Page 1 of 1

Erosion experience question

Posted: Fri Jul 04, 2014 6:43 pm
by loco4viento
Hi everyone,

I'm wondering if any of you have any successful experiences with anti-erosion measures in areas where longshore (side shore) currents are a significant contributor to sand dune coastal erosion. Have any of you seen successful measures which have resulted in actual sand deposition and restoration of beaches? I'm less interested in periodic beach nourishment and more interested in other strategies that may have been successful in areas that any of you might know.

Thanks,

John

Re: Erosion experience question

Posted: Fri Jul 04, 2014 11:01 pm
by BiteMe
Not sure about the sand deposition and restoration, but I have seen where rock jetties help with erosion issues.

Re: Erosion experience question

Posted: Sat Jul 05, 2014 5:16 am
by acctx
loco4viento wrote:Hi everyone,

I'm wondering if any of you have any successful experiences with anti-erosion measures in areas where longshore (side shore) currents are a significant contributor to sand dune coastal erosion. Have any of you seen successful measures which have resulted in actual sand deposition and restoration of beaches? I'm less interested in periodic beach nourishment and more interested in other strategies that may have been successful in areas that any of you might know.

Thanks,

John
Jetties work, but they cause erosion on the "downstream" side of the jetty.

Sand socks do not work and make things worse. The water carrying the sand hits the socks and reflects back causing erosion. Some of the things that do work are the things that are a matrix that catches the fast moving sand as it comes on shore and slopes up causing the sand to be deposited as the water slows down.

Here are some things that work

1) seaweed is really good for catching sand, but it smells

2) not having offshore submarine channels that trap sand that gets swept out from a hurricane

3) keeping healthy dunes with active vegetation.

4) fiber mats

5) artificial breakwaters

Re: Erosion experience question

Posted: Sat Jul 05, 2014 8:40 am
by longwhitecloud
if there were dunes full of dune grass before - put them back. Sand just disappears sand stuck between massses of fine roots stays put waaay more

rock groins suck

Re: Erosion experience question

Posted: Sat Jul 05, 2014 11:41 am
by jimovo
The school my kids go to has an annual dune planting program that has been in place for 16 years. Every year we go down to our local beach access way and plant 500 dune plants along the edges of the dune within approx 500 yards either side. Four years ago a marker posts were placed to help measure dune movement. About two weeks ago we conducted this years planting. Relative to four years earlier, the dune where we have been planting has gained 8m horizontally and 1.8m vertically.

Re: Erosion experience question

Posted: Sat Jul 05, 2014 12:30 pm
by flyingweasel
.

Re: Erosion experience question

Posted: Sat Jul 05, 2014 5:24 pm
by loco4viento
Thanks everyone.