints in the quantities needed by the boating public. Many small start-ups
may not have the ability to put their products to the rigorous testing needed to gain boater
confidence. In addition, boat yards will be very reluctant to use untested products as their
customers will hold them responsible for poorly performing bottom paints with short useful lives.
Three Legs of a Stool
In order for any copper reduction approach to work in the real world it will have to have three legs,
and like a three legged stool, will fall over if any of the legs are removed. They are:
- Effective Alternatives: The Product or alternative to copper based paints must be proven to
work in the real world.
- Boater Buy-In: The boaters must believe that they are doing the right thing for the environment
supported by good science and achievable goals.
- Cost Effective: The alternative must be cost effective and not priced out of the boating public’s
Since the increased cost in stripping a 35-foot boat and applying a non-toxic biocide over a new
barrier coat will cost four or five times the cost of a normal haul-out ($8,000 vs. $2,000) and have a
shorter useful life, grants have been proposed as a means to incentivize the boater to switch over.
These grants have been tried in San Diego and Newport Beach and have largely failed to attract
many takers even though they claim to be easy to obtain and cover about 75% of the costs. I
believe the main reason for this is as stated above, the third leg fell off since there was little boater
buy-in and limited effective alternatives. In fact, it has been reported that most boaters who
switched to a non-biocide paint switched back to copper at their next haul-out.
Enforcement Challenges and Economic Impacts
Perhaps one of the biggest challenges of the proposed plan will be in its enforcement, especially
since marinas and boat yards neighboring Marina del Rey will be exempt from this plan. While it
would be relatively easy to have boaters adopt low copper or alternative biocide paints it is unlikely
many boaters will voluntarily switch to non-biocide paints. Enforcement then would be necessary
against the individual boater through either a requirement to have special documentation or
through the use of testing. Fines and additional regulation and maintenance costs will undoubtedly
reduce the attractiveness to boating in Marina del Rey as compared to surrounding marinas or
alternative recreational choices. Vessels will be likely to leave for less expensive marinas resulting in
substantial rent loss to the County of Los Angeles as well as the trickle down effects on local
businesses such as restaurants, retail stores, residential apartments, marinas and boat yards.
As an avid boater and owner and operator of two southern California boat yards “The BoatYardMDR”
and “The BoatYard-Channel Islands” I would like to make an appeal for a more reasonable
approach to the copper problem.
First, more study is needed to see if site-specific conditions dictate a higher threshold for a copper
TMDL through the adoption of the Biotic-Ligand Model,
Second, benthic studies and bioassay of indicator species must be done in order to determine real
world impacts in Marina del Rey and the “one size fits all” TMDL needs to be re-thought,
Third, consideration should be given to the fact that some marinas due to their unique man-made
origins are not naturally flushed, and for that matter are not even natural. Somehow the idea that
the waterway is impaired especially when its use is restricted as a small craft harbor with fishing,
swimming, and shell-fishing banned, seems over-protective. Oddly, the best protected harbors that
have the least flushing will bear the brunt of this plan while well flushed harbors will be allowed to
go on releasing even greater amounts of toxins into the ocean.
Fourth, a bigger picture environmental review must be made in order to balance the benefits of
reduced copper in the harbor with the unintended environmental and socio-economic impacts.
Stripping and disposing of copper containing bottom paints along with the huge carbon footprint
associated with this clean-up will create other impacts somewhere else which aren’t being
considered. An even greater environmental impact will be created should the proposed dredging of
the entire harbor be enacted. The chilling image of tens of thousands of trucks transporting dredge
material over public streets to far off dump sites, for many years is indeed sobering,
Fifth, the TMDL Reconsideration document is extremely technical and full of information which has
been studied for a long time by the Board. Giving the only forty-five days (45) for public comment is
completely insufficient for an adequate review of such a complex document, especially when
released right before the Thanksgiving and Chanukah holidays and due four (4) days before
Christmas day. Given the scientific complexity of the issue a more reasonable time for public review
and scientific analysis was in order, and
Last, and most importantly, a more measured approach to copper reduction should be pursued
including the utilization of low copper and alternative biocide paints over a longer adoption period
of about twenty years. This will also allow time for the development of new paint technologies and
natural attenuation processes to occur.
Note on Author: Gregory F. Schem holds a degree in Chemistry from the State University of New York and
a Masters in Business from Cornell University. He has been in the marina and boat yard business for
fifteen years and is a lifetime boater. He served for three years on the Governor’s Blue Ribbon Task Force
for the California Marine Life Protection Act, is a member of the Association of Marina Industries, Marina
Recreation Association, and the American Boat and Yacht Counsel. Mr. Schem holds a 100-ton USCG
Master Captain License, is a certified SCUBA diver, and an instrument rated private pilot.