The most critical variable in potential failure of an ACB system is block protrusion (when one block sticks up relative to another in the direction of flow). Enviroflex® eliminates block protrusion with a vertically overlapping edge that locks the blocks together. Enviroflex® is also tapered at the block interface and holes to eliminate any sharp edges.  Most other horizontally interlocking blocks, especially when installed in large mats, have significant gaps between blocks that result in no interlock and the blocks are free to move up and down relative to each other. Even a tightly spaced horizontally interlocking block has the ability to move up and down relative to other blocks.

In most markets, ACBs are competitive in cost to 12" diameter (or greater) rock (or riprap) placed in an 18" or greater blanket thickness.   In most markets, ACBs are competitive with gabion mattresses and ACBs are typically more cost effective than cast in place concrete.

If the ACB system does not start and end at an existing structure, typically the blocks (and underlying geotextile filter fabric) are tucked into an anchor trench and backfilled and compacted with the appropriate material. In some cases, the "appropriate material" may be: concrete grout, stone, or grouted riprap instead or soil. Trench depth is typically 1.5 times the potential depth of scour. If the ACB system starts or ends at an existing structure, a reinforced steel grouted interface treatment is typically used to secure the blocks and insure that hydraulic undermining will not occur.