Environmental pros and cons of artificial reefing

[Jax]

How do they decide where to sink these things? Seems a bit of a waste to sink a ship where most of it is accessible only to tec divers.

 

[Teamcasa]

How do they decide where to sink these things? Seems a bit of a waste to sink a ship where most of it is accessible only to tec divers.

Fishermen also like a deep wreck.

 

[fire_diver]

they sink bridges and other stuff (army tanks, railway box-cars) - but they are not as much fun to dive on as an old warship.

I was under the impression that it was cheaper to reef an old warship than to scrap it (not sure where I heard that though), but does seem that all these reefing projects take many years and costs lots of $$ due to the red tape - must be a more economical way of doing it or streamlining the process.
For fishing and diving (and then related industries of hotels/restaurants etc) they are great for the local economies.

Sure there is. As you tow it to a new home to be cleaned, you accidentally scuttle in an area close to shore, that provides diveable depths, yet doesn't impede shipping lanes. :shocked2:

 

[Louie]

While there's general favourable reaction to artificial reefs, we also have to deal with resistance from certain segments of the community (for various reasons).

Here in BC, there is some resistance to a major artificial reef project - headed and orchestrated by a small group of residents living in the vicinity of the proposed sinking of a ship. They claim that a diveable reef would disrupt marine life and the presence of large numbers of divers would be a negative outcome for the residents.

Here is a blog on the matter: Geist in my machine Blog Archive When will the Annapolis sink?

And the Artificial Reef Society page: ARSBC: HMCS Annapolis

News coverage (TV) CTV British Columbia - Planned scuba-diving attraction irks Gambier residents - CTV News

While those who understand the values of artificial reefs may be irritated by the misinformation from the NIMBY lobby, they can be a disproportionately loud and influencial voice.

 

[gsk3]

As far as where they get sunk, my understanding is that there are generally clearance requirements to prevent a navigation hazard, so that the top cannot be more than e.g. 65 feet from the surface. That means that most big ships get sunk in 130+ feet of water. They are accessible to all, just not all of them is accessible. The Radnor which is being sunk off Delaware is having its mast removed so that the clearance restriction keeps the majority of the ship accessible to rec divers.

The issue for me is the ships the government currently owns just sit in mothballs until they sell them (for peanuts) to a private contractor that scraps them for a pretty decent profit and generally sends the scraps overseas.

Oftentimes the scrapping is done overseas in the enormous and horrible (on both humane and environmental levels) scrapyards.

 

[adambayam]

What kind of artificial reefs are you getting involved with?

Are we talking about moth-balled boats where there is little or no up-keep, or concrete blocks where you plant the corals and maintain them?

If you are sinking boats then as long as then are prepped correctly then the enviromental impacts should be negligible.

 

[sunkmail]

As far as where they get sunk, my understanding is that there are generally clearance requirements to prevent a navigation hazard, so that the top cannot be more than e.g. 65 feet from the surface. That means that most big ships get sunk in 130+ feet of water. They are accessible to all, just not all of them is accessible. The Radnor which is being sunk off Delaware is having its mast removed so that the clearance restriction keeps the majority of the ship accessible to rec divers.QUOTE]

Here in BC, the clearance needed is 30+ ft. below the lowest tide.
The Annapolis, mentioned above, has had it's radar tower removed, allowing the ship to be sunk in only 100 - 110ft, while still maintaining more than the 30ft min. depth.

In terms of environmental considerations, the biggest hassle is the boiler and engine rooms - all traces of Hydrocarbons have to be physically removed, or scrubbed clean. It's usually easier to remove than scrub - ie, piping, but the tanks are scrubbed. I've spent A LOT of time volunteering on the Annapolis and can confidently say we are taking all the clean-up measures seriously.

For costs, the price of steel isn't that great at the moment. You may think it would be worth it for teh scrape $$, but the costs of tearing the ship into small enough pieces has to be weighed against the return. Generators ad machinery, on the other hand, can be a good source of funding for a AR project. Selling pieces as-is, or taking them apart for the various Brass, copper, Aluminum, and other valuable metals is well worth it.

I am not a member or spokesperson for the ARSBC, just an enthusiastic volunteer.

For an interesting read of both sides of the argument, check out the ARSBC Position paper, written after the opposition published their position.

The ARSBC paper goes through each point made by the opposition, without missing a single one, so you can see both sides of the issue in a single document.

 

[burna]

I'm generally against them. We are better off energy wise recycling the metal (steel or aluminum) than sinking it and having it irreversibly lost. Other than diving, I don't see much utility for them. As far as enhancing fishing opportunities (if we really feel we need to do that) there are other less environmentally expensive opportunities.

I have to disagree with you there.

Watch this then decide if you think it is better to clean them up and sink as a reef or 'recycle' them.

The Ship Breakers - 60 Minutes - CBS News

 

[Scott L]

I am astounded at the lack of response on this question. There are threads that go on endlessly about wanting to see a tank explode, MOF vs NMOF, DIR, etc., etc., yet almost no one has an opinion on this issue???

Most of the regulars were no doubt embroidered in another training agency or deep air squabble.

But seriously, I have a great interest in this subject living in an area which has created the Osborne Reef consisting of 1M+ discarded tires, a Rolls Royce and other such nonsense. Whenever a similar thread has been started in the past, the owner of this company generally chimes in with these products.

Reef Ball Foundation: Getting Grants For Your Project

I have posed the question of why purpose built larger interlocking modular concrete and steel systems cannot be produced which can better mimic the structure of real coral reefs and perhaps remain in place for perpetuity. However, several posters involved with these projects indicate the costs would be well outside the financial resources available. Any thoughts on the matter though?

 

[dumpsterDiver]

I can comment on the situation from my personal south Florida perspective. The wrecks are a very beneficial resource. They attact fish and divers and the more divers that visit a ship wreck, the less divers are available to impact the natural reef communities.

I have repeatedly seen the same mistake being made in Palm Beach County with shipwreck deployment and that is that ships are sunk with very little cover for bait fish. We have large intact ships in deep water that are typically very sparsly populated by benthic fish because there is too little habitat provided for "the small stuff" (bait fish and juveniles). A natral reef has many small nooks and cranies and dead end caves (or ones with smal openings at the back) that provide protection and are heavily utilized. Often when a ship is sunk there is a giant open waste land of flat deck space which provides no cover and very little useful habitat

Often these ships provide very limited benefit until they really start to get ripped apart ny huricanes, THEN they are much better.

I have complained about this several times to the local agency repsonsible for deployment of the wrecks and they often seem to ignore this issue. What I would like to see, is that the open holds of the ship are filled with large piece of concrete pipe, poles, large boulders etc to a depth of at least 3-6 feet, with some variability in height and distribution. The more small scale benthic diversity the reef can provide, the more attractive it will be and the more it will simulate a natural reef.

We see these large ships sunk in deep water and they seem to serve as FADS and aggregate pelagics (sometimes in good numbers) but the benthic population is pretty sparse.

The authorities have complained that they are worried about the seaworthiness of the vessels prior to sinking, but a few feet of rubble, boulders, concrete, even steel beams is nothing compared to the weight of typical cargo that is stacked 30 to 100 feet high inside a freighter. Even if the ship tips over and dumps the cargo during the sinking, I don't see a huge down side to having this clean material deployed in the immediate proximity of the ship.

I suspect people will say the ship "looks" like a junk yard if you pack it with this "refuse" prior to sinking, but once underwater it will function much better.