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Protect the Natural Dune Seawall - page 6 / 11

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collapse during wave attack. In extreme storms, the dunes erode back as much as 100 yards. Hurricane Carla which struck the coast at Port O’Conner in 1961, eroded the dunes back about 200 feet at Port Aransas, far to the south of where Carla went ashore. Parts of the coast with a poorly developed foredune ridge, well protected at the toe by vegetated coppice dunes can lose their entire dune system and then be subject to massive hurricane overwash which destroys virtually all man-made structures further inland. We just saw that happen in Katrina and Rita.

What is the Problem with Port Aransas Beach Management?

Port Aransas from Horace Caldwell Pier to the Aransas Princess Condominium has an unnaturally wide beach created by our beach management practices since Hurricane Allen eroded the dunes in 1980. Note how wide the beach is from the pier to the Aransas Princess (between the red arrows).

Since 1980, traffic has been forced by traffic barrier posts to drive very close to the toe of the dunes, where vast amounts of dry sand is naturally blown in from the lower beach and deposited by the wind. This is

the nursery

where critical

coppice dunes

naturally form.

road

graders

and

front

end

loaders,

the

critical

coppice

Between

the

removal

of

dunes

traffic

and

regular

the

loose

sand

by

have not been allowed to form and

grow the vegetated dune line Hurricane Allen back in 1980. dunes are born.

seaward to make up the loss in vegetated dunes eroded by In fact heavy machinery is destroying the nursery where infant

Shortly after Hurricane Allen, a new line of mile markers on high posts was installed along the beach. They are now buried in the high dune ridge facing the beach. If you look south of the Aransas Princess, the same line of mile markers is well inland, showing how much the critical coppice dunes have built the vegetated dunes seaward in the intervening period since Hurricane Allen. Also south of the beach where the traffic has been forced to drive up next to the dunes, you can see how much narrower the beach is. Our beach is not wide because it is newly

deposited

beach, it is

permitted

to form.

wide because the critical coppice dunes have been either destroyed or not This weakens our natural dune seawall and has some very serious

implications for our future ability to Remember, we will most definitely future. The only question is when.

withstand a pounding attack of hurricane surge and waves. be subject to direct attack by a major storm again in the

6

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