N-Viro Environmentally Friendly Marine Anchors

Environmental – N-Viro anchors leave little impact on the seabed, they are installed below the seabed, they are not dragged into position, ploughing the seabed in the process or creating an anchor block obstacle on the seabed. With  N-Viro anchors, seabed disturbance is minimal, in parts of NZ, where sea grass and other species of fragile flora occur, N-Viro anchors are the only system recommended by authorities. When N-Viro screw anchors are used in conjunction with an elastic mooring line material, chain/gravity moorings can be eliminated, thus reducing seabed disturbance even more.

Efficiency – N-Viro anchors consist of two main parts, the shaft and the anchor plate, both of which can be adapted to suit the prevailing sea bed conditions.  Once the anchor plate, weighing less than 100kgs has been installed, it is able to withstand a tension capacity (pull-out force) up to several hundred times its own weight.  The anchors work on uneven seabed terrain where others fail; both concrete block and drag-type anchors can be totally ineffective where significant changes in seabed inclination occur. Guaranteed anchor installation is logged via a Trimble GNSS system and on completion, certification is produced for the client, showing location, water depth, installed depth below seabed and hydraulic pressure (torque) required to install it. A further benefit of the superior tension/pull-out capacity of N-Viro anchors is that scope angles can be reduced; a warp ratio of 1.5:1 is commonly used, allowing more efficient use of space within lease boundaries.

Durability – N-Viro anchors are designed with a life expectancy in excess of 25 years; anchors are buried in the seabed, where they are protected from corrosion and deterioration.

Accuracy – MoorTech installs the screw anchors using a Trimble GNSS system, which also logs and stores information for client records and future reference. This tracking system gives high accuracy – sub-metre accuracy even at 60 metres depth can be achieved.

Safety – The MoorTech/N-Viro anchoring system is a remote (diverless) system.  Anchors are designed with a Safety Factor incorporated, with the unique installation and tracking system, the design loads are not only achieved, but also verified.

Reliability and cost-savings – Taking into consideration the accuracy of placement, certification of anchor capacity and other monitoring options available with this system, (the reliability of N-Viro anchors) means that neither the anchors nor structures held by them will move off the intended location. For the aquaculture industry, this translates into an increase in safety as well as a significant reduction in ongoing maintenance requirements.