A-JACKS

A-Jacks are high stability concrete armor units that are used in river, lake, and coastal applications to control erosion, stabilize shorelines, and provide habitat... Applications in rivers include the protection of river banks, toes, bridge piers, overflow structures, and drop structures. In lakes, bays, and other sheltered water settings, A-Jacks are often used to control erosion associated with small waves. In both river and lake applications they are also used to provide habitat and may be combined with bio-stabilization methods. In river and lake applications, the size of the A-Jacks tend to be small, typically 0.6 meters (2 feet) in length with a weight of 35-40 kg (77-88 lb). These units are small enough that they may be produced in a conventional block machine and may be hand placed.