The Tribune

YOUR SAY

By BILL MARDELMEIER

TODAY, headlines tell us that Florida is running out of sand. Just reading about it in print has probably caused the hair on the neck of many Bahamians to rise in apprehension and fear.

It will almost certainly have caused local environmental protectors to be on guard against anyone who even thinks of messing with our sand.

Most people know that sandy beaches so vital to a healthy tourism trade move in reaction to powerful storms. The sand moves directly offshore a short distance and it may move parallel to the shoreline in response to a wind vector pushing it along.

With the return of calm weather, the large portion that moved offshore will slowly return. Some fraction that moved laterally may fall into the deep and not be retrieved easily.

The entire US East coast is a long conveyor belt moving sand southward. When it intercepts a deep harbour access channel sand drops off the conveyor; then upon the far side it must start to pick up a fresh load to carry southward.

Florida has for many years lived with the occasional but recurring need to replenish tourist beaches when it would take too long for nature to move it all shoreward. They have used dredging techniques to speed-up beach replenishment by pumping it back onshore.

However, over a period of 50 years or more a sizeable fraction escapes by dissipating into the deep. The accumulated factional losses of 50 years suddenly become a serious problem. It may demand bringing in new sand.

Today’s problem in Florida is not a sudden surprise. Beach geologists have long been fully aware of the accumulating “shortage” of sand.

Floridians can solve it by trucking sand from ancient small deposits inland but the cost of trucking (or railing) today is very high. (ie sand has taken on a much greater monetary value)

They may have very small sand producing “factories” along their coast but the output is small compared to ours.

The Bahamas has one of the worlds largest most efficient sand-producing “factories”. Nature produces new sand by precipitation on almost every tide in certain parts of our archipelago.

The writer tried to gain an estimate of how much new sand we produce in a year by contacting very learned souls at Florida’s prestigious School Of Marine Sciences some years ago. I was surprised to find neither the weight nor volume of new production is published in literature and perhaps not really even established.

What we do have are reasonable estimates of how much lies in our “storage” areas.

Most of it reposes in about five or six specific areas where it has accumulated here over the ages. Historically we used only a tiny bit that was close at hand to build our structures and cities.

That “tiny bit” was enough to exhaust very localised sand banks near population centres. The result is that our remote storage areas contain many billions of tons of sand.

Only a very tiny portion of this total reposes on our beautiful beaches, developed and undeveloped. That small fraction is of inestimable value to our economy and to our happy well being.

Much of the world’s sand is manufactured by nature bashing stones against rock in a slow aggregation often containing a fair amount of quartz and silicon. Microscopically it usually has very sharp edges where it fractured while travelling along its historic path from large rock to grain of sand.

Sharp edge is often a very desirable characteristic. In my younger era while operating and chartering large tankers and bulk carriers, one charter that I concluded astounded me at the time.

It was to move a large shipload of sand from Belgium to Honolulu. After the first cement plant was built in Hawaii it was found that local sand did not have the sharp edge nor brittle strength needed for high strength concrete. The temporary answer was to blend-in some Belgian glass sand.

Our sand too is not sharp edged. It is primarily constituted of calcium, with small fractions of other elements configured in an egg-shaped particle.

The reason is that our sand is chemically manufactured in the shallow seas edging our deep waters. Tiny skeletons of ocean plankton rise upward through deep warming seawater grabbing carbon dioxide molecules that build in layers like a hailstone before flowing on a flood tide onto warm shallow banks/edges.

The hailstone soon becomes too heavy to be carried further and is dropped off in sand banks a short distance from its deep water origin.

If nature does this for many thousands of years it will result in the billions of tons of sand in our big deposits.

Only a fraction of our 300,000 residents have laid direct eye on these deposits. They are not near our main population centres.

Sand is so vital to our economy that we dare not jeopardise its relationship to tourism or to our own recreational pleasure.

However if we were to dispose of 10 million tons per year it would take a thousand years to “run out”.

That does not consider the many additional tons we might “manufacture” each intervening future year.

Certainly we must protect the inheritance of our great, great grand children’s grandchildren, but before their era arrives we are told that many of our assets will likely have already disappeared beneath the sea. At that point what will be the value of sand?

It was about 35 years ago that local Nassau consumption had nearly exhausted the supply of sand in the neighbourhood of Rose Island Rocks.

We also now know that all parts of the shorelines near New Providence can be directly impacted by tampering with any one sector (a point of much publicised local contention today at our western tip). That may not be pertinent in many remote parts of the country but it probably is equally true with respect to the beaches of our major outlying islands.

Bahamians will not easily accept the possibility that the day will come when Bahamian sand in large quantities will be sold at very high price to foreign buyers. I am not promoting it, but in my opinion it will happen.

The tiny island of Nauru in the mid-Pacific was blessed with a vast quantity of phosphate from bird guano. For decades the phosphate was mined and the islanders were affluent until the land was almost gone and the island was virtually a hollow shell with a garden perimeter.

Thirtyish years ago Nauruvians had substantial wealth but there was little left worthy of investment at home so they unwisely invested and squandered their wealth in a series of tragic missteps.

Both sand and oil could prove to be “black holes” for our resource wealth unless we lock-in early planning that will preclude squandering, and with transparency, prevent corruption.

We must proceed with caution and total transparency if we are to enjoy the benefits of our natural resources. How do we make that possible? Norway seems to have accomplished preservation of assets for its future offspring. Can we also do it?

On the other hand, when Wall Street is 15 feet deep in rising water will we sit in a rowboat and reminisce about that huge amount of sand we abandoned down there near 25 degrees north and 77 degrees west?”

Reference:

BEACH NOURISHMENT AND PROTECTION, National Research Council-1995

WAVES AND BEACHES , Willard Bascomb