For the past 18 years, the Smith-Midland Corporation has been testing "Beach PrismsTM" at more than 20 sites on the Chesapeake Bay and its tributary rivers to help stop or reverse erosion. Beach Prisms are permeable, precast concrete products that work by reducing the amount of energy in incoming waves before they reach the shore. The waves pass through slots in the triangular three to four-foot-tall, 10-foot-long devices.

"Our experience has proven that Beach Prisms either slow the rate of shore erosion, stop erosion or reverse erosion by replenishing sand in front of and behind the Prisms," said Ashley Smith, vice president for sales and marketing for Smith-Midland.

The success of the devices depends on a few factors: the prevailing wind in relation to the shoreline, the tides, the fetch and the availability of sand in the surf.

According to an engineering study done by Land Engineering Inc., of Centreville, Md. Conducted at the Terrapin Nature Area on the east shores of the Chesapeake Bay, devices installed in the area made it through Hurricane Isabel with only minor dislocation.

Prisms are ideal for river and bay-front property owners who want an alternative to traditional armor stone, or groins and jetties.