Save $$$ and be Green with . . . Oysters?
Almost. Almost! After writing this brilliant little article, I did my usual fact check and discovered, much to my chagrin, that I couldn’t in good conscience promote the use of oyster shells as a safe building material. According to the South Carolina Department of Natural Resources, oyster shells need to be returned to the sea after the oyster roast. Oysters apparently develop in “reef” fashion growing off of existing oyster shells. Young oysters must attach to a hard substrate, ideally another oyster shell, to develop. If no suitable substrate exists, the oyster dies. Hence, the “cluster.” According to the DNR, oysters act as little environmental ambassadors by helping the environment in the following ways:
- Filtering (adult oysters filter up to 2.5 gallons of water per hour, improving water quality in the process)
- Providing habitat (oysters build reefs, which provide habitat for fish, shrimp, crabs, and other animals)
- Controlling erosion (oyster reefs are natural breakwaters that protect shorelines).
So, for the time being, I’ll recycle my oyster shells at one of the many local shell recycling centers conveniently provided by the DNR. (Go to http://saltwaterfishing.sc.gov/oyster.html for recycling locations. They will even pick them up for you if you have large quantities.) Were it not for South Carolina marine biologists doing such a fantastic job researching and taking measures to preserve ocean life, the following article would hold merit and be able to be published. Due to a procrastinated fact check on my part however, I must leave it sitting here unpublished on this lonely blog. Here it is; the invalidated article. Read and devour.
Shuck an oyster and save $. Shuck an oyster and save the coast. Oysters are a fantastic building material and paving alternative. Let’s start with the driveway. You have the option of paving the entrance to a new subdivision, or a driveway, or a boat landing, with asphalt or with oyster shells. Asphalt will cost thousands of dollars. Oysters are free. So there, you just saved thousands. That was easy. And which is more beautiful to come home to? Black/grey asphalt, or crushed, pearly white oysters? Well that’s easy to answer as well. So how does using oysters as opposed to concrete and asphalt protect the fish habitat in our area? How does this protect the water quality of the creeks, harbor, and ocean? How does this counter global warming and the amount of carbon dioxide put in the air? Can “paving” with oysters really do all of that? Yes! First, let’s take a look at what’s involved in the production of concrete.
“Embodied energy” can be defined as “the amount of non-renewable energy used in the production of a material, from the acquisition of natural resources to product delivery.” As far a building materials go, concrete is pretty high up on the list of using the most embodied energy. In order to produce concrete; tons of sand, cement, and crushed stone have to be shipped to a mixing facility. Before they can be shipped, the stone must be crushed, the sand harvested, the cement made, and water piped in. So we’ve already burnt a lot of fossil fuels before we even make it to the plant to make the concrete. Now we have to use more electricity (which means burning more coal) to weigh, mix, create the concrete. Now we have to ship it wherever it’s going. In a nut shell, the amount of CO2 put in the air by concrete production is exceptionally high.
Now let’s look at the embodied energy in oysters as a building material. Well, this is going to be a short paragraph. I guess a few gallons of gas have to be used to go out in the boat and throw them in the truck and deliver them to the party. But we were going to do that anyway right? It’s more a matter of recycling those oyster shells. So we can’t even honestly include those few gallons of gas in our survey of embodied energy.
So what happens once the road or driveway has already been built? We’ve all heard of “stormwater management,” but what exactly is it and how does it work? In order to save you, the reader, from doing infinite research on this topic and trying to understand it, I’ll cliff note for you here. After a good rain, storm water runs off of concrete and asphalt roads, parking lots, driveways, and all impervious surfaces into creeks, the harbor, and the ocean. In this process, the water carries with it human pollutants (oil, pesticides, pet waste, plastics, etc.) that have been deposited on these surfaces by every day human use. The pollutants are carried into the creeks, rivers, ocean, and move their way through the food chain ending up the fish. This storm water run off also causes the erosion of creek and river systems and causes flooding. This “stormwater” is “fresh water,” which rapidly desalinates the rivers and the harbor. Oyster beds near urban areas are often closed after approximately ½ inch of rain due to being saturated with pollutants. Ever go shrimping after a good rain? Probably not; because if you are a shrimper then you most likely already know that you’re not going to catch anything after the fresh water has inundated the shrimp territory. The shrimp and other fish swim like mad to the deeper, saltier waters.
Imagine that all of the domestic roads and driveways in Charleston were “paved” with oyster shells. The storm water and pollutants would be absorbed into the ground beneath the oysters. The harbor and rivers would be much cleaner and freer of pollutants. The fish would be more abundant and safer to eat. The amount of mercury going into the air, the water, and the fish would be significantly reduced (the mercury comes from the coal fired power used to produce the electricity to make the concrete. Almost all of Charleston’s electricity comes from coal.) And a dent in CO2 emissions would be made. What a beautiful solution! Almost! Almost! If not for the facts. For now, we must recycle our oysters at one of the locations listed on the DNR web site so that they can be used to spawn the creation of more oysters. As one my teenage students used to say when reprimanded for cursing, “Well Pooots!”
Here you can find a list of places where you can recycle your oyster shells. http://saltwaterfishing.sc.gov/oyster.html. This site gives you a lot of great information about recycling oysters in general. You can also read about concrete production and more at www.buildinggreen.com.
Now go shuck some oysters!