Has anyone used a screwpile based mooring system? what diameter steel was used? how long do they last? what rode was used between the pile and surface buoy?

I like the idea of being able to not damage seagrass - but wonder about longevity compared to a big steel weight and hefty chain.

Can anyone recommend an installer?

If you think about it, a screw in mooring can only be effective if it is screwed into a solid base such as clay or maybe coral.

It is virtually impossible to screw into rock and ineffective if screwed into mud or sand.

A friend years ago who had the only private mooring at Green Island off Cairns was required by Marine parks to have an (environmentally friendly) screw in mooring. He complied and it was put in by Marine Parks. He kept his block mooring but put the weight of his 35 foot yacht on the screw in mooring with a secondary tackle on his old block.

The first blow bent and buggered the screw in mooring and his block mooring saved him from losing his boat. He rang Marine Parks and said come and have a look at your screw in mooring. They did and left him alone after that.

If you want an environmentally yet secure mooring, I suggest you stay with a block type mooring weight but change your tackle to all rope. That way you do not have chain dragging a circle of destruction around your block.

Read this thread:- www.seabreeze.com.au/forums/Sailing/General/Advice-please-best-solution-for-a-mooring-chain/